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[Display omitted] • Free ammonia from hydrolysis of chicken manure promoted the hydrogenic fermentation. • Increased organic loading rate resulted in an increase of the hydrogen production. • Romboutsia (19.7 %) and Clostridium (16.6 %) were the dominant strains. • Biochar derived from solid digestate fraction was rich in calcium and phosphorus. • Bioaugmentation of liquid digestate removed 83.3 % of NH 4 -N and 66.2 % of COD. This study provides a sustainable approach to produce biohydrogen through the long-term hydrogenic fermentation of chicken manure (CM) in a semi-continuous stirred tank reactor (CSTR) under different organic loading rates (OLRs). To ensure the zero-waste route and sustainability , the total digestate was mechanically separated into liquid and solid fractions. The solid digestate fraction was thermally treated to produce biochar, while the liquid digestate fraction was biologically treated through bioaugmentation with a novel heterotrophic nitrification-aerobic denitrification (HD-AN (bacterial strain (Alcaligenes sp. ME-1). The results showed that the high concentration of free ammonia nitrogen (FAN) contents of CM could inhibit methanogenesis and induce hydrogen production. The ORLs of 2.5, 3.5, 4.5, and 5.5 gVS/L.d imposed to the CSTR resulted in volumetric hydrogen production (VHP) of 643.3 ± 37, 908.8 ± 64.5, 1077.8 ± 95.17, and 1383.3 ± 156.8 mL/L.d, respectively. The microbial community structures indicated the long-term adaptation of hydrogen-producing bacteria and methanogenesis inhibition. The bioaugmentation process removed 83.3 % of total ammonia and 66.2 % of the chemical oxygen demand (COD) from the liquid digestate fraction. The characteristics of the biochar derived solid digestate is suitable for land applications as fertilizer. The hybrid approach combining biohydrogenation, pyrolysis, and bioaugmentation, maximizes the utilization of chicken manure slurry while conforming to the sustainable development goals. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnCl 2 -SPI biochar was used to activate persulfate for ACP removal. • The generation and contribution of ROS depend on the persulfate-to-ACP ratio. • Electron transfer from ACP to persulfate was predominant at a low ratio. • ACP transformed to polymer via a coupling effect. This study investigated the effect of acetaminophen (ACP) removal through the ZnCl 2 -SPI/persulfate process and evaluated the production of reactive oxygen species (ROS) based on ACP concentration. ACP removal efficiency reached 96 % within 5 min, regardless of the initial concentration (40 μM and 200 μM). The change in pH had a minimal effect on the removal efficiency, and the reactivity improvement increased the removal rate at pH 4 and 10. The persulfate-to-ACP ratio significantly influenced ACP removal, with the minimum ratio required for effective ACP removal being 5. The scavenger test results showed that the effect of O 2 •− radicals prevailed when ACP concentration was 40 μM, whereas the effect of 1O 2 prevailed when ACP concentration was 200 μM. This indicates that ROS contribution depends on the persulfate-to-ACP ratio. When this ratio was high, ZnCl 2 -SPI and persulfate reacted to generate O 2 •− radicals via the radical pathway. Conversely, when this ratio was low, ACP and persulfate reacted to generate 1O 2 via the nonradical pathway. The difference in these mechanisms was analyzed through electrochemical analysis, confirming that ACP and persulfate reacted via a coupling effect. In conclusion, the ROS generated in the ZnCl 2 -SPI/persulfate process varied depending on the persulfate-to-ACP ratio, and the ROS generation path can be selectively controlled by adjusting this ratio. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low lignin content in algae makes thermochemical conversion to chars cost-effective. • Slow pyrolysis and HTC are preferred methods for algal char production. • Higher porosity and more diverse functional groups boost algal sorbent properties. • Enriched ash content in algal chars leads to higher cation exchange properties. • Modification of algal char enhances biosorbent properties. Biochar and hydrochar are carbon-rich solid products of algal and terrestrial biomass obtained through various thermochemical processes, mainly hydrothermal liquefaction, pyrolysis, and hydrothermal carbonization. Both are regarded as economical, potent, and environmentally friendly adsorbents for wastewater remediation. The versatile applicability of biochar and hydrochar, which is due to their enhanced surface physicochemical properties, includes efficient metal biosorption, soil fertility enhancement, and carbon sequestration. Consequently, there has been an increase in research for producing and exploiting biochar and hydrochar from algae. Both micro- and macro-algal biomass have strong potential due to their sustainability footprint and distinct properties. This review focuses on a comprehensive account of the synthesis of algal biochar and hydrochar and use in wastewater treatment to develop innovative solutions for efficient mitigation of several aqueous pollutants and heavy metal ions. The review discusses the various thermochemical production routes, biophysical characterization techniques, and modes of mechanism for wastewater bioremediation. Algal-based biochar and hydrochar are reported to have higher porosity and more diverse functional groups such as amines, hydroxyl, and carboxyl compared to their cellulosic and waste-derived counterparts, demonstrating an increased wastewater remediation efficiency. In addition, presence of inorganic metal including sodium, potassium, magnesium, and phosphorus in algal chars facilitates the formation of mesopores and graphite structures, improving their cation exchange capacity. Moreover, algal chars may exhibit pH buffering capacity, which could help stabilize the pH during wastewater treatment processes. Notably, the low O/C content of algal hydrochars enhances the binding and removal of organic pollutants including toxic dyes and antibiotics. The review highlights the development of modified algal chars to enhance the porosity, surface area, structural integrity, and adsorption capacity enabling a higher bioremediation potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • CWs filled with combined organic media were developed for effective AMD treatment. • Abiotic and biotic treatment performances declined with decreasing pH. • High acidity (pH 2.0) caused failure of multiple pathways for AMD treatment. • Growth of functional microbes for AMD bioremediation was inhibited at low pH. • SRB and organic degrading bacteria were keystone taxa for AMD treatment. The impact of influent pH value (2.0–5.0) on remediation performance of constructed wetlands (CWs) packed with composite organic solids consisting of walnut shells, biochar and plastic filters for acid mine drainage (AMD) was evaluated in this study. Reed straw broth was supplemented to drive the microbial remediation process. Influent pH had a notable impact on both abiotic and biotic remediation performance, with very low efficacy at pH 2.0 and the best performance achieved at pH 5.0. The adsorption capacity of CW substrates for heavy metals and the growth of functional microbes for AMD treatment were restrained at high acidity. Moreover, the removal of conventional pollutants, plant growth and metal deposition in the CWs were negatively impacted by the dosing of AMD with low pH. A low pH of 2.0 resulted in a distinctive microbial community in the CWs with almost no sulfate-reducing bacteria (SRB). In other CW systems, SRB (Desulfosporosinus and Desulfobulbus) and organic degrading bacteria (Cellulomonas and Geobacter) were identified as keystone taxa to carry out AMD bioremediation synergistically in phase Ⅱ. CWs filled with composite organic substrates are promising systems for AMD treatment, but the pH of AMD should be preneutralized to ≥ 3. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-rich pyrolysis effectively converts biomass into value-added products. • Theoretical computational modeling confirms the biomass three-component interactions. • Quantifying bio-oil component conversion to nitrogen-containing compounds (NCCs). • Unveils NCCs generation paths via intermediate chemical structures evolution analysis. • Machine learning is proven to be effective in handling interacting component systems. To optimize the targeted production efficiency of high-value nitrogen-containing compounds (NCCs: pyrrole, pyridine, nitriles, amides), this study extensively analyzed the interactions among cellulose, hemicellulose, and lignin under K and Ca presence during nitrogen-rich pyrolysis. By establishing a theoretical model, it confirmed how the three components interact during the pyrolysis process. The highest yield of biochar was observed with Ca. The proportion of NCCs in bio-oil increased by 4.45% with the addition of Ca and decreased by 1.81% with K. GC–MS characterization compared the evolution of intermediate chemical structures during the reaction with the formation of final products, specifically tracing NCCs generation pathways in bio-oil. First-time definition of bio-oil component conversion rates during nitrogen-rich pyrolysis. Aldehydes, ketones (with minimum conversion rates of 92.62% and 71.37%, respectively), and furans were identified as the most easily converted components into NCCs. Correlation analysis of bio-oil components supported this finding. Possible reaction pathways for NCCs generation during nitrogen-rich pyrolysis of ternary mixtures under mixed Ca or K addition conditions were identified. Additionally, the introduced machine learning model exhibited a high R2 value of 0.95 in predicting the product yields of ternary mixtures nitrogen-rich pyrolysis. This validates its effectiveness in handling interacting component systems. These results reveal interaction mechanisms among biomass three components in nitrogen-rich pyrolysis under K and Ca presence, offering new insights for optimizing NCCs production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Antibiotics and antibiotic resistance genes (ARGs) are ubiquitous in the aquatic environment. • BC-catalyzed peroxides demonstrate high efficacy in the removal of antibiotics and ARGs. • BC-based catalytic removal mechanisms are systematically summarized. • The challenges of BC-catalyzed peroxides technology facing currently are discussed. • Future recommendations are suggested for scaling-up the use of BC-based catalyst. The increasing contamination of water bodies with antibiotics, along with the emergence of antibiotic resistance genes (ARGs), poses a significant threat to both ecological systems and human well-being. Hence, the adoption of advanced materials for water treatment has become imperative. Biochar (BC), a carbon-rich material derived from biomass, possesses a large surface area, porosity, and functional groups. These attributes render it a promising candidate for use as a catalyst or catalytic support in the elimination of these emerging pollutants. This review explores the capacity of waste biomass-derived BC in catalyzing peroxides for the removal of antibiotics and ARGs. It includes a meticulous analysis of various biomass sources suitable for BC production, examines the influence of pyrolysis conditions on BC's properties, summarizes the removal efficacy of BC-activated peroxides on antibiotics and ARGs, and reviews different modification techniques that improve its catalytic performance. Furthermore, the review delves into the underlying mechanisms that facilitate the catalytic removal of antibiotics and ARGs. Moreover, this review seeks to connect experimental research with industrial implementation by pinpointing the key challenges that need to be addressed. It examines the advantages of using BC for this purpose, in addition to addressing its limitations, such as potential secondary pollution from BC-based catalysts. The applicability of BC-based catalysts in real-world water treatment systems, as well as their economic viability, is also discussed. Finally, the review proposes future research directions to foster the development of sustainable BC-based catalytic technologies for water treatment. By addressing these key issues, this review offers valuable insights for translating the potential of BC into practical and effective use for treating antibiotic/ARG-contaminated water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pyrolysis and activation in a dual fluidized bed was successfully operated. • Physical and chemical activation by flue gas and H 3 PO 4 occur simultaneously. • Maximum biochar yield and iodine number were 42.3 wt% and 648.5 mg/g, respectively. • Pyrolysis and activation of one-step method is superior to two-step method in DFB. • H 3 PO 4 favors formation of pores and surface functional groups with rising ratios. Interconnected pyrolysis and activation is a novel technology for combustible gas and biochar production in dual fluidized bed (DFB). The study proposed one-step and two-step methods for pyrolysis and activation of biomass in a pilot scale DFB with capacity of 100 kg/h. Physical and chemical activation occurred simultaneously in DFB system by phosphoric acid (H 3 PO 4) impregnation pretreatment of pear wood chips, and flowing hot flue gas and steam. Stable operating parameters were observed for both methods. The one-step method was superior to the two-step method in terms of the pyrolysis gas quality, biochar pore distribution, micro- and meso-pores structures of biochar, while one-step method reduced the biochar yields. As an activation agent, H 3 PO 4 increased the yields of biochar and pyrolysis gas, promoted formation of micropores and enriched the surface functional groups of biochar with increasing ratio of H 3 PO 4. H 3 PO 4 to biomass ratio of 1:5 reached the maximum biochar yield of 42.3 wt% and highest iodine adsorption value of 648.5 mg/g, increasing by 70.6 % and 90.3 % compared to the biochar without H 3 PO 4 pretreatment, respectively. This DFB system facilitated the diversified use of fluidized beds and the co-production of biochar and product gas with energy saving and CO 2 emission reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • BC/FBC made from agricultural waste were pre-deposited in GDM systems. • BC pre-deposition improved biofouling layer heterogeneity thus higher stable flux. • Presence of biochar significantly enhanced microbial activity and pollutant removal. • The presence of Fe in FBC inhibits microbial activity of the biofouling layer. The relatively unstable dissolved organic removal efficiency and low water flux during long-term filtration of gravity-driven membrane (GDM) are major barriers to its widespread application in decentralized water treatment. In this study, the role of pre-deposited biochar (BC) and iron-modified biochar (FBC) layers in GDM for treating surface water were firstly investigated, aiming to explore the feasibility of cost-effective agricultural waste as pre-deposition materials. Compared to the relatively low removal efficiency of GDM control group (DOC 18.1 %, UV 254 10.6 %), both BC pre-deposited GDM (BC-GDM: DOC 36.0 %, UV 254 39.9 %) and FBC pre-deposited GDM (FBC-GDM: DOC 31.9 %, UV 254 32.4 %) show considerably enhanced removal efficacy. Also, pre-deposited BC/FBC layers accelerated the start-up process for NH 4 +-N removal. The enhancement of functional bacteria such as Proteobacteria and Nitrospirota was accountable for pollutant removal efficacy. Regarding the flux stabilization, compared to the GDM control system, the final stable flux of BC-GDM increased by 3.61 % while FBC-GDM decreased by 9.55 %. The presence of BC layer increased the bacterial activity, porosity of the formed biofouling layer, thus favored the flux enhancement, resulting in a lower water production cost. Conversely, the presence of Fe in FBC may inhibit the microbial activity and diminish its pore structure, leading to reduced flux transport. Our study suggests simple pre-deposition of BC shows positive effect on ultra-low pressure GDM filtration, highlighting the potential application of low-cost agriculture waste in decentralized drinking water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The two-step KOH activation led to ultra-high microporous ratio and surface area biochar. • The structure–activity relationship and mechanism of CO 2 capture by biochar were studied. • The CO 2 uptake is:24.77 mmol/g (25 °C/30 bar)、3.46 (25 °C/1 bar) and 5.42 mmol/g (0 °C/1 bar) • The activation mechanism of KOH on biochar was analyzed. • Outstanding adsorption selectivity of CO 2 /N 2 (123 at 0.02 bar) for 4–9-2-m. Porous carbon-based CO 2 capture holds great promise. However, the preparation process, pore structure and oxygen/nitrogen functional groups of porous carbon on CO 2 adsorption still remain unclear. Herein, we develope straw-based biochar with ultra-high specific surface area(SSA), high micropore ratio and different O/N content by modifying the two-step KOH activation procedure and confirm the KOH activation mechanism, CO 2 adsorption characteristics, and the structure-effect relationship of CO 2 capture. The KOH activation process is controlled by the activation temperature and is divided into five temperature zones. The pickling treatment enhanced the activation effect of biochar, with a SSA of 3567.33 m2/g and a microporous ratio of 96.05 %. The potassium-containing active components reacts with the defective carbon structure above 800 °C catalyzed by alkali and alkaline earth metals(AAEMs), but reacts with the aliphatic hydrocarbon group after pickling. H-4–9-4-m has a maximum CO 2 adsorption capacity of 24.77 mmol/g (25 °C/30 bar), whereas 4–9-2-m has a maximum capacity of 3.46 (25 °C/1 bar) and 5.42 mmol/g (0 °C/1 bar) and outstanding CO 2 /N 2 selectivity (123 at 0.02 bar). The pressurized CO 2 adsorption capacity is positively correlated with total pore volume. While under atmospheric pressure, the optimal adsorption site of biochar at 25 °C is ultramicroporous(0.5 nm) and oxygen-containing functional groups, and transforms into ultramicroporous(0.7 nm) and N-5 groups at 0 °C. The simulation results show that 0.5 nm is the pore size of CO 2 adsorption from monolayer to bilayer, and both oxygen/nitrogen-containing groups could increase the CO 2 adsorption capacity of biochar. This study provides guidance for the preparation of excellent carbon-based CO 2 adsorbents according to application scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sulphuric acid recovers phosphorus from wastewater-microalgae derived biochar. • Metals like Fe, Ca, and Mg are remained in the biochar materials. • Metal-containing and S-doped biochars show strong electrochemical performance. • Acid leaching for biochar can provide carbon-negative energy storage solution. This study proposes a strategy for phosphorus recovery from algae biomass while simultaneously enhancing the electrochemical capacitance of resulting biochar in supercapacitor applications. Use of sulphuric acid leaching process on both wastewater microalgae and seaweed biochar demonstrated high phosphorus recovery rates, ranging from 93.4% to 95.4%, while at the same time retaining 52.7% to 58.6% of Fe content in the biochars. By modifying the sequential order of leaching (L) and physical activation (A) as LA and AL, the strategy allows for the optimisation of phosphorus recovery and the electrochemical properties of activated biochars. During the LA process, a more porous structure formed and more S-containing functional groups occurred compared to AL which explained the higher specific capacitance (486.3F g−1 at a current density of 1 A g−1) of wastewater microalgae biocarbon with the LA process. Consequently, the life cycle assessment of this strategy revealed a significant global warming reduction potential of 1.34–2.94 tonnes of CO 2 -eq/yr for each tonne of biochar produced. This indicates that sulphuric acid-assisted biochar production could be a sustainable strategy for waste management and carbon sequestration, while simultaneously generating economic profits from valorised carbon material for energy storage applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn/Al, Co/Al, Mg/Al and Ca/Al − combination of metals at the molar ratio 3/1 in hydrotalcite. • pH 6, time 360 min., temperature 333 K allowed to obtain the highest q t values. • The best match to Elovich and Temkin models suggesting chemisorption. • Ca/Al-LDH@BC the best cerium removal compared with other composites. • Process involves complexation, ion exchange, precipitation and electrostatic interactions. The innovative LDH@BC composites containing combination of metals: Zn/Al, Co/Al, Mg/Al, Ca/Al at the molar ratio 3/1 were synthesized using the co-precipitation method at constant pH. The composites were applied to remove Ce(III) ions from aqueous solutions. Batch experiments were conducted for determination of influence of solution pH, phase contact time, solution concentration and temperature. The kinetic and isotherm parameters were found using the non-linear regression method. As follows from the thermodynamic tests LDH@BC are more effective removal of Ce(III) ions at higher temperature and the sorption process is unforced and spontaneous. The leaching studies proved that 1 mol/L nitric acid is the best desorbing agent for Ce(III) ions deposited on the sorbent surface. Additionally, the composites were investigated applying the XRD and BET analyses (before sorption) as well as the ATR-FTIR, SEM-EDX, XPS methods (before and after the Ce(III) ions sorption). In summary, the introduction of hydrotalcite composed of Zn/Al, Co/Al, Mg/Al, Ca/Al as modifiers of biochar surface produced a potentially more cost-effective, and non-toxic cerium adsorbent for waters and wastewaters treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel mono- (La) and bi-metal (CeLa) biochars were synthesised from conifer brash. • High adsorption capacities were detected (78 mg/g) in eutrophic lake water. • The governing adsorption mechanism was through ligand exchange. • La carbonate was the major ligand for exchange with phosphate on the surface. • Low toxicity response with marginal inhibition (<5%) was noted with Lepidium sativum. Phosphorus as a diminishing finite resource, yet is an essential element for the growth of biota. However, elevated concentrations in water can imbalance ecosystems and cause eutrophication. To address both problems, two highly efficient biochars, namely La-OB and CeLa-OB were synthesised by lanthanum and cerium doping. The performance of La-OB and CeLa-OB were evaluated in both batch and dynamic regimes with synthetic phosphate (PO 4 3--P) solutions and eutrophic lake water. PO 4 3--P adsorption mechanisms were investigated in terms of pH, kinetics, isotherms, activation energy, thermodynamics and using in-depth characterisation (XPS, FTIR, XRD, BET, pH pzc and SEM-EDX). The feasibility of using such biochar in 'real life' situations was studied with column filtration of lake water with low and high PO 4 3--P concentrations. Reusability/desorption and toxicity in the water environment was also considered. The mechanistic study showed that both biochars predominantly had inner-sphere complexes with La and Ce ligands (as a monolayer), while outer-sphere complexation was less common. The exothermic adsorption process followed the Elovich kinetic and Langmuir isotherm models, with a maximum adsorption capacity of 112 mg/g for La-OB and 40 mg/g for CeLa-OB. In column filtration trials the adsorption capacity reached 78 mg/g, while low metal leaching (0.08 mg/L) and low toxicity to Lepidium sativum germination were detected. The results indicated that these biochars, especially La-OB, could be used in circular economy-based water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Organic solid waste-supported nanomaterial was applied to mediate toxic chemicals looping in rice. • Nanoscale Fe-(oxyhydr)oxide and LDH components from FLBC determined As and Cd fate. • FLBC application promoted the amorphous conversion of Fe-oxides on Fe plaques. • Nano-LDH bioassembly was firstly reported to influence As and Cd species in root. • FLBC amendment preferentially accumulated DMA and Cd in rice due to LDH introduction. The impact of organic solid waste-supported nanomaterial application on the biogeochemical looping of arsenic (As) and cadmium (Cd) in rhizosphere-root system of rice remains unclear. This study investigated the biochar-supported Fe-(oxyhydr)oxide and layered double hydroxide (FLBC) to modify As and Cd species and their accumulation in rice rhizosphere system under all life-cycle. The results demonstrated that total As and Cd in porewater and rice tissues decreased by > 70 % following 1 wt% FLBC application, close to national standards in grain. Inorganic As levels significantly decreased in roots and grains under FLBC application, resulting in the preferential accumulation of organic As like dimethylarsenate. FLBC amendment substantially increased the Fe plaques on root surfaces due to a rise in Fe(II) sink influenced by Fe(III)-reducing bacteria, and then promoted the conversion of crystalline-like FeO x to an amorphous-like structure on Fe plaque through X-ray diffraction and transmission electron microscope technologies (TEM), eventually reducing the As and Cd availabilities. The ultrastructural characterization, employing TEM equipped EDS spectrometer, revealed the bioassembly of nanoscale layered double hydroxide for the first time within the vacuoles of xylem cells in the root apex under FLBC amendment. This process allowed the transformation of As and Cd species from metastable Fe–Al oxides-bound compounds to stable complexations of cysteine-bound As(V)/Cd and Cd(OH) 2 within the intracellular spaces, as demonstrated by X-ray absorption near fine structure spectrum. In short, FLBC hindered the transformation and accumulation of As and Cd species in the rhizosphere-root system, providing a fresh perspective on organic solid waste-supported nanomaterials for ensuring safe crop production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced hydrophobicity of Janus structured photothermal conversion materials via impregnating silane solution. • Utilization of agricultural and forestry waste significantly promotes the sustainability of Janus materials. • Innovative portable air water intake device that can obtain water from the atmosphere. • A portable air water intake device produces clean water with 1.74 L m−2 day−1 fulfill an individual requirement. The utilization of photothermal conversion materials to enhance the desorption performance of hygroscopic salt solutions through interfacial photothermal effects presents a promising approach for the continuous extraction of water from the atmosphere. To improve the desorption efficiency of hygroscopic salt solutions, the objective of this research is to employ agricultural and forestry residues, such as corn straw, in conjunction with polyurethane sponges, for the production of an innovative Janus structure carbonized biomass photothermal conversion material. Compared to single-layer structured photothermal conversion materials, the pure water evaporation rate increased from 2.42 kg m-2 h-1 to 3.20 kg m-2 h-1 when utilizing the Janus structured photothermal conversion material. Remarkably, this material demonstrates outstanding resistance to salt, allowing it to endure 8 h evaporation cycles with 30 wt% NaCl without salt crystallization. Therefore, it is well-suited for the continuous desorption of liquid hygroscopic agents. Moreover, the portable air–water extraction device, which incorporates Janus structural photothermal conversion material to enhance the performance of 30 % LiCl, has been shown to effectively extract water in practical settings. It achieves a water intake rate of 1.74 L m-2 d-1 at 50 % humidity. This approach is distinguished by its simplicity, cost-effectiveness, and efficient utilization of solar energy resources, providing a promising solution to mitigate the shortage of fresh water resources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar modified with polysaccharide has more functional groups and active structures. • Different polysaccharide modifications produce different effects on biochar. • Remediation of pollutants in the environment through multiple mechanisms. • Polysaccharide-modified biochar has promising applications in real-world environments. • Polysaccharide-modified biochar meets the concept of green chemistry. With the rapid development of industry and agriculture, global environmental problems are becoming more and more serious. It is urgent for us to find green solutions to improve the environment. Biochar is a potentially cost-effective carbonaceous resource with a wide range of applications in agriculture and the environment. Modification of pristine biochar can further improve its performance in the target application. Polysaccharides-modified biochar are receiving increasing attention as a promising material for environmental treatment because they can combine the advantages of polysaccharides and biochar. In this paper, the differences and preparation methods of different polysaccharide-modified biochar, as well as the effects and mechanisms of polysaccharide-modified biochar in removing organic and inorganic pollutants from the environment were systematically discussed for the first time by critically analyzing the existing studies. In addition, the recycling capacity and methods of this type of modified biochar, and the current applications and effects in the real environment were also fully summarized and discussed. The future development of polysaccharide-modified biochar should focus on its recycling methods and costs as well as more in-depth exploration of its application in real environments. It is believed that this material can achieve good results in the field of environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biogas yield of cattle manure and green algae was 176 mL/g VS. • RSM and ANN models have been used to study the anaerobic digestion of biochar dose. • Effects of ozonation and ultrasonic pretreatment on culture have been studied. • After adding 150 mg BC to the environment, the biogas yield was 717 mL/g VS. • According to performance indicators, ANN performed relatively better than RSM. This study aimed to optimise and model biogas yields using artificial neural networks (ANN) and response surface method (RSM) of biogas yields after adding different doses of ozonation and ultrasonic pretreated biochar (BC) doses to the co-digestion of cattle manure and green algae substrates, with and without S.Parkle culture in the environment. The results of the RSM-D optimal design indicated that, in the absence of S.Parkle culture in the environment, the optimum ultrasonic pretreated biochar (UPBC) doses were 29.23 mg (for 100 mL digestion volume) and the corresponding optimum biogas yield was 340.50 mL/g volatile solids (VS). In the case of S.Parkle culture in the environment, the optimum ozonation pretreated biochar (OPBC) dose was 55.96 mg and the corresponding optimum biogas yield was 660.40 mL/g VS. ANN and RSM model performances were analyzed using different statistical indicators and ANN result obtain showed absolute percentage error (MAPE) value of 2.1, mean average error (MAE) value of 0.347, standard error of prediction (SEP) value of 0.590, and root-mean-square error (RMSE) value of 0.55, mean squared error (MSE) value of 0.31, the sum of the squared estimate of errors (SSE) value of 4.9 and coefficient of determination (R2) value of 0.9999, and RSM result reveals MAPE of 0.0030, MAE value of 30.693, SEP value of 45.57, RMSE of 42.63, MSE value of 1817.6, SSE value of 29,081 and R2 of 0.9612. The model performance indicators and estimation results indicate that the ANN performs relatively better than the RSM in modelling the process. It is recommended that the optimum OPBC and UPBC doses be tested and verified on different substrates. [ABSTRACT FROM AUTHOR]

[Display omitted] • The sources, preparation, modification, and environmental remediation applications of biochar have been discussed in detail. • The application of biochar activated persulfate for pollutant removal in water and soil has been extensively discussed. • The mechanism of biochar activation of persulfate has been extensively discussed. • DFT calculations are used to explain the mechanism of action of biochar and the microscopic activities of catalytic adsorption processes. Soil and water environmental pollution continues to pose a substantial threat, accounting for approximately 30 % of all global environmental issues. Among the various remediation strategies, biochar, characterized by its exceptional porous structure, a specific surface area ranging from 500 to 1500 m2/g, and a diverse array of functional groups, stands as a highly effective adsorbent and catalytic material. It has been extensively applied in environmental restoration efforts. Notably, in recent years, the technology involving biochar-activated persulfate (PS) has garnered significant attention, accounting for over 20 % of all published research in this field. A detailed discussion was conducted on the preparation methods of biochar, the research progress and mechanism of activating PS to remediate organic pollutants in soil and water by summarizing and refining relevant research. Specifically, the application of Density Functional Theory (DFT) calculations in elucidating the interaction mechanisms between biochar and PS has been thoroughly investigated, uncovering the electron transfer process between the functional groups on the biochar surface and PS, thus facilitating the degradation of organic pollutants. Moreover, this article also explores the challenges and future directions of the biochar-activated PS technology in practical applications, aiming to offer new insights and methods for the restoration of soil and water environments. It provides a theoretical foundation for further exploration of its mechanism of action and the optimization of application conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel nitrogen-doped biochar material loaded with S-nZVI was prepared. • Both adsorption and reduction acted on the removal of norfloxacin. • Norfloxacin was degraded by the direct electron transfer and H* pathways. • Nitrogen species and sulfur species were involved in the cycle of iron species. In this study, a nitrogen-doped biochar loaded with sulfidated nanoscale zero- valent iron (S-nZVI@NBC) was synthesized using reed as the precursor to efficiently remove norfloxacin (NOR) from water. S-nZVI@NBC could completely remove NOR within 180 min at a removal rate of 0.026 min−1, exceeding the performance of materials without sulfur or nitrogen species. Density functional theory calculation showed that S-nZVI@NBC had strong NOR adsorption performance (−2.075 eV) and better electron transfer capacity (0.449 e). The nitrogen and sulfur species in S-nZVI@NBC promote the degradation of NOR by H* (dominant, 97.4 %) and direct electron transfer (DET) (synergistic, 2.6 %) pathways. In addition, XPS analysis further showed that sulfur species promoted iron cycling with the assistance of nitrogen species in the reaction, making S-nZVI@NBC had better removal performance to pollutants and practical application potential. The removal efficiency of NOR could still be maintained at about 60 % after 6 cycles, which might benefit from the dual protection of nitrogen-doped carbon network and sulfur shell. Piperazine ring cleavage and defluorination were the main ways of the NOR degradation by S-nZVI@NBC, thus reducing the biotoxicity of NOR. This study clarified the reaction mechanism of S-nZVI and nitrogen species to promote the degradation of pollutants by heterogeneous materials, thereby providing a theoretical foundation for the synthesis and application of the integrated adsorption/degradation materials. [ABSTRACT FROM AUTHOR]

• Biochar derived from low-lignin biomass is highly susceptible to oxidation. • Aged low-lignin biochar releases significant DOM, decreasing soil As stability. • Oxygen-functional groups on aged biochar enhance Pb, Zn, and Cu stability. • Cu stability with biochar aging requires further research. Understanding biochar aging is a critical factor in predicting its long-term effects when added to soil. This study explores the complex links between lignin content in biochar feedstock and biochar stability during accelerated aging, including its influence on heavy metal mobility in soil. In this study, nine types of biochar based on fir (F), pine (P), and oak (O) sawdust were produced at 400 °C, and lignin was extracted from them using ammonia after 0, 3, and 7 days (named as 0FB, 3FB, 7FB, 0PB, 3PB, 7PB, 0OB, 3OB, and 7OB). Subsequently, each biochar was subjected to 25 cycles of wet-dry (WD) and freeze–thaw (FT) aging. The aged low-lignin biochars (7FB, 7 PB, and 7OB) released more dissolved organic matter (DOM) and contained more oxygen-containing surface groups on their surfaces than the high-lignin biochars (0FB, 0PB, and 0OB). The low-lignin biochars with high DOM leaching released 37–85 % more anionic arsenic (As) from biochar-amended soil after 25 cycles of aging than the high-lignin biochars. The stabilities of lead (Pb), zinc (Zn), and copper (Cu) were increased due to strong binding to surface functional groups on the low-lignin biochar. The acid-soluble fractions of Pb, Zn, and Cu were converted to organic-bound fractions as biochar aging progressed, with the degree of transformation being inversely proportional to the lignin content of biochar. This research highlights the crucial role of lignin in shaping biochar stability, and reveals how biochar stability impacts soil heavy metals speciation, opening new avenues for effective biochar-based environmental solutions and the promotion of soil health. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar-assisted AnMBR was established to treat ammonia-rich swine wastewater. • Adding biochar promoted CH 4 yield by 9.1–33.3 % under ammonia contents of 3–6 g/L. • Biochar enriched Syntrophomonas and Methanosarcina under ammonia stress. • Biochar-EPS-microbes matrix was potentially formed to enhance CH 4 production. • Biochar boosted EET-based methanogenesis under high ammonia stress. Anaerobic Membrane Bioreactor (AnMBR) is regarded as an advanced technology for the anaerobic digestion (AD) of swine wastewater. However, the high ammonia level in swine wastewater is a crucial issue to inhibit methane production. This study aimed to establish a biochar-assisted AnMBR (BC) to mitigate ammonia inhibition during AD of swine wastewater. As the gradual ammonia loading rate (ALR) increased from 3.0 g/L to 6.0 g/L, BC maintained methane yields ranging from 74.9 % to 48.1 %, which were 9.1 % to 33.3 % higher than those of a regular AnMBR (CT). Moreover, the COD removal efficiency steadily surpassed 80 %. Although the increase in ALR had negative effects on both BC and CT, the presence of biochar enhanced the methanogenic activity of bulk sludge, specifically accelerating processes involved in syntrophic acetate oxidation and CO 2 -reducing methanogenesis under high ALR conditions. Integrated characterizations using PARAFAC-based EPS analysis, INT-ETS, and WO 3 probe-based extracellular electron transfer (EET) activities indicated that biochar stimulated the secretion of humic-like and aromatic protein-like compounds in the TB-EPS, which likely established a redox-active matrix with biochar between VFA oxidation bacteria and CO 2 -reducing methanogens to facilitate EET. This potentially made the syntrophic VFA oxidation with favorably thermodynamic kinetics under high ammonia stress. Furthermore, the analysis of microbial community coupling prediction of functional genes associated with methanogenic pathways revealed that as ALR increased, the presence of biochar re-shaped the microbial communities by enriching electro-active Syntrophomonas and Methanosarcina / Methanospirillum , which mainly triggering EET-based syntrophic methanogenesis by accelerating the intracellular enzymatic transformation from Formylmethanofuran to 5,10-Methylenetetrahydromethanopterin process. We expect the major findings of this study provide new insights to understand the mechanisms of biochar alleviating ammonia inhibition during long-term operation of AnMBR. [ABSTRACT FROM AUTHOR]

[Display omitted] • B-SSBC is used to activate peroxymonosulfate and degrade tetracycline in urine. • HCO 3 −/CO 3 2− in urine contributes to the degradation of tetracycline. • DFT calculations reveal the mechanism of tetracycline degradation in urine. • The B-SSBC/PDS system removed up to 77.35 % of tetracycline in urine at pH = 7. In this work, we reveal the influencing factors and mechanisms of tetracycline removal by peroxydisulfate activated with boron-modified sewage sludge biochar in urine. Advanced characterization techniques showed that the introduced BCO 2 and BC 2 O were the main activation sites for peroxydisulfate, which maintained a high removal rate of tetracycline in synthetic and actual urine (86.48% and 77.35%). HCO 3 −/CO 3 2− and some organic matter in the urine contributed to the degradation of the tetracycline. Theoretical calculations showed that CO 3 2− in urine could be efficiently adsorbed by the introduced B atoms and converted to CO 3 ·− by peroxydisulfate to assist the degradation of tetracycline, which was attributed to the special electronic structure of the B atoms as well as the strong electron-enrichment ability of the neighboring O atoms. The potential toxicity of tetracycline and its degradation intermediates was further explored, revealing a significant reduction in toxicity during boron-modified sewage sludge biochar/ peroxydisulfate treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • s-ZVI-coupled Myriophyllum aquaticum- derived biochar favors C storage more than I.H. • Biochar nature or feedstock may control C trap and N removal gains from Fe-C coupling. • Biochars trigger C dynamics depending on trade-offs between priming and increased MBC. • Enhanced iron gate contributes to synergistic C sequestration and C sink augmentation. • β -glucosidase activity and Fe-OC increases jointly drive C cumulation in Fe-C ditches. Carbon dioxide (CO 2) is a more powerful greenhouse gas due to its enhanced instantaneous radiative forcing. Since agricultural ecological ditches (eco-ditches) controlling agricultural non-point source pollution are potential CO 2 hotspots, carbon capture technologies must be deployed immediately to sequester carbon and combat climate change. Zero-waste biochar, a negative-carbon technology, remains contentious regarding C sequestration. Iron (Fe) enhances long-term organic carbon (OC) preservation, but the cascading effects of Fe-biochar interactions on the promotion of C accumulation are unclear in eco-ditches. In this paper, we fill these research gaps and employ sponge iron (s-ZVI) and biochar coupling (Fe-C) to enhance the iron gate C protection in eco-ditches. The results reveal that Myriophyllum aquaticum(M.A.) -derived biochar prepared by low-temperature pyrolysis (Biochar_M.A.) enjoys the highest FI, the lowest SUVA254 and SUVA280 and moderate dissolution stability. The coupling of s-ZVI and environmentally compatible Biochar_M.A. achieve a triple benefit situation of C sequestration, C sink, and pollutant removal. Overall carbon gain is jointly determined by abiotic controls and biotic controls. The carbon burial effects of biochar-amended eco-ditches are mainly controlled by the trade-offs between Fe-bound OC mineralization via the biochar-induced prime effect and preservation of OC derived from microbial biomass. The unique Fe-C boosts the rusty sink and yields a negative priming as a result of the dominance of Fe-OC. The upregulated β -glucosidase activity and new-formed Fe-OC indirectly and directly contribute to overall C gain in Fe-C-filled eco-ditches, respectively. These findings provide novel insights into the coupled biotic-abiotic contribution mechanisms underlying the iron gate and reverse enzyme latch phenomenon and advance more robust and prospective theoretical knowledge of C dynamics that are not restricted to eco-ditches, soil, constructed wetlands C storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • KOH introduced carbonyl groups and urea had a deoxygenation effect for the treatment of biochar. • The BK-N-8 sample exhibited a high initial conversion rate and excellent durability. • The weaker interaction between hydrated cations endowed BK-N-8 with favorable durability in catalytic capacity. • Thermodynamics and kinetics calculations clearly elucidated the effects of surface functional groups. • Key roles of epoxy and pyridinic groups for the steady conversion of SO 2 were revealed. The catalytic oxidation of SO 2 (COS) by dissolved oxygen in aqueous solution allows to recycle sulfate salt/sulfuric acid from the SO 2 -containing flue gas, and high-performance catalysts are desired for an efficient COS process. In this study, the chestnut leaves-derived biochars treated by the co-pyrolysis process with KOH/urea exhibited a favorable capability to catalyze the oxidation of SO 2 in aqueous solution. The BK-N-8 biochar catalyst was the optimal one due to its moderate nitrogen content and appropriate surface functional groups. It exhibited a fast initial conversion rate from SO 2 to SO 4 2− (6.50 μmol g−1 s−1), and an excellent cycling durability for the COS process. The material showed a catalytic activity that surpassed all the reported carbonaceous materials. The surface functionalities were revealed to be the decisive factor for the conversion rate and durability of catalytic capacity. The superiority of the BK-N-8 with pyridinic N-doped aromatic cluster (AC) was further investigated via density-functional-theory calculations. The epoxy groups from O 2 dissociation at the edge sites of ACs played a pivotal role for COS process onto biochars. This study provides insightful information for an in-depth understanding of the mechanism of COS process catalyzed by carbonaceous materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mutual element doped FeS 2 /Biochar was synthesized by wet-mechanochemical method. • FeS 2 /Biochar showed superior Fenton catalytic performance with negligible Fe release. • Newly formed Fe-C site contributed to the H 2 O 2 adsorption and barrierless dissociation. • Functional group, Fe-C and C-S-C bonds by milling expedited Fe3+/Fe2+ redox-cycle. • Dominant radicals (•OH, •O 2 –, •SO 4 -) and auxiliary 1O 2 both existed. FeS 2 -biochar composites have been considered as promising heterogeneous Fenton materials for pollutants removal. However, the chemical synthesis of element-doped FeS 2 -biochar composite with superior performance and the comprehensive investigation for its underlying multiple synergistic mechanism remain a difficult endeavor. Herein, a novel FeS 2 /Biochar nanocomposite with mutual element doping was firstly synthesized by facile wet-mechanochemical method using iron, sulfur and bamboo-biochar for efficient organic pollutant (sulfamonomethoxine, SMM) removal. Experiment and DFT calculation results revealed that multiple synergistic effect between FeS 2 and biochar derived from newly formed Fe-C and C-S-C bonds induced the abundant reactive oxygen species (ROS) and excellent electron transfer capacity. Fe-C sites facilitated the H 2 O 2 adsorption and populated O-O bond in H 2 O 2 for its barrierless dissociation into •OH via forming bridging C-Fe-O-O-Fe bond. Oxygen vacancy, C-S-C and Fe-C bonds, persistent free radicals (PFRs) accelerated the generation and transformation of ROS, which resulted in dominating free radical (•OH, •O 2 – , •SO 4 -) and auxiliary non-radical (1O 2) pathway. Meanwhile, Fe3+/Fe2+ redox-cycle was expedited by electron donor/shuttle (S 2 2-, BC, •O 2 –, C-S-C and Fe-C bonds). All these specialties contributed to the superior performance of FeS 2 /Biochar Fenton system for SMM removal at wide pH range (3–11) with negligible Fe release. Completely SMM (50 mg/L) removal was achieved within 20 min for 8 successive reuses. This work emphasized the concept of building mutual element doping on molecular level in enhancing FeS 2 -Biochar synergy towards efficient environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • An integrated HTC–PY technique was implemented to valorizes CS and YW. • HTC improved carbon content, deoxygenation, and higher heating value. • CSH and YWH hydrochars' co–pyrolysis modeled via hybrid RSM–ANN. • The pyrolysis of blends reduced the average activation energy. • Pyrolysis of hydrochars enriched bio–oil with hydrocarbons and phenols. Hydrothermal carbonization (HTC) presents a promising method for converting carbonaceous waste into renewable fuels, facilitating energy recovery. This study focuses on the HTC pretreatment of microalgae (Chlorella sorokiniana) and yard waste, examining their physicochemical structural changes, component migration, and potential for valorization via integrated HTC and pyrolysis processes. HTC notably enhances the carbon content while reducing oxygen and nitrogen levels in these feedstocks, producing a clean solid fuel with high energy density. The study investigates the pyrolytic behavior of hydrochars and their blends using different analytical techniques, kinetic modeling, and fixed–bed reactor experiments. The blends with 90% and 70% of microalgae hydrochar (CSH) exhibited the most significant synergistic effects during co–pyrolysis, evident in its devolatilization behaviors and reduced activation energies. Integrating artificial neural networks and response surface methodology models facilitated optimization of pyrolysis parameters and accurate prediction of bio–oil, biochar, and gas yields. The analytical techniques enabled characterization of pyrolysis products, revealing notable changes in bio–oil and biochar compositions, suggesting potential enhancements. The study comprehensively evaluates the HTC–pyrolysis approach's potential for converting microalgae and lignocellulosic biomass into eco–friendly biofuels for industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A system containing Co-ZIF reinforced kraft lignin biochar catalyst was designed. • Co@NPC-KLB-A showed perfect catalytic activities for vanillin hydrodeoxygenation. • H-donner solvent was used for vanillin hydrodeoxygenation instead of external H 2. • Theoretical calculations further confirmed the active sites of the catalysts. • Co@NPC-KLB-A catalyst showed excellent stability after five recycling runs. Large amount of lignin was produced annually as a byproduct in papermaking and pulping processes, the challenges in disposal methods had posed serious obstacles for advanced carbon materials and value-added chemicals. This study involved the preparation of kraft lignin (KL) loaded metal–organic framework (ZIF-67) material derived Co nanoparticles carbon using various methods to produce kraft lignin biochar-based carbon materials (Co@NPC-KLB). The novel and advanced carbon materials was utilized for lignin derived bio-oil hydrodeoxygenation to generate high value fuels and chemicals. It could achieve nearly 100 % vanillin (VAN) conversion and 88.49 % 2-methoxy-4-methylphenol (MMP) without the extra hydrogen at 240 °C in ethanol. The results demonstrated that highly active and stable Co nanoparticles, large specific surface area, smaller nano Co nanoparticles, strong metal-support interaction and rich Lewis acid sites on the surface of biochar support exhibited a positive promoting effect on VAN hydrodeoxygenation to generate MMP. Furthermore, density functional theory (DFT) also confirmed that synergistic effect of Co nanoparticles and kraft lignin biochar promoted a high adsorption energy of VAN on the surface of kraft lignin biochar, enhanced the catalytic ability of the hydrodeoxygenation process. This study provided a novel approach for utilizing kraft lignin in preparation functional catalysts, opening up new opportunities for designing efficient biochar-based materials for advanced carbon materials and high-value chemicals. [ABSTRACT FROM AUTHOR]

[Display omitted] • BNMs exhibit unique properties that enable effective contaminant removal; • Diverse feedstocks and modification methods can enhance BNM performance; • BNMs remove heavy metals, nutrients, pharmaceuticals, dyes, and organics; • BNMs enhance crop resilience by improving soil quality and suppressing pathogens; • Interdisciplinary research is needed to optimize BNMs and ensure sustainable use. Transferring biochar nanomaterials (BNMs) from laboratory studies to field applications has significant implications for environmental remediation and sustainable agriculture. This comprehensive review synthesizes current knowledge on BNM fabrication, modification, applications, and research gaps to provide a foundation and future research agenda for their sustainable translation from lab to field. BNMs exhibit unique properties, such as high surface area of 50–500 m2/g, porosity of 0.2–0.7 cm3/g, and abundant oxygen-containing surface groups, enabling effective pollutant adsorption. Various feedstocks, including agricultural waste, sewage sludge, and manure, and thermochemical processes can be used to produce BNMs, while modification techniques, such as acid/alkali treatment, metal oxide incorporation, and biological modification, can further enhance their properties and pollutant removal efficiency. BNMs have demonstrated impressive contaminant removal capabilities in laboratory studies, often exceeding those of unmodified biochars by several fold. In agricultural applications, BNMs have shown potential to improve plant growth, soil fertility, and disease resistance. However, critical knowledge gaps exist regarding the real-world efficacy, safety, and sustainability of BNMs. Priority research directions include optimizing production and modification processes, investigating adsorption kinetics and binding mechanisms, conducting pilot-scale trials, and evaluating potential negative impacts. To facilitate the responsible translation of BNMs from laboratory to field, interdisciplinary collaboration, standardized testing protocols, and comprehensive ecological risk assessments are needed. By addressing these research gaps and prioritizing environmental and health safeguards, the sustainable deployment of BNMs can be achieved, offering a promising solution for restoring degraded environments and supporting sustainable food production. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of biochar with tunable porosity and chemisorption sites is fabricated. • NSC-1.0 could remove up to 1480.1 mg g−1 of tetracycline hydrochloride at 303 K. • DFT calculations confirm that potential chemisorption sites favour adsorption. • The adsorption mechanism involves multiple physico-chemical interactions. • The prospects of NSC-1.0 as a candidate adsorbent are evaluated. The misuse of tetracycline hydrochloride (TCH) antibiotics has caused irreversible hazards to ecosystem. In this study, a series of porous biochar with tunable micro-mesoporosity and chemisorption sites are designed by cleverly exploiting the pyrolysis properties of active agents in various temperature regions. Benefiting from the existence of more pore structures matching the adsorbate while exposing more chemisorption sites, the maximum adsorption capacity (Q m) of NSC-1.0 for TCH is up to 1480.1 mg g−1 at 303 K. A combination of model fitting, post characterization and density functional theory (DFT) calculations confirms that the adsorption process involves the pore filling, the formation of non-covalent bonds (weak hydrogen bond, π-π stacking, electrostatic interaction) and ligand covalent bonding (Lewis acid-base interaction). The Q m is positively correlated with the volume of pore size greater than 1 nm (R2 = 0.9879), indicating that the pore filling effect is a decisive factor for adsorption performance. Post-characterization directly demonstrates that weak hydrogen bonding and π-π stacking are pivotal physical interactions for adsorption. DFT calculations show that partial N, S species and oxygen-containing functional groups can significantly reduce the adsorption energy of intrinsic graphene, especially the chemisorption sites of pyrrolic N (N5) and thiophene S (S5) containing lone-pair electrons. Furthermore, the competitiveness of NSC-1.0 is revealed in practical evaluation, including cation strength, regenerability, actual water source and fixed-bed column. This study not only contributes new insights to synergistically enhance the removal of macromolecular antibiotics by coupling matchable pore sizes and chemisorption sites, but also develops theoretical support for the fabrication of such efficient adsorbents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar-based atomic Fe catalyst was prepared via co-pyrolysis strategy. • Fe-pyridinic N 4 was obtained by co-pyrolyzing biochar and SOFs with Fe-N 3 moiety. • Fe-MCA@SS/PMS system could effectively remove 94.5 % aniline within 5 min. • Mediated electron transfer via [Fe-N 4 /PMS]* mainly accounted for aniline removal. Pollution of groundwater by electron-rich refractory organic pollutants (e-ROPs) is detrimental to ecological integrity and human health. Biochar (BC)-based single-atom Fe catalysts (Fe–SACs) triggering nonradical peroxymonosulfate (PMS) process has shown great potential in addressing this problem. Nevertheless, the successful formation and precise regulation of active sites on BC remain formidable challenges. Herein, co-pyrolysis of BC derived from shrimp shells and N-containing supramolecular organic frameworks with a hexagonal cavity structure of Fe3+–N 3 (Fe–SOFs) was, for the first time, used to prepare an efficient and inexpensive BC-based Fe–SAC (Fe–MCA@SS). The Fe–N bond was successfully grafted from Fe–SOFs onto BC and subsequently transformed into monoatomic Fe–pyridinic N 4. Moreover, Fe–MCA@SS successfully triggered an efficient nonradical PMS process, degrading 94.5 % of aniline (AN) within 5 min. Mediated electron transfer (MET) mechanism was primarily responsible for AN removal. MET was attributed to the following factors: the synergistic effect of the stronger chemical adsorption of PMS with an Fe atom in Fe–pyridinic N 4 active sites, the higher redox potential of [Fe–MCA@SS/PMS]*, and the value of the lowest unoccupied molecular orbital of AN being larger than the value of highest occupied molecular orbital of [Fe–MCA@SS/PMS]*. This study sheds new light on the preparation of BC-based SACs catalyst with efficient nonradical oxidation ability and an excellent feasibility to remove electron-rich organic pollutants in groundwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Use low-cost, readily available carbon sources. • The adsorption capacity of subjectively regulated biochar was 8.06 times higher than that of unactivated. • CoFe 2 O 4 @PBC 1.0 catalyst efficiently activated PMS, 20 mg/L of BPA was completely degraded in 30 min. • Suitable for a wide pH range (3-11) and degrades 100% of BPA in only 9 min at pH=11. • High concentration (200 mM) anionic environment hardly inhibits the degradation of BPA. • In liquid flow device, the degradation efficiency is still 80% at 40 h. Multiphase catalysts with wide pH, high environmental adaptability, and high activity are urgently needed for the water's contaminants to break down. In this study, the biomass waste bamboo leaves were used as the carbon source and activated by KOH to further increase the active sites (the adsorption capacity was 8.06 times that of the unactivated material) loaded with cobalt ferrite composite catalyst CoFe 2 O 4 @PBC X , which could effectively activate the PMS to realize the degradation of BPA. The CoFe 2 O 4 @PBC X + PMS system demonstrated remarkable BPA degradation across a broad starting pH range (3–11), and 100% BPA removal was achieved in 9 min at pH=11. CoFe 2 O 4 @PBC X achieved excellent BPA removal performance under high salinity conditions (200 mM). The toxicity of BPA and its oxidation intermediates was predicted by the ECOSAR model, which proved that BPA was eventually degraded into non-toxic products. In the bisphenol A degradation device, no catalyst deactivation was observed after 14 h, and 80% removal was maintained after 40 h. This study showed that the synthesized CoFe 2 O 4 @PBC X is a highly efficient PMS activation catalyst, which has the potential of low cost, high efficiency, and ecological friendliness in practical wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Functionalized biochars were synthesized via ball milling-assisted modification process. • Hydrogen bonds were crucial in facilitating adsorption of SMX and CBZ. • Surface functional groups of BC are dominant in pollutants degradation. • SMX and CBZ degradation mechanisms are critically discussed. In this study, orange peel biochar (OPBC) was synthesized through a pyrolysis process. Decoration with two specific functional groups (i.e., –COOH and NH 2) was performed through a ball milling-assisted modification process to yield the respective biochars (i.e., OPBC-COOH and OPBC-NH 2). Both OPBC-COOH and OPBC-NH 2 demonstrated excellent adsorption capacities for sulfamethoxazole (SMX) and carbamazepine (CBZ), and hydrogen bonding between the pharmaceuticals and BCs followed the primary adsorption mechanism. In addition, both OPBC-COOH and OPBC-NH 2 (0.3 g/L) exhibited high degradation efficiencies for SMX (10 mg/L, 87 %; 92 %) and CBZ (10 mg/L, 73 %; 83 %) when peroxymonosulfate (PMS, 1 mM) was present. The scavenging experiments confirmed that electron transfer and radical/non-radical pathways (·OH and 1O 2) are mainly responsible for the degradation of SMX and CBZ, respectively. It was also proven that the oxygen- and nitrogen-containing surface functional groups on BC are important for activating PMS for the degradation of organic pollutants. These findings provide new insights into the effects of functional groups on BC for the degradation of contaminants of emerging concern. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-doped biochar (non-metallic heteroatoms and transition metal oxides) was prepared. • Constructing multi-pathway electron transfer channels (C-N, C-O-Cu and N-Cu bonds). • Dissolved oxygen modulated by CNB-500 tended to exist as Pauling configuration. • A strong radical-unradical synergy was demonstrated in CNB-500-PS system. The aim of this paper is to investigate the catalytic activity, the mechanism on degrading tetracycline (TC) with co-doped biochar modifying with non-metallic heteroatoms and transition metal oxides in a persulfate (PS) system. To this end, we ingeniously prepared nitrogen and copper oxide co-doped biochar (CNB-500) and activated it with PS to develop a CNB-500-PS system that can efficiently degrade TC. Owing to constructing a multi-pathway electron transfer channel, the non-radical interaction-electron transfer in the system was enhanced; the surface charge distribution of the catalyst was broken, and its adsorption with dissolved oxygen in water was regulated towards induce the generation of singlet oxygen (1O 2); the mechanism on radical-non-radical synergism was elucidated, and the possible degradation pathways for TC were speculated. Therefore, the CNB-500-PS system provides a new strategy for degrading antibiotics in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mechanism of KBBC/PS system for mining water treatment under different pH conditions was studied. • Direct electron transfer process contributed under acidic and neutral conditions. • Various active species contributed under alkaline conditions. • Continuous flow experiments prove the potential applicability of KBBC/PS process. The challenges of remediating polluted water in mine areas are exacerbated by low emission dispersion and long-lasting pollution, particularly the significant fluctuations in pH value. Notably, the treatment of flotation reagent polluted water with variable pH scenarios remains a challenge. In this study, metal-free biochar-based materials (KBBC)/persulfate system was used for flotation reagent contaminated wastewater treatment with a wide pH range. Regarding the intrinsic nature of the biochar-based materials, ball milling enhanced the degree of graphitization, while introducing a hard template of KCl increased the proportion of carbonyl functional groups on their surface, thereby facilitating persulfate activation. Experimental findings revealed that the KBBC/PS system displayed efficient degradation of aniline aerofloat (AAF) as a representative flotation reagent across a wide pH range (pH = 3.6–10.4 with buffer). Investigations on the mechanism indicated that, under acidic and neutral conditions, superoxide radicals and direct electron transfer processes constituted primary pathways for pollutant degradation. Meanwhile, various active species contributed under alkaline conditions with increased involvement of free radicals (•OH and SO 4 •−) and singlet oxygen. Furthermore, continuous flow experiments were set up to prove the potential applicability of the KBBC/PS process. This study not only deepens the understanding of persulfate activation by metal-free carbon-based materials across a wide pH range but also expands their potential applications in mine-polluted water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nickel phosphide/biochar (Ni x P/biochar) is synthesized utilizing phytic acid (PA). • Ni x P/biochar efficiently activates persulfate (PS) for tetracycline removal (94.55%). • The surface-bound radicals are the predominant reactive oxygen species (ROSs). • Biochar alters the catalytic selectivity of Ni x P and electron donations of elements. Exploring efficient and cost-effective heterogeneous persulfate (PS) oxidation systems is meaningful for addressing recalcitrant organic pollutants in wastewater. Herein, nickel phosphide/biochar (Ni x P/biochar) composite, with Ni 12 P 5 as the predominant crystalline phase, is firstly synthesized utilizing a biomass phosphorus source, phytic acid (PA). Ni x P/biochar demonstrates outstanding catalytic capacity in activating PS for removing tetracycline (TC). At 1 mM PS, 0.15 g/L catalyst, and pH 7.0, 94.55 % of TC (20 mg/L) can be removed within 180 min, markedly superior to Fe-, Cu-, and Co-based phosphide/biochar composites. The Ni x P/biochar-PS system exhibits superior catalytic degradation efficiency (>94.00 %) against varying concentrations (1–20 mg/L) of TC and robustly resists interferences from complex water matrices, including sodium humate solution, surface water, anions (>90.00 %). The ideal catalytic efficiency is ascribed to surface-bound radicals (including SO 4 -• and •OH), with •O 2 – and 1O 2 assisting in. Density functional theory (DFT) calculations indicate that due to the electron donations from Ni, P, and C, S 2 O 8 2- may undergo homolysis to produce the surface-bound SO 4 -•, which may induce the generation of other reactive oxygen species (ROSs) through radical chain reactions. Besides, the electronic structures and work functions of Ni x P in Ni x P/biochar composites can be modulated by the biochar, enhancing the catalytic selectivity of NiP, Ni 2 P, and Ni 12 P 5 with Ni as the electron-donating center, while diminishing that of P-centered Ni 3 P. These findings may serve as a reference for the theoretical study of Ni-based catalysts and the practical application of Ni x P in AOPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unique porous structure promotes mass transfer process to accelerate reaction kinetics. • N defect regulates the local electron density of active center Ni to enhance CO 2 adsorption. • Nitrogen atoms anchor Ni sites accurately, exposing more catalytic active sites. • Evaluating the optimal performance of the catalyst by changing the mass ratio and preparation temperature. Molecular catalysts have been receiving extensive attention due to their explicit, designable, easily modifiable molecular structures and tunable catalytic active sites, which exhibit elegant electrocatalytic performance in electrocatalytic carbon dioxide reduction reactions. However, the susceptibility to aggregation due to strong intermolecular π-π interactions among the metal bipyridines, phthalocyanines and porphyrins among the molecular catalysts limits their catalytic performance. Herein, an active catalyst nickel phthalocyanine anchored N-doped ball milled biochar (NiPc/N-BMBC) was developed with highly enriched pore structure and high surface area for electrocatalytic CO 2 reduction reaction. On the nanoscale, NiPc molecules were uniformly anchored on N-BMBC to enhance the dispersion, exposing sufficient catalytic active sites. Concretely, the catalyst NiPc/N-BMBC exhibited extraordinary performance in the electrolytic conversion of CO 2 reduction reaction, with a Faredaic efficiency of CO (FE CO) > 70 % at an overpotential (−0.75 to −0.95 V vs. RHE) and a high CO partial current density (j CO) of 96 mA cm−2 at −1.0 V vs. RHE, which were much higher than that of NiPc (24 %, 38 mA cm−2) and N-BMBC (9 %, 2 mA cm−2). This work provides a new insight in the structural design of carbon-based electrocatalyst for efficient electrocatalytic CO 2 reduction reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successful saccharification of CMR using sulfonated biochar derived from pomelo peel. • Elucidation of the fundamental characteristics of sulfonated biochar derived from pomelo peel. • Elucidation of the process variations during the hydrolysis of CMR along with the influence of key reaction conditions on the resulting products. • The role played by the hydrolysate of CMR in the cultivation process of Oocystis. sp. was revealed. The conversion of waste into high-value products has long been a focus point of research in green and sustainable chemistry. In this study, a novel value-adding strategy was devised to not only facilitate the resource utilization of biomass waste like Chinese medicine residue (CMR) and pomelo peel but also contribute to the advancement of microalgae cultivation. Sulfonated biochar PP-700-S was synthesized from pomelo peel waste, and its morphology and structural characteristics were analyzed. An effective method for the hydrolysis of CMR using PP-700-S as a catalyst in the aqueous phase was then explored, with a thorough investigation of the process and key influencing factors. Under the reaction conditions of 130 °C, 24 h, 20 mL H 2 O, CMR: PP-700-S = 1: 1, a 51.87 % yield of reducing sugars was directly obtained from the CMR, with PP-700-S exhibiting the selectivity of glucose production. Subsequently, the hydrolysate (HL-CMR) was utilized as a growth medium for microalgae, revealing that the presence of HL-CMR enhanced the nutrient balance in the medium, creating a more conducive environment for microalgae growth. Overall, this study presents a sustainable and efficient pathway for the utilization of lignocellulosic waste, facilitating the conversion of waste into higher-value products and contributing to the development of a green and sustainable science. [ABSTRACT FROM AUTHOR]

[Display omitted] • Petal-Like LaCO 3 OH on biochar efficiently captures low concentration phosphorus. • New adsorbent shows superior pH tolerance compared to other biochars. • La-BC has an excellent selective adsorption for phosphorus in water. • The mechanisms in low and high concentration phosphorus adsorption were deciphered. Effectively managing phosphorus (P) concentrations in waterbody is essential to curb eutrophication. In this study, we employed wetland plant Canna indica straw to create biochar and synthesized a distinctive two-dimensional (2D) petal-shaped LaCO 3 OH biochar adsorbent (La-BC). This novel material exhibited outstanding adsorption capabilities for capturing low-concentration P, surpassing unmodified BC by 2–4 times. La-BC showed a rapid adsorption capacity, achieving 97.01 % to 99.10 % removal efficiency within 10 h for 0.5 mg/L and 1.0 mg/L P concentrations. Its maximum P adsorption capacity was recorded at 129.4 mg/g. Considering both environmental safety and P removal efficiency, the optimal pH range for La-BC is 4.0 to 11.0. Adsorption experiments have demonstrated that the adsorption mechanism involves electrostatic attraction and ligand exchange under acidic conditions, with ligand exchange predominating in alkaline environments. Density Functional Theory (DFT) demonstrated that the absolute value of adsorption energy (E ads) is as followed: HPO 4 2− (2.43) > H 2 PO 4 − (2.27) > humic acid (0.613), indicates that La-BC preferentially saturated adsorbs HPO 4 2−, H 2 PO 4 − and then adsorbs humic acid (HA). When the concentration of HA reaches 50 mg/L, which is 50–100 times higher than the P, the removal rate of P by La-BC decreases slightly, but it is still higher than 90 %. La-BC exhibits excellent adsorption selectivity towards P, with no interference from co-existing anions (Cl−, NO 3 –, SO 4 2−, CO 3 2–) in water. Our findings provided a highly efficient, pH-stable, and promising biochar-based solution for the removal of low concentrations of P. [ABSTRACT FROM AUTHOR]

• Biochar could significantly improve AD performance of Maotai flavor Baijiu wastewater. • Joint modification could significantly enhance the electron donating capacity. • Enrichment of electroactive microorganisms was a prerequisite for enhancing the DIET. • Syntrophomonas had a tenfold increase in relative abundance by biochar. • The assistance of biochar changed the pathway of methane production. The low pH of Maotai-flavor Baijiu wastewater (MFBW) adversely affects its anaerobic digestion (AD) performance, resulting in low AD efficiency. Here, coconut shell was used to produce biochar. The characteristics of biochar were regulated through acid, alkali, and magnetic modification, respectively. Biochar and modified biochars were applied to assist the AD of MFBW. The results showed that biochar could significantly increase methane yield by 220.8 %–241.7 % with the corresponding soluble chemical oxygen demand (sCOD) degradation increasing by 52.3 %–57.5 % (p < 0.05). Joint modification could significantly enhance the electron donating capacity from 0.0042 to 0.0095 mmol e−1/g (p < 0.05). The combined modification with magnetic alkali had the best stimulating effect on the AD process, which might be related to the conductive particles (Fe 3 O 4) formed during magnetization processes. The modified biochar featured a high degree of surface roughness, a relatively large aperture, and strong electron donating ability, all of which were beneficial to the colonization and microbial growth. Supplementation with biochar resulted in the enrichment of Proteobacteria, Firmicutes, and Actinobacteria, especially for Syntrophomonas (rising from 0.013 % to 6.74 %–10.93 % of relative abundance). These microorganisms are related to the hydrolysis, acidification, and extracellular electron transfer. The enrichment of electroactive microorganism is a prerequisite for improving the direct interspecies electron transfer pathway. This study provides theoretical support for efficient MFBW treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The porous PBC PB was successfully synthesized by one-step KHCO 3 -activated pyrolysis. • The PBC PB has excellent passivation performance with a high S BET of 1342.07 m2/g. • PBC PB could significantly reduce the bioavailability and bioaccumulation of Pb/Cd. • Precipitation, complexation and cation-π interaction convert Pb/Cd to stable species. The porous biochar (PBC PB) was prepared by one-step KHCO 3 -activated pyrolysis of corn stalks, which showed excellent passivation properties for Pb/Cd in soil (48.99 % or 46.74 %). Characterization results revealed that the PBC PB possessed a dense and network-like pore structure with a huge specific surface area of 1342.07 m2/g, which was conducive to the passivation of Pb/Cd. Batch experiments showed that PBC PB had excellent adsorption properties with the maximum absorption capacity of 117.61/48.24 mg/g. After 30 d of remediation, the bioavailable-Pb/Cd contents in 5.0 % of PBC PB treatment were reduced by 47.06 % and 58.42 %, respectively. The speciation transformation results uncovered that the contents of unstable Pb/Cd components gradually decreased with the increase of PBC PB dosages, ultimately transforming into stable residual components. In addition, the PBC PB could effectively increase the contents of soil available nutrients and enhance functional enzyme activities, which contributed to promoting the growth of cucumber seedlings. Meanwhile, PBC PB strongly alleviated the oxidative damage of Pb/Cd to cucumber seedlings by significantly reducing the Pb/Cd accumulation and antioxidant oxidase activity of cucumber seedlings. Furthermore, precipitation, complexation, as well as cation-π interaction were the primary passivation mechanisms of PBC PB for Pb/Cd. Overall, the study provided a reasonable design of porous carbon-based materials for the remediation of Pb/Cd-contaminated soil. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel biocatalyst BFMO@BC was successfully synthesized. • 1O 2 was evidenced as the dominant reactive oxidizing species. • BFMO@BC was environmentally adaptable and exhibited excellent cycling properties. • The bimetallic cycle, C=O groups, and carbon defects were responsible for the superior catalytic activity. Biogenic metal oxides are considered superior eco-friendly candidates for peroxymonosulfate (PMS) activation. However, they often suffer from metal aggregation, high ion leaching, and poor recyclability, diminishing their practical attractiveness. In this study a novel biochar-loaded biogenic iron-manganese oxide composite (BFMO@BC) was synthesized to activate PMS for sulfamethoxazole (SMX) degradation. The introduction of biochar brought more active sites (C=O and carbon degree), promoted the bimetallic redox cycle between Fe and Mn, and facilitated the conversion of SO 5 •− to 1O 2 , which significantly improved the catalytic performance. Results demonstrated 100 % SMX degradation within 3 min in BFMO@BC/PMS system. And the reaction rate constant of this system was as high as 0.852 min−1, which was 11.6 times than that of BFMO/PMS. Moreover, high SMX removal efficiencies (near 100 %) could be obtained over a wide pH range (3–11) and in complex water matrices. BFMO@BC displayed excellent adaptability, stability, and reusability for SMX removal. This study provides new insights into the utilization of biocatalysts in advanced oxidation processes for pollutant degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar-ferrospinel AFe 2 O 4 nanocomposites were synthesized for PAA activation. • The applied AOP system efficiently degraded CBZ and other PhACs under mild conditions. • CH 3 C(O)OO radicals were identified the dominant active species for CBZ degradation. • Excellent stability and magnetic separability of biochar-CoFe 2 O 4 were observed. • Mechanistic studies were performed using techniques such as In-situ ATR-FTIR. Peracetic acid (PAA)-based advanced oxidation processes (AOPs) are promising technologies for the efficient treatment of persistent contaminants in wastewater. In this study, three different magnetic biochar (BC)-ferrospinel AFe 2 O 4 (A = Cu, Co, or Mn) nanocomposites were synthesized through a combined sol–gel/pyrolysis process for the activation of PAA to degrade carbamazepine (CBZ). The following order of efficiency was observed for CBZ degradation in the presence of PAA: BC-CoFe 2 O 4 (100 %) > BC-MnFe 2 O 4 (7 %) ≈ BC-CuFe 2 O 4 (7 %). In addition, 0.8 mM PAA, 0.3 g/L catalyst, nearly neutral pH, and 333 K were identified as the optimal operating parameters for the degradation of 1 mg/L CBZ in the BC-CoFe 2 O 4 /PAA system. Mechanistic studies revealed that CH 3 C(O)OO radicals are the dominant active species for the degradation of CBZ in the BC-CoFe 2 O 4 /PAA system, and the continuous conversion of Co(II) to Co(III) in this system is responsible for the generation of these radicals. In addition, the water matrices (e.g., humic acid (20 mg/L), NaCl (0.05 M), and NaNO 3 (0.01 M)) played negligible roles in the degradation of CBZ in the BC-CoFe 2 O 4 /PAA system. This system exhibited highly selective and reactive degradation of organic pollutants with electron-rich groups (e.g., CBZ (0.36 min−1), sulfamethoxazole (0.12 min−1), and diclofenac (0.28 min−1)). Furthermore, the degradation products of CBZ were identified, and possible degradation pathways and toxicity of these transformation products were proposed. The BC-CoFe 2 O 4 /PAA system demonstrated outstanding degradation performance in dynamic systems and real wastewater treatment applications. This study describes the performance of an efficient and easy-to-separate catalyst for the activation of PAA. This study facilitates the development and application of PAA-based AOPs for wastewater treatment. [ABSTRACT FROM AUTHOR]

• Na 2 S 2 O 4 , biochar, and micron iron were reunited by wet and dry ball milling. • Wet ball milling promoted faster and complete Cr(VI) removal (100 % in 80 min) • The composite of wet ball milling presented excellent anti-ageing property. • Higher electron selectivity was obtained (59.15% for wet and 46.72% for dry) • Replacing oxides with sulfides facilitated high iron cycling for Cr(VI) removal. Obstacles such as aggregation and low activity of micron zero-valent iron in pollutant treatment could be overcome by sulfidation and biochar support. Ball milling is a promising method for the preparation of iron-based composites but the milling atmosphere is critical. To maximize the reactivity and identify the effects of ball mill atmosphere, ball milling technology under wet and dry atmosphere was applied to prepare composites from mZVI, Na 2 S 2 O 4 , and pine wood biochar (BC) for Cr(VI) removal. The results showed that S-mZVI/BC-wet was highly dispersible with more FeS 2 coverage and thus more efficient on Cr (VI) removal than S-mZVI/BC-dry (99.9 % removal in 80 min vs. 87.9 % removal in 24 h) at the optimum Fe: C mass ratio (1:1), S: Fe molar ratio (1:10), and reaction conditions. Cr(VI) was adsorbed by a spontaneous, endothermic mechanism that combined physisorption and chemisorption. The reduction process was vulcanization efficiency and iron cycle dependent. Reduction outperformed adsorption on the Cr(VI) removal and high reduction rateswere electron-selectively related (59.15 % for S-mZVI/BC-wet and 46.72 % for S-mZVI/BC-dry), implying S-mZVI/BC-wet was more capable. S-mZVI/BC-wet presented excellent anti-ageing property and slightly inferior regeneration performance. In conclusion, the composite prepared by wet ball milling have excellent performance in rapid and complete removal of Cr(VI), and S-mZVI/BC-wet has superior potential in acidic wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A philic-CO 2 supercarbon was derived from rice husk waste by a new process. • It possessed the max specific surface area in reported biochars (4230 m2 g−1) • It possessed the max CO 2 uptake capacity in the reported biochars (341.5 mg g−1) • This study gave a new way to generate rich ultra-micropores and C-F groups in char. A super-carbon material as adsorbents of CO 2 were prepared with rice husk waste by a new two-step process, pyrolysis-activation and HF post-desilication process. This paper was focused on investigating the boosting effect and mechanism of post-desilication. It was found that the function of the post-desilication was considerably different from that of the reported pre-desilication. It could not only effectively remove Si element from rice husk biochar (RHC) but also significantly improve its performance, producing a super-biocarbon with a well-developed pore structure, rich C-F groups, and a 4230-m2 g−1 surface area, which is the max surface area of known biocarbon. It could adsorb 341.5 mg g−1 CO 2 , a max CO 2 adsorption capacity of reported biocarbon, and its CO 2 /N 2 and CO 2 /H 2 O adsorption selectivity index reached as high as 22.2 and 2.1, respectively. The large surface area was mainly originated from the expansion effect of SiF 4 gas from the post-desilication, generating numerous ultra-microspores, while these C-F groups were generated by the co-reactions of the post-desilication. The ultra-high adsorption capacity was mainly from the fill-adsorption driven by the size effect of these ultra-micropores and the strong CO 2 -affinity of C-F groups, and the adsorption selectivity was confirmed to depend on water-resistant and CO 2 -philic characteristics of its C-F groups by theoretical calculations and experimental observations. These findings presented not only an advanced CO 2 -capture material but also a facile way to tailor textural structure of other biochars. [ABSTRACT FROM AUTHOR]

[Display omitted] • Turn C. glomerata alga from environmental issue to strong membrane modifier. • Functionalizing biochar by MOF to attain modifier of advanced characteristics. • Significant salts and dye rejections achieved by the modified MMMs. • Water flux and fouling resistance enhanced by the incorporation of novel modifiers. • Long-term stability of PES MMMs was achieved when modified by novel modifiers. UiO-66-NH 2 metal–organic framework nanoparticles and carbonaceous biochar prepared from the pyrolysis of Cladophora glomerata alga are introduced as novel modifiers and employed to manipulate polyethersulfone (PES) mixed matrix membranes. The membranes were fabricated through immersion precipitation method and fully assessed through X-ray diffraction pattern, field emission scanning electron microscopy, contact angle, atomic force microscopy, and zeta potential analysis. The membrane performances were also examined by water flux, fouling resistance, and solute rejection. The results indicated that the modified membranes manipulated by 0.2–0.8 wt% of modifier had smoother surfaces than the pristine PES membrane. Moreover, by loading the modifiers in the membrane bulk, the zeta potential was changed from negative to positive values. All the modified membranes revealed superior filtration performance compared to that of the pristine PES membrane. In the modified membrane of the best performance, water flux was increased to up to 85% and contact angle was decreased to 43°. Due to the uniform distribution of modifiers on the membrane surface, and thereby, formation of a barrier layer, up to 98.5% of Reactive Blue 50 dye was rejected by the modified membranes. Salt rejections were also improved in the membranes tailored by the introduced modifiers. Furthermore, through the fouling experiments conducted by humic acid and bovine serum albumin, just 12.9 and 34% reductions in water fluxes were recorded for the modified membrane of the best performance. The experimental results indicated that the higher flux recovery ratios could also be expected for all the membranes modified by the novel hydrophilic modifiers. [ABSTRACT FROM AUTHOR]

[Display omitted] • BC/ZnO composites were successfully synthesized from wood wastes. • The BC/30 %ZnO composite showed enhanced photocatalytic performance than pure ZnO. • The composite presented good reusability and stability after 4 cycles of use. • First study applied BC/ZnO composite for NAs mixture photocatalytic degradation. • Over 95 % of NAs in mixture were degraded by BC/30 %ZnO after 6 h solar irradiation. Naphthenic acids (NAs) present in oil sands process water (OSPW) have brought increasing environmental concerns due to their potential risk to aquatic and mammalian species. In this study, sustainable biochar zinc oxide (BC/ZnO) composites were synthesized using wood waste with different ZnO content and applied under simulated solar light for the photocatalytic degradation of different NAs for the first time. The best experimental conditions were determined as 0.5 g/L BC/30%ZnO and 4 h of simulated solar irradiation time, achieving 93.7 % degradation of cyclohexanecarboxylic acid (CHA) following the pseudo-first order kinetics. BC, with a porous structure and roughened surface, acted as an excellent platform for ZnO particles and an electron reservoir to inhibit the recombination of photogenerated electron-hole pairs. Hydroxyl radicals (•OH) were identified to play the dominant role in CHA degradation, and the enhanced photocatalytic performance of the BC/30%ZnO composite was proved by more •OH species detected compared to synthesized ZnO. The composite showed good reusability and stability after 4 successive cycles of use, still achieving 92.9 % degradation of CHA. Moreover, this is the first study applying BC/30%ZnO composite for the simultaneous degradation of a complex mixture of eight NAs with significantly different chemical structures. The competition kinetics were observed among different NAs in the mixture, resulted in over 95 % degradation of total NAs after 6 h treatment. By applying wood waste-based BC/ZnO composite with excellent photocatalytic performance in combination with solar light as green energy source, this research highlights a promising sustainable approach for real OSPW remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe(II)-bearing minerals alone are non-reactive to trichloroethylene reduction. • Fe(II)-bone char could effectively reduce trichloroethylene to acetylene. • The Fe(II)-bone char were prepared by simple mixing in water. • Fast kinetics did not guarantee high electron efficiency. • Suitable crystallinity of Fe(II) enable steady and long lasting TCE reduction. Fe(II)-bearing minerals might be able to drive the attenuation of chlorinated ethene in soil and groundwater, however, with relatively slow kinetics. In this study, bone char(BC) was selected as an efficient and benign catalyst to prepare composites with three different Fe(II)-bearing minerals (Green rust (GR), Fe(OH) 2 and FeS), respectively, for enhanced trichloroethylene (TCE) dehalogenation. The kinetics experiment demonstrated that the presence of BC could effectively switch on the TCE dehalogenation by these solids, while these Fe(II)-bearing minerals alone can barely reduce any TCE. Surprisingly, the Fe(OH) 2 -BC showed fastest TCE reduction rate, followed by GR-BC and FeS-BC in sequence. Acetylene was confirmed as the major dehalogenation products while other chlorinated byproducts were hardly detected. The electron efficiency (η e) for TCE reduction was further calculated and compared among these BC amended systems, the results show that the highest η e value was recorded in GR-BC system as 33.14% with high loading of TCE. Solid phase characterization confirmed that the high loading of amorphous Fe(II) on the BC surface might effectively improve the TCE dehalogenation kinetics, while the well crystallized Fe(II)-bearing minerals would increase the electron efficiency. According to this mechanism, it might be possible to achieve balance between kinetics and electron efficiency. Stress resistance test in real groundwater matrix and life cycle analysis (LCA) was conducted to further verify the application potential of these composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • BC-SIPN particles selectively adsorb TlOH (aq) , easing Tl concentration dependence. • Hydrogen bonding-electrostatic interactions formed between TlOH (aq) and BC-SIPN. • SIPN enhances particle stability, extending lifetime for sustained efficacy. • Electro-induction directly oxidizes Tl(I) to Tl(III) by BEC on BC-SIPN particles. • Gel-minerals with 0.073 % Tl content exhibit recycling potential. Electrochemical techniques for thallium (Tl) treatment face a substantial challenge linked to the concentration of Tl(I), hindering the efficient removal and recovery of trace Tl(I) (μg L−1). In response, we synthesized hydrogel particles incorporating biochar (BC) within semi-interpenetrating polymer networks (SIPN), showcasing robust selectivity for Tl(I). These biochar-embedded-SIPN hydrogel particles (BC-SIPN particles), employed as dispersed electrodes, facilitated the targeted oxidation and enrichment of Tl(I) through electro-induction. Research outcomes elucidate the adept mitigation of the "efficiency-dependent concentration" behavior by electro-induced BC-SIPN particles during the reaction process. Under optimized conditions (pH 12, 2 V cm−1, 30 min), Tl(I) removal efficiency surpassed 98 % at an initial concentration of 100 μg L−1. The SIPN structure enhanced particle stability, and after seven cycles of enrichment in a 100 μg L−1 Tl(I) environment, BC-SIPN particles achieved a Tl content of 0.073 %, meeting Tl mineral content standards and promoting the recovery of scarce Tl resources. First-principles calculations underscore the pivotal role of hydrogen bond-electrostatic interactions between TlOH (aq) and particles in driving selective Tl(I) adsorption. Insights from quenching and capture reactions reveal a predominant direct oxidation pathway of Tl(I) to Tl(Ⅲ), complemented by indirect oxidation driven by reactive oxygen species, including OH, O- 2 and 1O 2. This study presents an innovative approach for trace Tl(I) wastewater treatment, simultaneously mitigating the "efficiency-dependent concentration" phenomenon, and underscores the transformative potential of electro-induced BC-SIPN hydrogel particles in offering sustainable solutions for Tl(I) removal and resource recovery in environmental stewardship. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biochar composite (ZnS/NBC) was successfully synthesized by one-step pyrolysis of the mixture of Porphyra and ZnCl 2. • ZnS/NBC 10 held high specific surface area, highly graphitized structure and strong photothermal conversion ability. • ZnS/NBC 10 /PMS/light system showed high degradation rate and nearly complete mineralization of CBZ. • The dominant role of 1O 2 , the SO 4 −, OH and electron transfer assist jointly enhanced the degradation of CBZ. • CBZ degradation pathway was proposed based on Fukui index calculations and LC-MS results. Heterogeneous catalysis with peroxymonosulfate (PMS) activation has received increasing attention in recalcitrant contaminants treatment, but multidimensional coupling via engineered biochar materials and photothermal synergy is still rare. Herein, we reported photothermal-synergistic PMS activation by Porphyra -derived porous biochar composites (ZnS/NBC) for carbamazepine (CBZ) degradation. Benefitting from the high specific surface area, highly graphitic structure and strong light-to-heat conversion ability, ZnS/NBC 10 /PMS/light system showed enhanced degradation performance and nearly complete mineralization of CBZ. Meanwhile, this system maintained high degradation efficiency in real water bodies and natural sunlight condition, respectively. Mechanism analysis confirmed that the predominant role of 1O 2 and the auxiliary involvement of SO 4 −, OH and electron transfer jointly contributed to the CBZ degradation. Finally, the possible degradation pathways of CBZ were elaborated based on the liquid chromatography-mass spectrometry results and Fukui index calculations, and the diminishing ecotoxicity of the accompanying degradation intermediate was evaluated using the toxicity estimation software tool. This study provides a new insight for advancing a comprehensive utilization of photothermal conversion and biochar-based PMS activators to organic wastewater purification. [ABSTRACT FROM AUTHOR]

Photogenerated electrons and holes are transferred to g-C 3 N 4 and h-BN, respectively. Biochar acts as an electron transmitter to accelerate electron transport in the heterojunction. Biochar as an electron reservoir and the heterojunction together inhibit the recombination of photogenerated carriers. ·O 2 – and h+ jointly attack the dye azo dye molecules to degrade them. [Display omitted] • BC/h-BN/g-C 3 N 4 with spherical lamellar cluster morphology was synthesized. • Biochar is the excellent electron transfer and storage in BNC. • Biochar made the photoresponse range of photocatalyst appear obvious redshift. • LVRPA, TRPA and τ app of photocatalyst were calculated by SFM model. • Electrons and holes migrated and separated efficiently in BNC. The biochar/h-BN/g-C 3 N 4 (BNC) composite photocatalyst with a spherical sheet cluster structure, was successfully synthesized. Under simulated solar light irradiation, the photocatalytic degradation rate of reactive red 120 by BNC was 87.94 % within 90 min, corresponding to a 3.57-fold higher kinetic constant than that of g-C 3 N 4. The band structure and electron transfer path in BNC were determined using characterizations and density functional theory (DFT) calculations, confirming a type II heterojunction forming. The attraction of h-BN to h+ by electrostatic interaction and biochar's capacity for both electron transfer and storage were confirmed. Doping of biochar was also found to enhance light absorption and provide O vacancy. The existence of piezoelectric effect assisted the movement of photogenerated carriers to the material surface. In the system, the main active oxidation species were h+ and ·O 2 –. By calculating optical characteristics, the practical activity of photocatalysts is evaluated. Results indicated that the optimal dosage of BNC was 0.5 g/L in the planar reactor, corresponding to an optical thickness of 2.61 calculated by the six-flux radiation absorption–scattering model (SFM). Biochar doping was found to enhance light absorption. A novel photocatalytic mechanism was proposed for promising matel-free BNC. [ABSTRACT FROM AUTHOR]

[Display omitted] • S-nZVI-BC/PSSA can simultaneously remove Microcystis aeruginosa and MC-LR. • MC-LR is degraded mainly through the oxidation of SO 4 -• and •OH. • DFT shows that C = C-C = C bond on Adda was more vulnerable to attack by SO 4 -• and •OH. • S-nZVI-BC/PSSA inhibits algae by regulating genes such as ATP and cytochrome. • The degradation pathways of MC-LR are proposed. As a hepatotoxin generated by the excessive proliferation of Microcystis aeruginosa , Microcystin - LR (MC-LR) has posed serious threat to humans and wildlife. In this study, biochar supported sulfide nZVI and persulfate sustained-release agent (S-nZVI-BC/PSSA) were prepared to simultaneously remove MC-LR and Microcystis aeruginosa. Batch experiments showed that the removal efficiency of MC-LR (100 μg/L) by S-nZVI-BC/PSSA could reach 92.0 % when the BC pyrolysis temperature, the Fe/C mass ratio and the Fe/S molar ratio were 700 °C, 1:2 and 40:1, respectively. According to the results of EPR and density functional theory (DFT), the carbon–carbon conjugated diene bond (C = C-C = C) on Adda were most vulnerable to attack by the free radicals such as •OH and SO 4 -• generated by S-nZVI-BC/PSSA. The results of reactor experiments indicated that S-nZVI-BC/PSSA had good removal effect on MC-LR and Microcystis aeruginosa. According to the transcriptome analysis, S-nZVI-BC/PSSA led to the disorder of cell metabolic process by up-regulating ATP and pigment synthesis genes and down-regulating photosynthesis genes, eventually inhibiting the growth of Microcystis aeruginosa and even causing their death. In addition, the up-regulation of biological transport processes could enhance the release of MC-LR from Microcystis aeruginosa , which was completely removed by S-nZVI-BC/PSSA. Moreover, four degradation pathways of MC-LR were analyzed, and the final products were CO 2 and H 2 O. Therefore, this S-nZVI-BC/PSSA system showed great promise for practical applications in the removal of Microcystis aeruginosa and MC-LR. [ABSTRACT FROM AUTHOR]