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In recent times, the application of biochar (BC) as an upcoming catalyst for the elimination of recalcitrant pollutants has been widely explored. Here, an iron loaded bamboo biochar activated peroxymonosulphate (PMS) process was tested for removing Congo red (CR) dye from water medium. The catalyst was synthesized using a green synthesis method using neem extracts and characterized using SEM, FTIR, and XRD. The effects of various operating parameters, including solution pH, catalyst dosage, and pollutant dosage, on dye degradation efficiency were examined. The results showed that at the optimized conditions of 300 mg L−1 PMS concentration, 200 mg L−1 catalyst dosage, and pH 6, about 89.7% of CR dye (initial concentration 10 ppm) was removed at 60 min of operation. Scavenging experiments revealed the significant contribution of O 2 •−, •OH, and 1O 2 for dye degradation, with a major contribution of O 2 •−. The activation of PMS was mainly done by biochar rather than iron (loaded on biochar). The catalyst was highly active even after four cycles. [Display omitted] • Application of green synthesized iron-loaded biochar as a PMS activator. • The superior performance of biochar in the activation by PMS. • O 2.•− is the primary oxidant responsible for dye degradation • •OH and 1O 2 were also produced in the catalyst-activated PMS process • SO 4.•− has less contribution to dye degradation [ABSTRACT FROM AUTHOR]

The presence of heavy metals in water pose a serious threat to both public and environmental health. However, the advances in the application of low cost biochar based adsorbent synthesize from various feedstocks plays an effective role in the of removal heavy metals from water. This study implies the introduction of novel method of converting food waste (FW) to biochar through pyrolysis, examine its physiochemical characteristics, and investigate its adsorption potential for the removal of heavy metals from water. The results revealed that biochar yield decreased from 18.4 % to 14.31 % with increase in pyrolysis temperature from 350 to 550 °C. Likewise, increase in the pyrolysis temperature also resulted in the increase in the ash content from 39.87 % to 42.05 % thus transforming the biochar into alkaline nature (pH 10.17). The structural and chemical compositions of biochar produced at various temperatures (350, 450, and 550 °C) showed a wide range of mineralogical composition, and changes in the concentration of surface functional groups. Similarly, the adsorption potential showed that all the produced biochar effectively removed the selected heavy metals from wastewater. However a slightly high removal capacity was observed for biochar produced at 550 °C that was credited to the alkaline nature, negatively charged biochar active sites due to O-containing functional groups and swelling behavior. The results also showed that the maximum adsorption was recorded at pH 8 at adsorbent dose of 2.5 g L−1 with the contact time of 120 min. To express the adsorption equilibrium, the results were subjected to Langmuir and Freundlich isotherms and correlation coefficient implies that the adsorption process follows the Freundlich adsorption isotherm. The findings of this study suggest the suitability of the novel FW derived biochar as an effective and low cost adsorbent for the removal of heavy metals form wastewater. [Display omitted] • Biochar was successfully produced from food waste at various pyrolysis temperatures. • Temperatures significantly affect the physiochemical characteristics of biochar. • Biochar showed effective adsorption capacity towards the removal of heavy metals. • pH 8, 2.5 g L−1 adsorbent dose and 120 min contact time showed high adsorption. • Adsorption equilibrium fitted best with Freundlich adsorption isotherm model. [ABSTRACT FROM AUTHOR]

An important paradigm shift towards the circular economy is to prioritize waste prevention, reuse, recycling, and recovery before disposal is necessary. In this context, a sustainable protocol of converting waste pea peel (wPP) into low-cost carbon nanomaterials for sensing and conversion of p -nitrophenol (p -NP) into value-added paracetamol is being reported. Two fractions of the carbonaceous nanomaterials were obtained after the hydrothermal treatment (HT) of wPP, firstly an aqueous portion containing water-soluble carbon dots (wPP-CDs) and a solid residue, which was converted into carbonized biochar (wPP-BC). Blue-colored fluorescent wPP-CDs displayed excitation-dependent and pH-independent properties with a quantum yield (QY) of 8.82 %, which were exploited for the fluorescence sensing of p -NP with 4.20 μM limit of detection. Pyrolyzed biochar acting as an efficient catalyst effectively reduces p -NP to p -aminophenol (p -AP) in just 16 min with a 0.237 min−1 rate of conversion. Furthermore, the produced p -AP was converted into paracetamol, an analgesic and antipyretic drug, to achieve zero waste theory. Thus, this study provides the execution of sustainable approaches based on the integral valorization of biowaste that can be further recycled and reused, offering an effective way to attain a profitable circular economy. [Display omitted] • Value-added carbon nanomaterials were synthesized from waste pea peels. • Blue fluorescent carbon dots act as a fluorescent sensor for p -nitrophenol (p -NP). • Solid biochar serves as a promising catalyst for the efficient reduction of p -NP. • The obtained p -aminophenol was further converted into a valuable drug, paracetamol. [ABSTRACT FROM AUTHOR]

Acacia Senegal waste (ASW) is remaining biomass following gum Arabic harvesting and has no use mentioned in the literature as of yet. This study aims to convert ASW into valuable biochar via two comparative thermal and hydrothermal techniques, which include pyrochar ASW at 300 °C (PC ASW300) and hydrochar ASW at 180 °C (HC ASW180), respectively, for Cu (II) adsorption from aqueous solutions. SEM-EDS, FTIR, XRD, and XPS were used to characterize the biochar. Adsorption performance was studied as a function of pH, contact time, and adsorbent concentration. Adsorption kinetics were best fit for a pseudo-second-order model. And thermodynamics studies revealed that Cu (II) on biochar was endothermic, spontaneous, and best fitted to the Langmuir isotherm model. Pyrochar adsorption capacity (31.93 mg g−1) was seven times that of hydrochar (5.45 mg g−1). ASW treated with phosphorus (PC H 3 PO 4 and HC H 3 PO 4) prior to the carbonization altered the pore structure and surface functional groups as well (O–P–O, P–CH 3 , and P–OH) of biochar. It was found that treating with phosphorous acid increased adsorption capacity to 141.7 mg g−1 and 22.24 mg g−1 for PC H 3 PO 4 and HC H 3 PO 4 , respectively. The surface functional groups of biochar resulted from lignin, alkaloids, and polysaccharides combined with Cu (II) during the adsorption process via surface complexation accompanied by π-electron interaction and Cu (II) reduction. These findings shed light on the ASW biochar potential as a new green cost-effective adsorbent and drew an insightful understanding of Cu (II) adsorption performance and mechanism. It is concluded that ASW-derived biochar is highly effective and a promising alternative for Cu (II) decontamination from wastewater. [Display omitted] • Acacia Senegal waste biochar has a potential as Cu(II) cost-effective adsorbents. • Phosphorous activated biochar grew Cu(II) adsorption capacity up to five times. • Copper adsorption on surface of biochar was accompanied by Cu(II) reduction. • Surface complexation and π electron interaction played a key role on adsorption. • Pyrochar show greater adsorption capacity and removal efficiency than hydrochar. [ABSTRACT FROM AUTHOR]

This study investigated the catalytic activity of biochar materials derived from algal biomass Sargassum fusiforme (S. fusiforme) for groundwater remediation. A facile single-step pyrolysis process was used to prepare S. fusiforme biochar (SFBC X), where x denotes pyrolysis temperatures (600 °C-900 °C). The surface characterization revealed that SFBC 800 possesses intrinsic N and P heteroatoms. The optimum experimental condition for acetaminophen (AAP) degradation (>98.70%) was achieved in 60 min using 1.0 mM peroxymonosulfate (PMS), 100 mg L−1 SFBC 800 , and pH 5.8 (unadjusted). Moreover, the degradation rate constant (k) was evaluated by the pseudo-first-order kinetic model. The maximum degradation (>98.70%) of AAP was achieved within 60 min of oxidation. Subsequently, the k value was calculated to be 6.7 × 10−2 min−1. The scavenger tests showed that radical and nonradical processes are involved in the SFBC 800 /PMS system. Moreover, the formation of reactive oxygen species (ROS) in the SFBC 800 /PMS system was confirmed using electron spin resonance (ESR) spectroscopy. Intriguingly, both radical (O 2 •−, •OH, and SO 4 •−) and nonradical (1O 2) ROS were formed in the SFBC 800 /PMS system. In addition, electrochemical studies were conducted to verify the electron transfer process of the nonradical mechanism in the SFBC 800 /PMS system. The scavenger and electron spin resonance (ESR) spectroscopy showed that singlet oxygen (1O 2) is the predominant component in AAP degradation. Under optimal condition, the SFBC 800 /PMS system reached ∼81% mineralization of AAP within 5 min and continued to ∼85% achieved over 60 min of oxidation. Coexisting ions and different aqueous matrices were investigated to examine the feasibility of the catalyst system, and the SFBC 800 /PMS system was found to be effective in the remediation of AAP-contaminated groundwater, river water, and effluent water obtained from wastewater treatment plants. Moreover, the SFBC 800 -activated PMS system demonstrated reusability. Our findings indicate that the SFBC 800 catalyst has excellent catalytic activity for AAP degradation in aquatic environments. [Display omitted] • PMS-activated Sargassum fusiforme biochar (SFBC 800) boosts acetaminophen breakdown. • Inherent N and P in SFBC 800 enhance the AAP degradation pathway. • Singlet oxygen (1O 2) is the dominant component in the SFBC 800 /PMS system. • SFBC 800 demonstrated reusability in groundwater, surface water, and wastewater. [ABSTRACT FROM AUTHOR]

The co-transport behavior of environmental pollutants with biochar particles has aroused great interests from researchers due to the concerns about pollutant diffusion and environmental exposure after biochar is applied to soil. In this work, the recovery and co-transport behavior of biochar micron-/nano-particles (BCMP and BCNP) and lead (Pb2+) in saturated porous media were investigated under different ionic strength conditions (IS = 1, 5 and 10 mM) under a direct current electric field. The results showed that the electric field could significantly enhance the mobility of Pb adsorbed biochar particles, particularly BCNP. The recovery of Pb laden biochar particles was improved by 1.8 folds, reaching 78.8% at maximum under favorable condition at +0.5 V cm−1. According to the CDE (Convection-Dispersion-Equation) model and DLVO (Derjaguin-Landau-Verwey-Overbeek) theory analysis, the electric field facilitated the transport of Pb carried biochar mainly by increasing the negative charges on biochar surface and improving the repulsive force between biochar and porous media. High IS was favorable for biochar transport under the electric field, but inhibited desorbing Pb2+ from biochar (18% by maximum at IS = 10 mM). By switching the electric field power, a two-stage strategy was established to maximize the recovery of both biochar particles and Pb, where BCNP and Pb recovery were higher than electric field free case by 90% and 35%, respectively. The findings of this study can help build a biochar recovery approach to prevent potential risks from biochar application in heavy metal contaminated soil remediation. [Display omitted] • Electric field promoted the migration of both Pb laden/free biochar particles. • Up to 78.8% of Pb2+ laden biochar nano-particles recovered under 0.5 V·cm-1. • Electric field detach about 18% adsorbed Pb from biochar under high ionic strength. • Two-stage strategy were proposed to recover both biochar and Pb2+. [ABSTRACT FROM AUTHOR]

Biochar-based materials for air treatment have gained significant attention for removing health-detrimental volatile organic compounds (VOCs) and particulate matter (PM) in indoor air settings. However, high turnaround time, multiple pretreatment processes involved, and high pore size and low surface area (>10 μm, <100 m2 g−1) of lignocellulosic feedstocks demand alternative biochar feedstock material. Considering this, we designed a simple first-of-its-kind indoor air scrubbing material using diatoms-enriched microalgae biochar. In the present study, the microalgae were cultivated on waste anaerobic digestate (biogas slurry) and were pyrolyzed at three different temperatures: 300 °C (BC300), 500 °C (BC500), and 700 °C (BC700). The BC500 and BC700 showed the highest removal efficiencies (99 %) for total volatile organic carbons (TVOCs) and formaldehyde (HCHO) at concentrations of 1.22 mg m−3 HCHO and 8.57 mg m−3 TVOC compared to 50% efficiency obtained with commercially available surgical, cloth, and N95 masks. The biochar obtained showed a high Brunauer–Emmett–Teller (BET) surface area of 238 m2 g−1 (BC500) and 480 m2 g−1 (BC700) and an average pore size of 9–11 nm due to the mesoporous characteristic of diatom frustules. The comparatively poor performance of BC300 was due to lower surface area (150 m2 g−1) arising from incomplete organic removal, as evidenced by FESEM-EDX and FTIR. The high removal efficiencies in BC500 and BC700 were also attributed to the presence of reactive functional groups such as –OH and R–NH 2. Concurrently, the average particulate matter (PM10, PM2.5, and PM1) removal efficiency for BC500 and BC 700 ranged between 66 and 82.69 %. The PM removal performance of BC500 and BC700 was lower (15–20%) than commercially available masks. Overall, the present study highlights the importance of diatoms (reactive Si) present inside the pores of microalgal biochar for enhanced removal of PM, TVOCs, and HCHO at temperatures above 500 °C. This complete approach signifies a step towards establishing a self-sustainable and circular process characterized by minimal waste generation for indoor air treatment. [Display omitted] • Simultaneous removal of particulate matter PM10, PM2.5, PM1, TVOC's and HCHO. • Microalgal biochar contained 21.2 %w/w silica diatoms with pore size of 9–11 nm. • Diatoms increased specific surface area 2X (482 m2 g−1) than conventional biochars. • Developed material highly specific in removal of TVOC's and HCHO (∼99%). [ABSTRACT FROM AUTHOR]

Soil salinization is a major environmental hazard that limits land availability. Human-induced salt pollutants (HISPs) are regularly presented in large quantities on the contaminated site (such as brine leakages and salt-water spills), causing a devastating shock with high salt stress to the ecosystem. For instance, Saskatchewan resulted in a 48% drop in wheat production and a 0.3% decline in provincial GDP. As the calcium-modified biochar can potentially ameliorate the negative effects of HISPs on plants and improve the plant, phytoremediation with calcium-modified biochar can have increased detoxification of hazardous pollutants from sites. Therefore, the objective of our study was to develop a biochar-assisted phytoremediation employing diverse approaches to calcium modification for the sustainable removal of HISPs. The co-pyrolyzed calcium biochar achieved a remarkable removal rate of 18.06%, reducing salinity from 9.44 to 7.81 dS/m. During a 90-day long-term phytoremediation, the overall reduction rate of calcium-modified biochar stimulated the germination and growth of Thinopyrum ponticum. The result of post-treatment further indicated that co-pyrolyzed biochar with Ca transferred salt into the plant compared to Ca-coated biochar, which only immobilized HISPs on its surface. These results offer two different treatment approaches for diverse situations involving HISPs contamination, addressing current in-situ spills and providing a calcium-related biochar technology for further research in desalination. [Display omitted] • Ca-coated and Ca-copyrolyzed biochar for phytoremediation of saline soil were investigated. • Ca-modified biochars generated from copyrolysis and coating. • Ca-modified biochars displayed enhanced capability in direct removing salt from brine water • In a 90-day phytoremediation, Ca-modified biochar reduced salinity and improved soil quality • Ca-copyrolyzed and Ca-coated biochar have diverse roles in salt migration into vegetations [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are pervasive ecological pollutants produced essentially during the inadequate burning of organic materials. PAHs are a group of different organic compounds that are made out of various aromatic rings. PAHs pose a serious risk to humans and aquatic ecosystems because of their mutagenic and carcinogenic properties. In this way, there is a critical prerequisite to utilizing successful remediation strategies and methods to limit the dangerous effect of these pollutants on the ecosystem. Biochar has believed of intriguing properties such as simple manufacturing operations and more affordable and more productive materials. Biochar is a sustainable carbonaceous material that has an enormous surface area with bountiful functional groups and pore structure, which has huge potential for the remediation of toxic pollutants. This review emphasizes the occurrence, development, and fate of toxic PAHs in the environment. In the present review, the properties and role of biochar in the removal of PAHs were illustrated, and the influencing factors and an efficient key mechanism of biochar for the remediation of PAHs were discussed in detail. Various surface modification methods can be utilized to improve the biochar properties with the magnetization process; the advancements of modified biochar are pointed out in this review. Finally, the constraints and prospects for the large-scale application of biochar in the remediation of toxic pollutants are highlighted. [Display omitted] • Utilization of biochar as an effective strategy for PAH remediation has been reviewed. • Overview on Surface and functional properties of biochar used for PAH removal was emphasized. • Role and primary mechanisms of different biochar in PAH removal has been detailed in the review. • Modification for enhancement of biochar properties for effective removal of PAH was described. [ABSTRACT FROM AUTHOR]

Activated carbon (AC) has important industrial and environmental applications as it has excellent abilities to sorb contaminants such as per- and polyfluoroalkyl substances (PFAS). Current research aims to develop activated biochars (AB) from renewable biomass to replace AC that is produced from fossil feedstock. Both AC and AB are primarily comprised of condensed aromatic carbon (ConAC), the component that is the focus of this study. ConAC is characterized to determine its relationship with biochar activation conditions and PFAS sorption, which are understudied at present. Benzenepolycarboxylic acid (BPCA) markers for ConAC were quantified in steam-activated biochars (AB-Steam) and carbon dioxide-activated biochars (AB-CO 2) prepared from waste timber at different temperatures (800, 850, 900 °C) and molar ratios of feedstock-carbon:steam (0.50 – 1.25). A non-activated biochar was also included as a reference. ConAC relative to total organic carbon content was higher in AB-Steam than in AB-CO 2 (92 ± 2 % vs. 81 ± 11%). The ratio of benzenehexa- (B6CA) to benzenepentacarboxylic (B5CA) acids revealed that AB-Steam also had larger ConAC clusters than AB-CO 2. These findings provide novel evidence that steam activation is more effective than CO 2 activation in creating ConAC. To assess how ConAC impacts AB sorption abilities, AB-Steam were used to remediate PFAS from contaminated soils. The observed strong correlations between ConAC content and sorption of long-chain PFAS suggest the importance of hydrophobic interactions between PFAS tails and ConAC. Poor correlations for short-chain PFAS, on the other hand, indicated the existence of electrostatic repulsion interactions between PFAS head groups and ConAC. Collectively, these results explain the great ability of AB-Steam to sorb PFAS from contaminated soils (up to 100% remediation). More broadly, this work demonstrates that the BPCA method can be a valuable tool to assess the quality of biochars and other carbonaceous sorbents in relation to their production conditions or contaminant sorption abilities. [Display omitted] • Condensed aromatic carbon (ConAC) content was determined by benzenepolycarboxylic acid (BPCA) markers. • Steam-activated biochars had more ConAC (92 ± 2 %) of larger cluster size than CO 2 -activated biochars (81 ± 11%). • More PFAS sorption (71 ± 25%) was observed at higher ConAC content (> 92%). • Hydrophobic and electrostatic repulsion interactions likely exist between PFAS and ConAC. [ABSTRACT FROM AUTHOR]

The fertosphere, as the interfaces between fertilizer granular and soil particles, represents a key hotspot for nitrogen transformation processes, particularly for ammonia (NH 3) and nitrous oxide (N 2 O) emissions. Understanding the heterogeneity of the fertosphere, especially when incorporating organic amendments like biochars, is crucial for predicting NH 3 and N 2 O emissions after soil fertilization. In this study, we investigated the effects of three types of biochar (pristine, aged, and acid-washed biochar) on heterogeneity of fertosphere induced by localized urea application. pH-specific planar optodes were employed to visualize pH gradients in fertosphere hotspots with high spatial and temporal resolution. In addition, we conducted thorough measurements of the gradient distribution of electric conductivity (EC), mineral N, aqueous NH 3 in soil and enzyme activities relevant to nitrification. Concurrently, NH 3 and N 2 O emissions from the soil were continuously monitored at a high temporal resolution. Initially, urea-induced fertosphere exhibited significant NH 3 emissions, primarily attributed to the pH elevation resulting from urea hydrolysis. However, after 6 days, NH 3 emissions subsided, and there was a notable sharp increase in N 2 O emissions. Importantly, compared to urea application alone, the inclusion of pristine biochar led to a delay in soil pH decline with a 19% rise in NH 3 emission. Aged biochar, characterized by a higher content of oxygen functional groups, demonstrated increased NH 4 +/NH 3 adsorption capacity and enhanced ammonia monooxygenase (AMO) activity in soil, resulting in an 18% reduction in NH 3 emission. While a slight decrease of 5% in NH 3 cumulative emission was observed in the acid-washed biochar treatment. Notably, biochar could potentially promote nitrification-derived N 2 O emissions due to the accumulation of NH 3 oxidation products (NH 2 OH). These findings could contribute to refining N transformation models for fertilized soils, and optimizing N fertilizer application strategies. [Display omitted] • Localized urea application induced pH gradients along fertosphere up to 25 mm. • TAN and NO 3 −-N had opposite gradients across the fertosphere. • Biochar could attenuate the heterogeneity of fertosphere, but promote NH 3 emissions. • Increased AMO and decreased HAO nitrification enzyme activities raised N 2 O emission. [ABSTRACT FROM AUTHOR]

The application of carbon nanoparticles (CNPs) and biochar in agriculture for improving plant health and soil quality and alleviating metal stress offers alternative approaches to meet the ever-increasing demand for food. However, poor understanding of their roles in improving crop production under Cu stress represents a significant obstacle to their wide application in agriculture. To clarify how CNPs and biochar affect corn (Zea mays L.) seed germination, seedling growth, plant health, and nutrient uptake under different Cu stress levels, soil-less Petri-dish and greenhouse soil-based bioassays were conducted. The results revealed that CNPs and biochar stimulated corn seed germination and seedling growth. Besides, they were effective in immobilizing Cu2+ sorption in sandy soil and alleviating Cu stress for plant growth, as shown by the increased plant height and dry biomass. The plant nutrient uptake efficiency (NUE) was significantly increased by CNPs, with a maximum increase of 63.1% for N and 63.3% for K at the highest Cu2+ stress level (400 mg Cu2+ L−1). In contrast, non-significant effects on NUE were observed with biochar treatments regardless of Cu stress levels. Interestingly, CNPs significantly increased plant uptake of Cu in the Petri dish test, while biochar inhibited plant uptake of Cu under both experimental conditions. Principle component analysis (PCA) and Pearson correlation analysis indicated that CNPs mitigated Cu stress mainly by elevating antioxidant enzyme activities, enhancing plant photochemical efficiency, and increasing plant uptake of N and K, while biochar was more likely to reduce bioavailability and uptake of Cu in the plant. These findings have great implications for the application of CNPs and biochar as plant growth stimulators and de-toxicity agents in agriculture. [Display omitted] • CNPs and biochar improved seed germination and plant growth under Cu stress. • CNPs elevated antioxidant enzyme activities, enhanced plant photochemical efficiency and plant uptake of N and K. • Biochar reduced Cu concentration and decreased activities of antioxidant enzymes in plants. [ABSTRACT FROM AUTHOR]

This study evaluates pyrolysis products obtained from biomasses (silver grass, pine, and acacia) harvested from heavy-metal-contaminated soil. To do so, we utilized two methods: a batch one-stage pyrolysis, and a continuous two-stage pyrolysis. The study results show that the yields and characteristics of bio-oils and biochars varied depending on the pyrolysis process and the type of biomass. The two-stage pyrolysis having two reactors (auger and fluidized bed reactors) appeared to be very suitable for specific chemicals production such as acetic acid, acetol, catechol, and levoglucosan. The biochar obtained from the fluidized-bed reactor of two-stage pyrolysis had high thermal stability, high crystallinity, high inorganic content, and a small number of functional groups. In contrast, the biochar obtained from the one-stage pyrolysis had low thermal stability, low crystallinity, a high carbon content, and a large number of functional groups. The biochar obtained from the two-stage pyrolysis appeared to be suitable as a material for catalyst support and as an adsorbent. The biochar obtained from one-stage pyrolysis appeared to be a suitable as a soil amendment, as an adsorbent, and as a precursor of activated carbon. All biochars showed a negative carbon footprint. In the end, this study, which was conducted using two different processes, was able to obtain the fact that products of pyrolysis biomass contaminated with heavy metals have different characteristics depending on the process characteristics and that their utilization plans are different accordingly. If the optimal utilization method proposed through this study is found, pyrolysis will be able to gain importance as an effective treatment method for biomass contaminated with heavy metals. [Display omitted] • Results of one-stage and two-stage pyrolysis of contaminated biomass were compared. • Two-stage pyrolysis turned out to be suitable for specific chemicals production. • Biochar from fluidized-bed reactor has potential as catalyst support and absorbent. • Biochar from fixed-bed reactor has potential as soil amendment and absorbent. • All biochars seemed to be applicable in construction field as sustainable materials. [ABSTRACT FROM AUTHOR]

In this study, a novel Fe 3 O 4 -based biochar coupled surface-imprinted polymer was constructed via simple hydrothermal route for salicylic acid recognition and degradation in advanced oxidation processes. The material exhibited excellent adsorption capability, up to 118.23 mg g−1, and efficient degradation performance, 87.44% removal rate within 240 min, based on integrating the advantages of both huge specific surface area as well as abundant functional groups from biochars and specific recognition sites from imprinted cavities. Moreover, high selectivity coefficient (11.67) showed stable recognition in single and binary systems. SO 4 •− and •OH were confirmed as reactive oxygen species in catalytic reaction according to quenching experiments and EPR analysis. The degradation mechanism and pathway were unraveled by DFT calculations and LC-MS. Furthermore, the results of toxicity evaluation, stability and reusability demonstrated application potential in the field of water environment restoration. This study confirmed that molecular imprinting provided a promising solution to targeted removal of emerging environmental pollutants by degrading after the enrichment of pollutants to the composites surface. [Display omitted] • A novel molecularly imprinted polymers coated Fe 3 O 4 -BC was successfully synthesized. • Adsorption-degradation activities and specific recognition of SA by MI-FBC were improved. • MI-FBC exhibited good stability and regenerability with tolerance to wide pH and anions. • The mechanism and pathway of SA removal were proposed based on experiments and DFT calculations. [ABSTRACT FROM AUTHOR]

Removal of toxic dyes such as Rhodamine B is essential as it pollutes aqueous and soil streams as well. This comprehensive study explores the potential of Calophyllum inophyllum seed char as an efficient bio-adsorbent based on their characteristic properties and a comparative study between various carbon-based adsorbents on the adsorption capacity of Rhodamine B dye. In this study, the char was prepared from Calophyllum inophyllum seed using a slow pyrolysis process (298 K/min) at an optimum temperature of 823 K and used as an adsorbent for the removal of Rhodamine B from water. The resulting char was mesoporous and had 155.389 m2/g surface areas (BET) and 0.628 cc/g pore volume. The formation of pores was observed from the SEM analysis. The adsorption studies were tested and optimized through various parameters such as solution pH, adsorbent dosage, initial dye concentration, stirring speed, contact time, and solution temperature. Maximum 95.5 % removal of Rhodamine B was possible at the pH: 2, stirring speed: 100 rpm, time: 25 min, temperature 308 K, and dose: 1.2 g/L. The highest adsorption capacity at equilibrium was determined to be 169.5 (mg/g) through Langmuir adsorption isotherm studies and followed pseudo 2nd order kinetics. The thermodynamics study confirmed the adsorption processes were spontaneous (ΔG°=−0.735 kJ/mol) and endothermic (ΔH° = 4.1 kJ/mol) processes. The reusability study confirmed that the mesoporous char can be reused as an efficient adsorbent for up to 3 cycles for environmental remediation. [Display omitted] • Non-edible seed pyrolytic char is a good adsorbent for the removal of dye. • Seed char is a mesoporous and nano structured adsorbent. • Dye adsorption was high in acidic medium. • Possible to remove 95 % Rhodamine B dye at 1.2 g/L adsorbent dosage. • The biochar can be used up to three cycles and can be regenerated. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is classified as a heavy metal (HM) and is found into the environment through both natural processes and intensified anthropogenic activities such as industrial operations, mining, disposal of metal-laden waste like batteries, as well as sludge disposal, excessive fertilizer application, and Cd-related product usage. This rising Cd disposal into the environment carries substantial risks to the food chain and human well-being. Inadequate regulatory measures have led to Cd bio-accumulation in plants, which is increasing in an alarming rate and further jeopardizing higher trophic organisms, including humans. In response, an effective Cd decontamination strategy such as phytoremediation emerges as a potent solution, with innovations in nanotechnology like biochar (BC) and nanoparticles (NPs) further augmenting its effectiveness for Cd phytoremediation. BC, derived from biomass pyrolysis, and a variety of NPs, both natural and less toxic, actively engage in Cd removal during phytoremediation, mitigating plant toxicity and associated hazards. This review scrutinizes the application of BC and NPs in Cd phytoremediation, assessing their synergistic mechanism in influencing plant growth, genetic regulations, structural transformations, and phytohormone dynamics. Additionally, the review also underscores the adoption of this sustainable and environmentally friendly strategies for future research in employing BC-NP microaggregates to ameliorate Cd phytoremediation from soil, thereby curbing ecological damage due to Cd toxicity. [Display omitted] • Cd toxicity varies with factors such as metal form, pH, and exposure duration. • Address protocols, impacts, economics, and toxicity in Cd phytoremediation. • Phytoremediation economically mitigates HM pollution, preserving ecosystems. • BC enhances nutrient availability, microbial communities, and Cd adsorption. • BC and NPs synergistically reduce Cd toxicity, improving soil and plant health. [ABSTRACT FROM AUTHOR]

Production of medium-chain fatty acids (MCFAs) from sewage sludge has dual effects on valuable sludge disposal and renewable energy generation, while low efficiency limits its application. Biochar addition is considered an effective method to improve MCFAs production. In this study, the influence of biochar adding strategies (i.e., adding biochar in acidification or chain elongation (CE) processes) on MCFAs production was explored. Results showed that by adding biochar in the acidification process, MCFAs accumulation increased by over 114%, accompanied by the highest carbon conversion efficiency (134.66%) and electron transfer efficiency of MCFAs (94.22%) by the terminal CE. Adding biochar before the acidification process better enriched CE bacteria (e.g., Paraclostridium) and strengthened the dominant metabolic pathway. In contrast, the biochar added before the CE process priorly enriched the bacteria capable of degrading organics, like unclassified_f__Dysgonomonadaceae , norank_f__norank_o__OPB41 , and Acetobacterium. The differences in excessive ethanol oxidation and short-chain fatty acids accumulation induced by varied adding strategies might be responsible for this. [Display omitted] • Adding strategy influenced the bacteria and metabolic pathways in MCFA production. • Adding biochar in the acidification process benefited MCFAs accumulation. • Adding biochar in the CE process better enriched the acidification bacteria. • Microbial analysis clarified the key genus varied with different adding strategies. [ABSTRACT FROM AUTHOR]

Robust membrane modifiers were achieved for the first time by functionalizing the algal biochar of unique porous structure. The biochar was prepared through the pyrolysis of Cladophora glomerata , the most widespread freshwater macroalga, functionalized by diethylenetriamine and dendrimer poly(amidoamine), and employed to fabricate positively charged composite nanofiltration membranes. The presence of hydrophilic functionalizers of positive charge on the membrane was verified through Fourier transform infrared and energy dispersive X-ray analyses and atomic force microscopy and zeta potential measurements were performed to determine surface roughness and confirm positive charge of the modified membranes. Dispersion of modifiers on the surface and morphology of the were also revealed through field-emission scanning electron microscopy images. It has shown that, compared to the pristine membrane, pure water fluxes were increased by 214% and 185%, and water contact angles were reduced from 66.1° to 39.5° and 43.3° in those modified by biochar functionalized with dendrimer poly(amidoamine) and diethylenetriamine, respectively. More than 90% dye rejections and salt and heavy metals removals were recorded for the membranes possessed 0.6 wt% of modifiers. Finally, a comparative study conducted between the novel modifier introduced in this study and those reported in the literature, indicated that C. glomerata biochar decorated with amine functional groups could be considered as a robust and practical alternative to the common modifiers used to manipulate nanocomposite membranes characteristics. [Display omitted] • Novel modifier introduced from the most widespread macroalga of environmental issue. • C. glomerata biochar is functionalized with amine groups to possess positive charge. • Introduced biochar can be a robust alternative to typical membrane modifiers. • Flux and filtration performance improved in positively charged modified membranes. • Advanced heavy metal rejection achieved by incorporation of functionalized modifier. [ABSTRACT FROM AUTHOR]

Thermo-chemical behavior of a microalgal biomass; Dunaliella salina was investigated through thermo-gravimetric analyses. Fully-grown D. salina biomass were subjected for biochar conversion using pyrolytic treatment at three distinct heating rates such as 2.5, 5, and 15 °C min−1. The kinetic appraisals were explained by using model-free kinetics viz., Kissinger-Akahira-Sanose, Flynn-Waal-Ozawa and Starink iso-conversional correlations with concomitant evaluation of activation energies (E a). The Ea value is 194.2 kJ mol−1 at 90% conversion in FWO model, which is higher as compared to other two models. Moisture, volatile substances, and other biochemical components of the biomass were volatilized between 400 and 1000 K in two separate thermo-chemical breakdown regimes. Microscopic and surface characterization analyses were carried out to elucidate the elemental and morphological characteristics of the biomass and biochar. Further, the proficiency of the prepared biochar was tested for removing naphthalene from the watery media. The novelty of the present study lies in extending the applicability of biochar prepared from D. salina for the removal of a model polyaromatic hydrocarbon, naphthalene. [Display omitted] • Prepared microalgal biochar exhibited superior naphthalene sorption from aqueous media. • Utilized Freundlich isotherm and pseudo-second order kinetics to elucidate sorption. • D. salina -derived biochar's surface complexation facilitated naphthalene sorption. • Prepared biochar combines microalgal biomass valorization with pollution reduction. [ABSTRACT FROM AUTHOR]

Cr(VI) contamination is widely recognized as one of the major environmental hazards. To address the problem of remediation of soil Cr(VI) contamination and utilization of waste peanut shells, this study comprehensively investigated the effects of peanut shell-derived biochar loaded with root exudates of hyperaccumulator Leersia hexandra Swartz on Cr(VI) reduction and microbial community succession in soil. This study confirmed that root exudate-loaded peanut shell biochar reduced soil pH while simultaneously increasing DOC, sulfide, and Fe(II) concentrations, thereby facilitating the reduction of Cr(VI), achieving a reduction efficiency of 81.8%. Based on XPS and SEM elemental mapping analyses, Cr(VI) reduction occurred concurrently with the Fe and S redox cycles. Furthermore, the microbial diversity, abundance of the functional genera (Geobacter , Arthrobacter , and Desulfococcus) and the metabolic functions associated with Cr(VI) reduction were enhanced by root exudate-loaded biochar. Root exudate-loaded biochar can promote both direct Cr(VI) reduction mediated by the Cr(VI)-reducing bacteria Arthrobacter , and indirect Cr(VI) reduction through Cr/S/Fe co-transformation mediated by the sulfate-reducing bacteria Desulfococcus and Fe(III)-reducing bacteria Geobacter. This study demonstrates the effectiveness of peanut shell biochar loaded with root exudates of hyperaccumulator Leersia hexandra Swartz to promote soil Cr(VI) reduction, reveals the mechanism how root exudate-loaded biochar shapes functional microbial communities to facilitate Cr(VI) reduction, and proposes a viable strategy for Cr(VI) remediation and utilization of peanut shell. [Display omitted] • Peanut shell biochar loaded with root exudates of L. hexandra facilitated Cr(VI) reduction. • Root exudate-loaded biochar enhanced Cr(VI) reduction by shaping microbial communities. • Cr(VI) reduction occurred concurrently with Fe and S redox cycles. • Root exudate-loaded biochar promoted indirect Cr(VI) reduction through Cr/S/Fe co-transformation. • Geobacter , Arthrobacter , and Desulfococcus are involved in Cr(VI) reduction. [ABSTRACT FROM AUTHOR]

As a cost-effective material, biochar, known as 'black gold', has been widely used for environmental applications (EA), including chromium-contaminated wastewater remediation. However, limited reports focused on the multiple impacts of biochar, including energy consumption (EC) and environmental risk (ER). Hence, to recommend biochar as a green material for sustainable development, the three critical units were explored and quantitatively assessed based on an adapted 3E model (EA-EC-ER). The tested biochar was produced by limited-oxygen pyrolysis at 400–700 °C by using three typical biomasses (Ulva prolifera , phoenix tree, and municipal sludge), and the optimal operational modulus of the 3E model was identified using six key indicators. The findings revealed a significant positive correlation between EC and biochar yield (p < 0.05). The biochar produced by phoenix tree consumed more energy due to having higher content of unstable carbon fractions. Further, high-temperature and low-temperature biochar demonstrated different chromium removal mechanisms. Notably, the biochar produced at low temperature (400 °C) achieved better EA due to having high removal capacity and stability. Regarding ER, pyrolysis temperature of 500 °C could effectively stabilize the ecological risk in all biochar and the biochar produced by Ulva prolifera depicted the greatest reduction (37-fold). However, the increase in pyrolysis temperature would lead to an increase in global warming potential by nearly 22 times. Finally, the 3E model disclosed that the biochar produced by Ulva prolifera at 500 °C with low EC, high EA, and low ER had the most positive recommendation index (+78%). Importantly, a rapid assessment methodology was established by extracting parameters from the correlation. Based on this methodology, about eight percent of biochar can be the highest recommended from more than 100 collected peer-related data. Overall, the obtained findings highlighted that the multiple impacts of biochar should be considered to efficiently advance global sustainable development goals. [Display omitted] • An adapted 3E model assessed three critical units of typical biochar. • Yield is a key factor in the energy consumption of biochar. • Biochar produced at low temperatures has a greater Cr removal performance. • Ulva prolifera biochar has the maximum recommendation index. • A rapid assessment methodology was established by extracting parameters. [ABSTRACT FROM AUTHOR]

For environmental sustainability and to achieve sustainable development goals (SDGs), drinking water treatment must be done at a reasonable cost with minimal environmental impact. Therefore, treating contaminated drinking water requires materials and approaches that are inexpensive, produced locally, and effortlessly. Hence, locally available materials and their derivatives, such as biochar (BC) and activated carbon (AC) were investigated thoroughly. Several researchers and their findings show that the application of locally accessible materials and their derivatives are capable of the adsorptive removal of organic and inorganic contaminants from drinking water. The application of locally available materials such as lignocellulosic materials/waste and its thermo-chemically derived products, including BC and AC were found effective in the treatment of contaminated drinking water. Thus, this review aims to thoroughly examine the latest developments in the use of locally accessible feedstocks for tailoring BC and AC, as well as their features and applications in the treatment of drinking water. We attempted to explain facts related to the potential mechanisms of BC and AC, such as complexation, co-precipitation, electrostatic interaction, and ion exchange to treat water, thereby achieving a risk-free remediation approach to polluted water. Additionally, this research offers guidance on creating efficient household treatment units based on the health risks associated with customized adsorbents and cost-benefit analyses. Lastly, this review work discusses the current obstacles for using locally accessible materials and their thermo-chemically produced by-products to purify drinking water, as well as the necessity for technological interventions. [Display omitted] • Local materials and its derivatives in treatment of water has been discussed. • Properties of BC and AC derived from locally available materials were elaborated. • Mechanism in removal of organic and inorganic pollutants were discussed. • Development of BC and AC based household treatment units were deliberated. • Economy of BC and AC based water treatment units were elaborated. [ABSTRACT FROM AUTHOR]

The growing global population has led to a heightened need for food production, and this rise in agricultural activity is closely tied to the application of phosphorus-based fertilizers, which contributes to the depletion of rock phosphate (RP) reserves. Considering the limited P reserves, different approaches were conducted previously for P removal from waste streams, while the adsorption of ions is a novel strategy with more applicability. In this study, a comprehensive method was employed to recover phosphorus from wastewater by utilizing biochar engineered with minerals such as calcium, magnesium, and iron. Elemental analysis of the wastewater following a batch experiment indicated the efficiency of the engineered biochar as an adsorbent. Subsequently, the phosphorus-enriched biochar, hereinafter (PL-BCsb), obtained from the wastewater, underwent further analysis through FTIR, XRD, and nutritional assessments. The results revealed that the PL-BCsb contained four times higher (1.82%) P contents which further reused as a fertilizer supplementation for Brassica napus L growth. PL-BCsb showed citric acid (34.03%), Olsen solution (10.99%), and water soluble (1.74%) P desorption. Additionally, phosphorous solubilizing bacteria (PSB) were incorporated with PL-BCsb along two P fertilizer levels P45 (45 kg ha−1) and P90 (90 kg ha−1) for evaluation of phosphorus reuse efficiency. Integrated application of PL-BCsb with half of the suggested amount of P45 (45 kg ha−1) and PSB increased growth, production, physiological, biochemical, and nutritional qualities of canola by almost two folds when compared to control. Similarly, it also improved soil microbial biomass carbon up to four times, alkaline and acid phosphatases activities both by one and half times respectively as compared to control P (0). Furthermore, this investigation demonstrated that waste-to-fertilizer technology enhanced the phosphorus fertilizer use efficiency by 55–60% while reducing phosphorus losses into water streams by 90%. These results have significant implications for reducing eutrophication, making it a promising approach for mitigating environmental pollution and addressing climate change. [Display omitted] • Sugarcane bagasse biochar was produced and engineered with Ca, Mg and Fe. • Phosphorus (P) adsorption was performed from eutrophic wastewater. • P laden biochar (PL-BCsb) harvested by P precipitation with Ca+2, Mg+2, and Fe+3. • P adsorption was accomplished and confirmed by FTIR and XRD analyses. • PL-BCsb was evaluated as fertilizer to canola growth and development in pot study. [ABSTRACT FROM AUTHOR]

The UV/sulfite-based advanced reduction process (ARP) emerges as an effective strategy to combat per- and polyfluoroalkyl substances (PFAS) pollution in water. Yet, the UV/sulfite-ARP typically operates at highly alkaline conditions (e.g., pH > 9 or even higher) since the generated reductive radicals for PFAS degradation can be quickly sequestered by protons (H+). To overcome the associated challenges, we prototyped a biochar-surfactant-system (BSS) to synergistically enhance PFAS sorption and degradation by UV/sulfite-ARP. The degradation and defluorination efficiencies of perfluorooctanoic acid (PFOA) depended on solution pH, and concentrations of surfactant (cetyltrimethylammonium bromide; CTAB), sulfite, and biochar. At high pH (8–10), adding biochar and BSS showed no or even small inhibitory effect on PFOA degradation, since the degradation efficiencies were already high enough that cannot be differentiated. However, at acidic and neutral pH (6–7), an evident enhancement of PFOA degradation and defluorination efficiencies occurred. This is due to the synergies between biochar and CTAB that create favorable microenvironments for enhanced PFOA sorption and deeper destruction by prolonging the longevity of reductive radicals (e.g., SO 3 •−), which is less affected by ambient pH conditions. The performance of UV/sulfite/BSS was further optimized and used for the degradation of four PFAS. At the optimal experimental condition, the UV/sulfite/BSS system can completely degrade PFOA with >30% defluorination efficiency for up to five continuous cycles (n = 5). Overall, our BSS provides a cost-effective and sustainable technique to effectively degrade PFAS in water under environmentally relevant pH conditions. The BSS-enabled ARP technique can be easily tied into PFAS treatment train technology (e.g., advanced oxidation process) for more efficient and deeper defluorination of various PFAS in water. [Display omitted] • Biochar-surfactant-system (BSS) was prototyped for PFAS sorption and destruction. • BSS enhanced sorption and destruction of various PFAS at neutral pH. • Efficient defluorination of PFOA was achieved for five continuous cycles. • BSS-enabled advanced reduction process is promising for PFAS remediation. [ABSTRACT FROM AUTHOR]

The intensive accumulation of di-2-ethylhexyl phthalate (DEHP) in agricultural soils has resulted in severe environmental pollution that endangers ecosystem and human health. Biochar is an eco-friendly material that can help in accelerating organic pollutant degradation; nevertheless, its roles in enhancing DEHP removal in rhizosphere remain unclear. This work investigated the impacts of biochar dosage (0%–2.0%) on DEHP degradation performance in tomato rhizosphere by comprehensively exploring the change in DEHP metabolites, bacterial communities and DEHP-degrading genes. Our results showed a significant increase of rhizosphere pH, organic matter and humus by biochar amendment, which achieved a satisfactorily higher DEHP removal efficiency, maximally 77.53% in treatments with 1.0% of biochar. Biochar addition also remarkably changed rhizosphere bacterial communities by enriching some potential DEHP degraders of Nocardioides , Sphingomonas , Bradyrhizobium and Rhodanobacter. The abundance of genes encoding key enzymes (hydrolase, esterase and cytochrome P450) and DEHP-degrading genes (pht3 , pht4 , pht5 , benC-xylZ and benD-xylL) were increased after biochar amendment, leading to the change in DEHP degradation metabolism, primarily from benzoic acid pathway to protocatechuic acid pathway. Our findings evidenced that biochar amendment could accelerate DEHP degradation by altering rhizosphere soil physicochemical variables, bacterial community composition and metabolic genes, providing clues for the mechanisms of biochar-assisted DEHP degradation in organic contaminated farmland soils. [Display omitted] • The accelerated DEHP degradation in the tomato rhizosphere amended with biochar can be explained by the higher pH and humus levels. • Biochar amendment changed DEHP degradation pathways from benzoic acid to protocatechuic acid. • More genes encoding DEHP-degrading enzymes in biochar treatments. [ABSTRACT FROM AUTHOR]

Groundwater pollution caused by the leakage of petroleum and various fuel oils is becoming a serious environmental problem. In this study, carbon-based materials including biochar and hydrochar were applied to investigate the effects of additives on the toluene removal in the extracted groundwater under microaerobic condition with the addition of nitrate. Biochar and hydrochar could adsorb toluene, and thus enhance the toluene removal in the system. The toluene removal efficiency was 8.2–8.9 mg/(g·h) at the beginning, and then decreased with time in the control and the hydrochar treatment, while it remained the stable values in the biochar treatment, owing to the fact that biochar could reduce the NO 3 −-N loss by partial denitrification. Moreover, biochar could prompt the growth of toluene-degrading bacteria including Thauera , Rhodococcus, Ideonella and Denitratisoma, which had the capability of denitrification. However, hydrochar could stimulated the growth of denitrifiers without toluene-degrading capacity including Candidatus Competibacter and Ferrovibrio , which might play a key role in the partial denitrification of the system. The findings are helpful for developing remediation techniques of contaminated groundwater. [Display omitted] • Biochar and hydrochar can adsorb toluene and enhance toluene removal. • Biochar can reduce the NO 3 −-N loss by the partial denitrification. • Biochar can prompt the growth of toluene-degrading bacteria. • Low NO 3 −-N concentrations can reduce toluene-degrading capacity. [ABSTRACT FROM AUTHOR]

Contamination by potentially toxic metals and metalloids (PTMs) has become a significant health and environmental issue worldwide. Sorption has emerged as one of the most prominent strategies for remediating both soil and water contamination. New sorbents are being developed to provide economically viable and environmentally sound alternatives, in alignment with the principles of the Sustainable Development Goals. This research aimed to assess the potential effects on human health and environmental toxicity following the sorption of cadmium (Cd), lead (Pb), and zinc (Zn) using peat, compost, and biochar as sorbents. The peat was collected in Brazil, a country with a tropical climate, while the compost and biochar were produced from the organic fraction of municipal solid waste (OFMSW). In terms of bioaccessibility, the results showed the following order: compost < biochar < peat for Pb, and compost < peat < biochar for Cd and Zn. There was a significant growth inhibition for Eruca sativa and Zea mays exposed to increasing concentrations of PTMs treated with peat and compost. The presence of contaminants played a decisive role on immobilization of neonates of Ceriodaphnia silvestrii after treatments with compost and, especially, peat. However, the biochar addition rate caused a significant influence on the outcomes of ecotoxicity across all tested species. Although the samples treated with biochar exhibited lower residual concentrations of PTMs than those treated with compost and peat, the inherent toxicity of biochar might be attributed to the material itself. The exposure to residual PTM concentrations post-desorption caused ecotoxic effects on tested species, emphasizing the need to assess PTM desorption potential. Peat, compost, and biochar are promising alternatives for the sorption of PTMs, but the addition rates must be properly adjusted to avoid the occurrence of undesirable ecotoxicological effects. This research offers valuable insights for sustainable environmental management and protection by thoroughly investigating the impacts of different sorbents and contaminants on aquatic and terrestrial ecosystems. [Display omitted] • Pb had lowest bioaccessibility among tested metals when pre-sorbed onto the compost. • The sensitivity order was established as: root length > shoot length > germination. • Eruca sativa displayed higher phytotoxicity compared to Zea mays. • Biochar revealed inherent aquatic ecotoxicity in Ceriodaphnia silvestrii. • The toxicity of peat and compost samples originated from the presence of PTMs. [ABSTRACT FROM AUTHOR]

While numerous studies have addressed the photocatalytic degradation of 2,6-dichlorophenol (2,6-DCP) in wastewater, an existing research gap pertains to operational factors' optimization by non-linear prediction models to ensure a cost-effective and sustainable process. Herein, we focus on optimizing the photocatalytic degradation of 2,6-DCP using artificial intelligence modeling, aiming at minimizing initial capital outlay and ongoing operational expenses. Hence, Fe/Zn@biochar, a novel material, was synthesized, characterized, and applied to harness the dual capabilities of 2,6-DCP adsorption and degradation. Fe/Zn@biochar exhibited an adsorption energy of −21.858 kJ/mol, effectively capturing the 2,6-DCP molecules. This catalyst accumulated photo-excited electrons, which, upon interaction with adsorbed oxygen and/or dissolved oxygen generated •O 2 −. The •OH radicals could also be produced from h+ in the Fe/Zn@biochar valence band, cleaving the C–Cl bonds to Cl− ions, dechlorinated byproducts, and phenols. An artificial neural network (ANN) model, with a 4-10-1 topology, " trainlm " training function, and feed-forward back-propagation algorithm, was developed to predict the 2,6-DCP removal efficiency. The ANN prediction accuracy was expressed as R2 = 0.967 and mean squared error = 5.56e–22. The ANN-based optimized condition depicted that over 90% of 2,6-DCP could be eliminated under C 0 = 130 mg/L, pH = 2.74, and catalyst dosage = 168 mg/L within ∼4 h. This optimum condition corresponded to a total cost of $7.70/m3, which was cheaper than the price estimated from the unoptimized photocatalytic system by 16%. Hence, the proposed ANN could be employed to enhance the 2,6-DCP photocatalytic degradation process with reduced operational expenses, providing practical and cost-effective solutions for petrochemical wastewater treatment. [Display omitted] • Fe/Zn@biochar was synthesized for 2,6-dichlorophenol photocatalytic degradation. • Adsorption energy of Fe/Zn@biochar (−22 kJ/mol) was utilized for 2,6-DCP removal. • ANN model was developed to optimize factors affecting 2,6-DCP photodegradation. • Over 90% of 2,6-DCP could be eliminated at initial concentration of 130 mg/L. • Application of ANN (4-10-1) model reduced photocatalytic treatment cost by 15.6%. [ABSTRACT FROM AUTHOR]

Biochar has been extensively studied in wastewater treatment systems. However, the role of biochar in the single-stage partial nitritation anammox (SPNA) system remains not fully understood. This study explored the impact of biochar on the SPNA at ambient temperatures (20 °C and 15 °C). The nitrogen removal rate of the system raised from 0.43 to 0.50 g N/(L·d) as the biochar addition was raised from 2 to 4 g/L. Metagenomic analysis revealed that gene abundances of amino sugar metabolism and nucleotide sugar metabolism, amino acid metabolism, and quorum sensing were decreased after the addition of biochar. However, the gene abundance of enzymes synthesizing NADH and trehalose increased, indicating that biochar could stimulate electron transfer reactions in microbial metabolism and assist microorganisms in maintaining a steady state at lower temperatures. The findings of this study provide valuable insights into the mechanism behind the improved nitrogen removal facilitated by biochar in the single-stage partial nitritation anammox system. [Display omitted] • Biochar improved the nitrogen removal performance of the SPNA system at 20 °C. • Biochar enhanced the activity of enzyme in AnAOB, while inhibited the production of extracellular polymeric substance. • Biochar promoted genes of production of trehalose. [ABSTRACT FROM AUTHOR]

This study assessed the impact of different plant-derived biochar (cornstalk, rice husk, and sawdust) on bacterial community and functions for compost maturity and gaseous emissions during the composting of food waste. Results showed that all biochar strengthened organic biotransformation and caused a higher germination index on day 12 (over 100%), especially for rice husk biochar to enhance the growth of Thermobifida related to aerobic chemoheterotrophy. Rice husk biochar also achieved a relatively higher reduction efficiency of methane (85.8%) and ammonia (82.7%) emissions since its greater porous structure. Besides, the growth of Pseudomonas , Pusillimonas , and Desulfitibacter was restricted to constrict nitrate reduction, nitrite respiration, and sulfate respiration by optimized temperature and air permeability, thus reducing nitrous oxide and hydrogen sulfide emissions by 48.0–57.3% by biochar addition. Therefore, rice husk biochar experienced the optimal potential for maturity increment and gaseous emissions mitigation. [Display omitted] • Biochar achieved compost maturity of food waste in 12 days (GI ≥ 100%). • Biochar limited the growth of Pseudomonas , Pusillimonas , and Desulfitibacter. • Biochar decreased CH 4 , N 2 O, NH 3 , and H 2 S emissions by 48.0–93.6%. • Rice husk biochar favored Thermobifida growth to enhance aerobic chemoheterotrophy. • Rice husk biochar was more beneficial to advance maturity and gaseous reduction. [ABSTRACT FROM AUTHOR]

Biochar (BC) has a strong potential for activating arsenic (As) in soil; thus, the phytoremediation efficiency of As-polluted soils is enhanced with Pteris vittata L. A pot experiment was conducted to investigate the potential of BC to assist in phytoremediation with P. vittata. The effects of BC on physicochemical properties, available As, enzyme activities, and the bacterial community in the rhizosphere soil were investigated, and the biomass, physiology, and As uptake of P. vittata were analyzed. The results indicated that applying BC facilitated available As in the P. vittata rhizosphere soil , and the phytoremediation efficiency percentage increased in the As-polluted soils, such as 3.80% and 8.01% under the 2% and 5% BC treatments compared to the control, respectively. Phytoremediation with P. vittata and BC significantly improved soil organic matter content, available N, P, and K, enzyme activities, and the bacterial community. BC promoted Streptomyces (26.6-54.2%) and Sphingomonas (12.3-30.8%) abundance which regulated the growth and As uptake by P. vittata. Moreover, applying BC increased the biomass, and As uptake by P. vittata. Overall, BC strengthened the phytoremediation of As-polluted soils by improving soil pH, nutrient concentrations, enzyme activities, bacterial community structure, and soil arsenic activation, growth, and absorption by P. vittata. [Display omitted] • Biochar changes the composition of bacterial communities. • As fraction was changed by biochar and thus increasing available As. • Biochar increased the biomass, As uptake and arsenic removal of P. vittata L. [ABSTRACT FROM AUTHOR]

Microplastics (MPs), as emerging pollutants, have attracted the attention of environmentalists, statespersons, and the scientific community over the last few decades. To address the spread of MPs in the environment, it is imperative to develop various removal techniques and materials that are effective, scalable, and ecologically benign. However, to the best of our knowledge, no review has systematically examined the removal of MPs using adsorption or provided an in-depth discussion on various adsorbents. Adsorption is an inexpensive and effective technology for wastewater treatment. Recently, many researchers have conducted studies on MP remediation using diverse adsorbent materials, such as biochar, activated carbon, sponges, carbon nanotubes, metal-layered oxides, metal-organic frameworks (MOFs), and zeolites. Each adsorbent has advantages and disadvantages. To overcome their disadvantages, researchers have been designing and developing hybrid adsorbents for MP remediation. This review provides insights into these individual adsorbents and also discusses hybrid adsorbents for MP removal. Finally, the review elaborates on future possibilities and ways to enable more efficient, scalable, and environmentally friendly MP cleanup. Overall, this review bridges the gap between contemporary MP remediation using adsorption techniques and adsorbent development. [Display omitted] • Adsorption-based microplastic remediation was reviewed. • The factors affecting microplastic adsorption were thoroughly discussed. • A comprehensive analysis is presented on several microplastic adsorbents. • Microplastic adsorption challenges and future perspectives are examined. [ABSTRACT FROM AUTHOR]

Due to the rapid development of human beings, heavy metals are occurred in the Yunnan-Guizhou Plateau and Panxi Plateau, the special dry and hot climate areas. Pb and Cu can be quickly transferred through water-plant-animal, further harm to human health by food chain. Therefore, the study of heavy metal treatment is imminent. In this study, Biochar-montmorillonite composites were prepared by co-pyrolysis and characterized, and their ability to remove lead and copper from water-soil process were tracked. And their effectiveness in remediating soil contaminated by lead and copper was documented. The composite material has the rich pore structure, large specific surface area (81.5 m2/g) and a variety of surface functional groups such as C–C, C O, ester-metal and metal-oxygen bonds. Pb and Cu can be effectively adsorbed and fixed to the level of no harm to human health. The adsorption reaction of lead and copper on the Biochar-montmorillonite composites is more suitable to be described by Langmuir adsorption and pseudo-second-order kinetics models. The saturation adsorption capacity of the composite for Pb was measured as 212.5 mg/g. For Cu, it was 136.5 mg/g. The data were fitted by a two-compartment first-order kinetic model. f fast for Pb and Cu is estimated to be 0.81 and 0.78, respective. Fast adsorption is dominant and belongs to typical chemical adsorption, which is consistent with the second-order kinetic results. With 5 % of the composite, approximately 80 % of exchangeable heavy metals in those soils collected from the Yunnan-Guizhou Plateau and Panxi Plateau were reduced. The biochar-montmorillonite composites made Pb and Cu change to stable residual state, up to 35 %. Besides, it effectively restored the activity of urease and sucrase in soils. Results indicated that biochar-montmorillonite composites can be effectively used as an environment-friendly adsorbent or passivator to purify heavy metals in soils. [Display omitted] • Combining agroforestry wastes with natural clay minerals to prepare composites. • The material has rich pore structure and large specific BET surface area. • The novel-materials have shown excellent sorption capacity for Pb and Cu, and can reach the equilibrium quickly. • The composite material can effectively reduce exchangeable heavy metals and is suitable for different soil properties. [ABSTRACT FROM AUTHOR]

The world's attention is drawn to the widespread ingestion, toxicity, and bioaccumulation of the Atrazine (AT) and Endosulfan (ES). Pesticides have been proven to have endocrine-disrupting, genotoxic, and persistent characteristics. In this work, the structural design of green synthesized NiFe 2 O 4 is incorporated in rice husk biochar to form BC@NiFe 2 O 4 nanocomposite. Powder X-ray diffraction and microscopic analysis confirmed the semi-crystalline nature of BC@NiFe 2 O 4 reduced due to the incorporation of amorphous BC. The green BC@NiFe 2 O 4 nanocomposite degraded AT and ES up to 98 % and 92 %, respectively. The maximum degradation achieved by BC@NiFe 2 O 4 nanocomposite with minimum pollutants concentration (50 mg L−1) with 10 mg catalyst dose at acidic pH in natural sunlight because of the higher negative value of zeta potential (−26.4 mV) and lower band gap (2.5 eV). The degradation process involves first-order kinetics followed by initial Langmuir adsorption. The presence of various radical quenchers (t-BuOH, p -BZQ, Na 2 EDTA) has led to the conclusion that hydroxyl radicals play a significant role in the degradation of the toxic substances AT and ES. Additionally, a green-fabricated BC@NiFe 2 O 4 nanocomposite has exhibited exceptional efficiency in degrading AT and ES pollutants in actual wastewater samples. Furthermore, this nanocomposite has demonstrated outstanding sustainability and cost-effectiveness, maintaining its effectiveness for up to eight cycles without a noticeable reduction in activity. In summary, due to its favorable surface characteristics, the environmentally friendly BC@NiFe 2 O 4 nanocomposite holds excellent promise as a unique and potential photocatalyst for various industrial applications. [Display omitted] • Facile, cost-effective and green approach for synthesis of BC@NiFe 2 O 4 nanocomposite. • Removal of AT and ES pesticides followed first order kinetics. • BC@NiFe 2 O 4 degraded pesticides AT (98 %), ES (92 %) from agriculture wastewater. • Excellent reusability up to 8th cycles ensures it stability and sustainability. [ABSTRACT FROM AUTHOR]

Supplementation of conductive materials has been proved to be a promising approach for enhancing microbial interspecies electron transfer (IET) in anaerobic digestion systems. In this study, magnetic bamboo-based biochar was prepared at temperatures of 400–800 °C via a ball milling/carbonization method, and it immobilized in mature anaerobic granular sludge (AGS) aimed to enhance methane production by improving the IET process between syntrophic microbial communities in the AGS. Results showed that the AGS with magnetic biochar immobilization demonstrated increased glucotrophic and acetotrophic methane production by 69.54–77.56 % and 39.96–54.92 %, respectively. Magnetic biochar prepared at 800 °C with a relatively higher Fe content (0.37 g/g magnetic biochar) displayed a stronger electron charge/discharge capacity (36.66 F/g), and its immobilization into AGS promoted methane production most. The conductivity of AGS increased by 52.13–87.32 % after incorporating magnetic biochar. Furthermore, the extracellular polymeric substance (EPS) of AGS showed an increased capacitance and decreased electron transfer resistance possibly due to the binding of magnetic biochar and more riboflavin secretion in EPS, which could contribute to the accelerated IET process in the inner AGS. In addition, the immobilization of magnetic biochar could promote the production of volatile fatty acids by 15.36–22.50 %. All these improvements may jointly lead to the enhanced methane production capacity of AGS. This study provided a fundamental understanding of the role of incorporated magnetic biochar in AGS in promoting anaerobic digestion performance. [Display omitted] • Magnetic biochar immobilization enhanced acidogenesis and methanogenesis of AGS. • Magnetic biochar prepared at 800 °C had the highest promotion of CH 4 production. • Magnetic biochar prepared at 800 °C showed superior electron exchange capacity. • Magnetic biochar immobilization increased EPS capacitance and decreased resistance. [ABSTRACT FROM AUTHOR]

Synergizing photocatalytic reactions with machine learning methods can effectively optimize and automate the remediation of pollutants. In this work, commercial Degussa TiO 2 nanoparticles and lignin based biochar (LB) where used to prepare TiO 2 : lignin based biochar (TLB) composites using ultrasound-assisted co-precipitation method. The photocatalytic property of the TLB composites where studied by conducting the photocatalytic degradation of a Basic blue 41 (BB41) dye. The influence of calcination temperature, T:LB compositions, catalyst dosage, initial dye pH, initial dye concentration, and illumination time on photocatalytic dye degradation were experimentally studied. The degradation efficiency of 96.72 % was obtained under optimized conditions for the photocatalyst calcined at 500 °C containing a 1:1 wt percentage of TiO 2 and LB. The experimental data was further used to predict the photocatalytic degradation efficiency using Gradient Tree Boosting (GTB) and Extra Trees (ET) models. The GTB model gave the highest prediction accuracy of 94 %. The permutation variable importance revealed catalyst dosage and dye concentration as the most influential parameters in the prediction of the photocatalytic dye degradation efficiency. [Display omitted] • Photocatalyst using lignin based biochar was prepared. • The photocatalytic studies for BB41 dye degradation was carried out. • The dye degradation study was modeled using GTB and ET model. • The GTB model was selected as the optimum prediction model. • Catalyst dosage and dye concentration were declared as crucial parameters. [ABSTRACT FROM AUTHOR]

Manipulating the methanotroph (MOB) composition and microbial diversity is a promising strategy to optimize the methane (CH 4) biofiltration efficiency of an engineered landfill cover soil (LCS) system. Inoculating soil with exogenous MOB-rich bacteria and amending soil with biochar show strong manipulating potential, but how the two stimuli interactively shape the microbial community structure and diversity has not been clarified. Therefore, three types of soils with active CH 4 activities, including paddy soil, river wetland soil, and LCS were selected for enriching MOB-dominated communities (abbreviated as B_PS, B_RWS, and B_LCS, respectively). They were then inoculated to LCS which was amended with two distinct biochar. Besides the aerobic CH 4 oxidation efficiencies, the evolution of the three microbial communities during the MOB enrichment processes and their colonization in two-biochar amended LCS were obtained. During the MOB enriching, a lag phase in CH 4 consumption was observed merely for B_LCS. Type II MOB Methylocystis was the primary MOB for both B_PS and B_LCS; while type I MOB dominated for B_RWS and the major species were altered by gas concentrations. Compared to biochar, a more critical role was demonstrated for the bacteria inoculation in determining the community diversity and function of LCS. Instead, biochar modified the community structures by mainly stimulating the dominant MOB but could induce stochastic processes in community assembly, possibly related to its inorganic nutrients. Particularly, combined with biochar advantages, the paddy soil-derived bacteria consortiums with diverse MOB species demonstrated the potent adaption to LCS niches, not only retaining the high CH 4 -oxidizing capacities but also shaping a community structure with more diverse soil function. The results provided new insights into the optimization of an engineered CH 4 -mitigation soil system by manipulating the soil microbiomes with the cooperation of exogenous bacteria and biochar. [Display omitted] • Exogenous MOB-rich bacteria dominate the microbial community assembly of LCS. • B_PS endows LCS with active CH 4 oxidation and more diverse soil function. • Biochar modifies microbial community structure by stimulating the dominant MOB. • Biochar could induce stochastic assembly of bacteria when B_PS was inoculated. [ABSTRACT FROM AUTHOR]

Hierarchically porous magnetic biochar (HMB) had been found to act as an effective amendment to remediate cadmium (Cd) in water and soil in a previous study, but the effects on wheat growth, Cd uptake and translocation mechanisms, and soil microorganisms were unknown. Therefore, soil Cd form transformation, soil enzyme activity, soil microbial diversity, wheat Cd uptake and migration, and wheat growth were explored by adding different amounts of HMB to alkaline Cd-contaminated soil under pot experiments. The results showed that application of HMB (0.5 %–2.0 %) raised soil pH, electrical conductivity (EC) and available Fe concentration, decreased soil available Cd concentration (35.11 %–50.91 %), and promoted Cd conversion to less bioavailable Cd forms. HMB treatments could reduce Cd enrichment in wheat, inhibit Cd migration from root to stem, rachis to glume, glume to grain, and promote Cd migration from stem to leaf and stem to rachis. HMB (0.5 %–1.0 %) boosted antioxidant enzyme activity, reduced oxidative stress, and enhanced photosynthesis in wheat seedlings. Application of 1.0 % HMB increased wheat grain biomass by 40.32 %. Besides, the addition of HMB (0.5 %–1.0 %) could reduce soil Cd bioavailability, increase soil enzyme activity, and increase the abundance and diversity of soil bacteria. Higher soil EC brought forth by HMB (2.0 %) made the wheat plants and soil bacteria poisonous. This study suggests that applying the right amount of HMB to alkaline Cd-contaminated soil could be a potential remediation strategy to decrease Cd in plants' edible parts and enhance soil quality. [Display omitted] • HMB facilitated the rapid conversion of Cd in soil to less bioavailable Cd forms. • HMB could promote Cd migration from stem to leaf and stem to rachis. • HMB could effectively reduce Cd uptake and translocation to wheat grains. • Moderate HMB could positively affect bacterial species diversity and abundance. • Moderate HMB could alleviate the wheat Cd-induced oxidative damage. [ABSTRACT FROM AUTHOR]

Anthracene belongs to the polycyclic aromatic hydrocarbon (PAH) consisting of benzene rings, unusually highly stable through more π-electrons and localized π-bond in entire rings. Aqueous-phase anthracene adsorption using carbon-based materials such as biochar is ineffective. In this paper, carbon dots (CDs) derived from the acid treatment of coconut shell biochar (CDs/MCSB) decorated with chitosan (CS) are successfully synthesized and applied for anthracene removal from aqueous solutions. The h -CDs/MCSB exhibited fast adsorption of anthracene with significant sorption capacity (Q max = 49.26 mg g−1) with 95 % removal efficiency at 60 min. The study suggested chemisorption dominated monolayer anthracene adsorption onto h -CDs/MCSB, where a significant role was played by ion-exchange. Density Functional Theory (DFT) suggested the anthracene adsorption was dominated by the electrostatic interactions and delocalized electron, induced by higher polarizability of functional groups on the surface of hybrid CDs/MCSB assisted by chitosan (h -CDs/MCSB). In addition, the aromatic structure of CDs/MCSB and high polarizability of functional groups provided the strong interactions between benzene rings of anthracene and hybrid adsorbent-assisted multiple π-bond through delocalized π-bond and polarization-induced H-bond interactions. The presence of carboxylic and sulfonic groups on the CDs/MCSB surface also contributed to the effective adsorption of anthracene was confirmed by the fluorescence spectra. The results showed that the hybrid adsorbent was an effective material for removing PAHs, usually difficult to remove from water owing to the presence of benzene rings in their structures. Further, consistency in the DFT results suggested the outstanding binding capacity with the anthracene molecules with h -CDs/MCSB. [Display omitted] • Enhanced anthracene adsorption using carbon dots decorated chitosan (CDs/MCSB). • CDs/MCSB showed highly polarized functional groups and delocalized surface energy. • Consistency of the DFT study revealed significant removal efficiency for PAHs. [ABSTRACT FROM AUTHOR]

Extensive use of oxytetracycline (OTC) and the generation of its corresponding resistance genes have resulted in serious environmental problems. Physical-biological combined remediation is an attractive method for OTC degradation because of its high remediation efficiency, stability, and environmental friendliness. In this study, an effective OTC-degrading strain identified as Pseudomonas aeruginos a OTC-T, was isolated from chicken manure. In the degradation experiment, the degradation rates of OTC in the degradation systems with and without the biochar addition were 92.71–100 % and 69.11–99.59 %, respectively. Biochar improved the tolerance of the strain to extreme environments, and the OTC degradation rate increased by 20.25 %, 18.61 %, and 13.13 % under extreme pH, temperature, and substrate concentration conditions, respectively. Additionally, the degradation kinetics showed that biochar increased the reaction rate constant in the degradation system and shortened the degradation period. In the biological toxicity assessment, biochar increased the proportion of live cells by 17.63 % and decreased the proportion of apoptotic cells by 58.87 %. Metabolomics revealed that biochar had a significant effect on the metabolism of the strains and promoted cell growth and reproduction, effectively reducing oxidative stress induced by OTC. This study elucidates how biochar affects OTC biodegradation and provides insights into the future application of biochar-assisted microbial technology in environmental remediation. [Display omitted] • The isolated strain possessed high degradation efficiency to oxytetracycline. • Biochar increased the biodegradation rate of oxytetracycline by 13.13–20.25 %. • Biochar reduced the biotoxicity of the degradation system. • Biochar increased the antioxidant capacity of the strain. [ABSTRACT FROM AUTHOR]

A large amount of manure is generated from concentrated animal feeding operations (CAFOs), leading to serious environmental issues and hazardous risks from pathogens, such as methicillin-resistant Staphylococcus aureus. Therefore, developing an effective method for manure disposal is essential. Thus, in this study, we suggest the use of CO 2 in pyrolysis of hen manure (HM) as an effective method to convert the carbon in HM into syngas (especially carbon monoxide (CO)). HM was used and tested as the model compound. From the results of thermo-gravimetric analysis, the decarboxylation of CaCO 3 in HM in the presence of N 2 was realized at temperatures ranging from 638 to 754 °C. The Boudouard reaction was observed at ≥ 664 °C in the presence of CO 2. Despite the lack of occurrence of the Boudouard reaction, more CO formation was observed in the presence of CO 2 at ≥ 460 °C. This was deemed as a homogeneous reaction induced by CO 2. Considering the high Ca content of HM, HM biochar in N 2 and CO 2 were used as adsorbent for removal of Cadmium (Cd), which is toxic heavy metal. The adsorption capacities of HM_N 2 and HM_CO 2 were 302.4 and 95.7 mg g−1, respectively. The superior performance of HM_N 2 is mainly attributed to the presence of Ca(OH) 2 , which provides favorable (alkaline) conditions for precipitation and ion exchange. Our results indicate the environmental benefits from using CO 2. Specifically, CO 2 (representative greenhouse gas) converted into fuel. Given this, pyrolysis of HM in the presence of CO 2 was achieved at ≤ 640 °C, and the atmospheric condition should be switched from CO 2 to N 2 at ≥ 640 °C to ensure the decarboxylation of CaCO 3. [Display omitted] • Thermochemical conversion of hen manure (HM) was attempted using N 2 and CO 2. • The formation of CO under CO 2 conditions was enhanced compared to that of N 2. • Because HM biochar contained high Ca, the biochar was used to adsorb cadmium. • Pyrolysis of HM in CO 2 is preferable at ≤ 660 °C and should be switched from CO 2 to N 2 at ≥ 660 °C. [ABSTRACT FROM AUTHOR]

Water crisis around the world leads to a growing interest in emerging contaminants (ECs) that can affect human health and the environment. Research showed that thousands of compounds from domestic consumers, such as endocrine disrupting chemicals (EDCs), personal care products (PCPs), and pharmaceuticals active compounds (PhAcs), could be found in wastewater in concentration mostly from ng L−1 to μg L−1. However, generally, wastewater treatment plants (WWTPs) are not designed to remove these ECs from wastewater to their discharge levels. Scientists are looking for economically feasible biotreatment options enabling the complete removal of ECs before discharge. Microalgae cultivation in domestic wastewater is likely a feasible approach for removing emerging contaminants and simultaneously removing any residual organic nutrients. Microalgal growth rate and contaminants removal efficiency could be affected by various factors, including light intensity, CO 2 addition, presence of different nutrients, etc., and these parameters could greatly help make microalgae treatment more efficient. Furthermore, the algal biomass harvests could be repurposed to produce various bulk chemicals such as sustainable aviation fuel, biofuel, bioplastic, and biochar; this could significantly enhance the economic viability. Therefore, this review summarizes the microalgae-based bioprocess and their mechanisms for removing different ECs from different wastewaters and highlights the different strategies to improve the ECs removal efficiency. Furthermore, this review shows the role of different ECs in biomass profile and the relevance of using ECs-treated microalgae biomass to produce green products, as well as highlights the challenges and future research recommendations. [Display omitted] • Microalgal-based emerging contaminants removal is prospective and sustainable approach. • Optimization of different process parameters could improve ECs removal efficiencies. • ECs containing biomass could be a potential feedstock for production of bioproducts. • Microalgal-based treatment could be an economically relevant plan for domestic WWTP. [ABSTRACT FROM AUTHOR]

This study investigates our hypothesis that how effect of arsenic stress on okra (Abelmoschus esculentus L.) can be alleviated through the use of waste materials such as steel slag (SS) and corncob biochar (BC). Different growth variables, biochemical parameters, oxidative stress markers, enzymatic and non-enzymatic antioxidants and glyoxylase enzyme activities were assessed. When okra was exposed to As, there was a noticeable decrease in seedling length, biomass, relative water content, various biochemical attributes, however, electrolyte leakage and lipid peroxidation in okra were enhanced. The supplementation of SS and BC—either individually or in combination—improved the growth parameters and reduced oxidative stress markers. Application of SS and BC also lowered As accumulation in roots and shoots of okra mitigating adverse effects of As exposure. Additionally, the activities of antioxidant and glyoxalase enzyme increased when SS and BC were present, concurrently reducing methylglyoxal content. Arsenic-induced stress led to oxidative damage, an enhancement in both enzymatic and non-enzymatic antioxidants, induced the synthesis of thiol and phytochelatins in roots and shoots. These may play a vital function in alleviating oxidative stress induced by As. Superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase activities were significantly enhanced in As-treated plants. These enhancement were further amplified when SS and BC were amended to As-treated okra. Therefore, synergistic application of SS and BC effectively protects okra against oxidative stress induced by As by increasing both antioxidant defense and glyoxalase systems. Both SS, an industrial byproduct, and BC, generated from agricultural waste, are cost-effective, environmentally friendly, safe, and non-toxic materials which can be used for crop production in As contaminated soil. [Display omitted] • Steel slag and corncob biochar enhanced growth of okra plants under arsenic stress. • ROS scavenging mechanism was strengthened by osmolytes accumulation. • Total acid soluble thiol and phytochelatin contents were enhanced in okra roots and shoots under arsenic stress. • Steel slag and corncob biochar declined arsenic-incited oxidative damage by boosting antioxidant and glyoxalase system. [ABSTRACT FROM AUTHOR]

The olive stone is a large waste product of the olive oil extraction industry. The present study investigates developing activated carbon from olive stone waste (OSAC) to remove pharmaceuticals from water. Different temperatures and olive stone: KOH ratios were studied. The OSAC produced at 750 °C and 1:3 ratio was found to have the highest porosity and surface area and was tested in the adsorption process. Diclofenac and ciprofloxacin were selected as model contaminants. The adsorption process was optimized with regards to OSAC dosage, pH, temperature, and initial concentration of adsorbate. The OSAC was found to be effective for a wide pH range (2–11) with an optimum dosage of 1 g/L at 25 °C. The pharmaceuticals were almost completely removed in 75 min. The adsorption was endothermic and followed first-order kinetics with physical mechanisms such as electrostatic possibly being the main driver. The optimum conditions were applied to test the removal of diclofenac and ciprofloxacin in synthetic water, lake water (Lake Balaton, Hungary) and secondary wastewater for seven cycles. There was little difference between the removal of the tested water matrices highlighting the potency of OSAC as an adsorbent for pharmaceutical removal in industrial applications. The removal dropped from >99% for the first cycle to 20–30% for the seventh cycle. [Display omitted] • Both diclofenac and ciprofloxacin were removed from different water matrices. • The long-term performance of derived fossil-free carbon was up to 7 cycles. • Optimum removal conditions were pH 7, 25 °C, 50 mg/L mixture and OSAC of 1.0 g/L. • Fast removal of the pollutant's mixture within olive stones waste by 75 min. [ABSTRACT FROM AUTHOR]

Biochar as an effective adsorbent can be used for the removal of triclocarban from wastewater. Biochar-derived dissolved organic carbon (BC-DOC) is an important carbonaceous component of biochar, nonetheless, its role in the interaction between biochar and triclocarban remains little known. Hence, in this study, sixteen biochars derived from pine sawdust and corn straw with different physico-chemical properties were produced in nitrogen-flow and air-limited atmospheres at 300–750 °C, and investigated the effect of BC-DOC on the interaction between biochar and triclocarban. Biochar of 600∼750 °C with low polarity, high aromaticity, and high porosity presented an adsorption effect on triclocarban owing to less BC-DOC release as well as the strong π-π, hydrophobic, and pore filling interactions between biochar and triclocarban. In contrast and intriguingly, biochar of 300∼450 °C with low aromaticity and high polarity exhibited a significant solubilization effect rather than adsorption effect on triclocarban in aqueous solution. The maximum solubilization content of triclocarban in biochar-added solution reached approximately 3 times its solubility in biochar-free solution. This is mainly because the solubilization effect of BC-DOC surpassed the adsorption effect of biochar though the BC-DOC only accounted for 0.01–1.5 % of bulk biochar mass. Furthermore, the high solubilization content of triclocarban induced by biochar was dependent on the properties of BC-DOC as well as the increasing BC-DOC content. BC-DOC with higher aromaticity, larger molecular size, higher polarity, and more humic-like matters had a greater promoting effect on the water-solubility of triclocarban. This study highlights that biochar may promote the solubility of some organic pollutants (e.g., triclocarban) in aqueous environment and enhance their potential risk. [Display omitted] • Biochar of 300∼450 °C improved the solubility of triclocarban, • Biochar of 600∼750 °C presented an adsorption effect on triclocarban, • Solubilization effect of biochar depended on the content and properties of BC-DOC, • Biochar might enhance the mobility and the potential risk of triclocarban. [ABSTRACT FROM AUTHOR]

It remains a significant challenge to develop a kind of cost-effective and eco-friendly adsorbent with strong immobilization capabilities for ammonium in farmland. In this work, we employed Ca/Al layered double hydroxide-supported carbon dots (CDs@Ca/Al-LDHs) as a novel and efficient adsorbent for ammonium immobilization both in aqueous and soil environments. Such a composite could exhibit a high adsorption capacity towards ammonium in solution, which was four times higher than zeolite and three times higher than biochar under the same conditions. The mechanism investigations revealed that electrostatic interactions between the negatively charged CDs and the positively charged ammonium played a key role in the adsorption. In 30-day leaching experiments, the fabricated composite cumulatively reduced ammonium and nitrate by 6.3% and 9.7%, respectively at a dosage of 0.1% (w/w). Incubation experiments further confirmed that the developed composite could effectively inhibit ammonia volatilization and nitrification by immobilizing the ammonium within soil matrices. Our results demonstrated that CDs@Ca/Al-LDHs represented a promising candidate for cost-effective and eco-friendly immobilization of excess ammonium from over-fertilized farmland. [Display omitted] • Synthesized Ca/Al layered double hydroxide-supported carbon dots (CDs@Ca/Al-LDHs). • CDs@Ca/Al-LDHs exhibited a negative charge under neutral pH conditions. • Electrostatic interaction occurred between ammonium and CDs@Ca/Al-LDHs. • The adsorption capacity for ammonium was 4–5 times that of biochar and zeolite. • Leaching ammonium and nitrate was reduced by 6.3% and 9.7% at a dosage of 0.1%. [ABSTRACT FROM AUTHOR]

In recent times, microplastics have become a disturbance to both aquatic and terrestrial ecosystems and the ingestion of these particles can have severe consequences for wildlife, aquatic organisms, and even humans. In this study, two types of biochars were manufactured through the carbonization of naturally found starfish (SF-1) and aloevera (AL-1). The produced biochars were utilized as sensing electrode materials for the electrochemical detection of ∼100 nm polystyrene microplastics (PS). SF-1 and AL-1 based biochars were thoroughly analyzed in terms of morphology, structure, and composition. The detection of microplastics over biochar based electrodes was carried out by electrochemical studies. From electrochemical results, SF-1 based electrode exhibited the detection efficiency of ∼0.2562 μA/μM∙cm2 with detection limit of ∼0.44 nM whereas, a high detection efficiency of ∼3.263 μA/μM∙cm2 was shown by AL-1 based electrode and detection limit of ∼0.52 nM for PS (100 nm) microplastics. Process contributed to enhancing the sensitivity of AL-1 based electrode might associate to the presence of metal-carbon framework over biochar's surfaces. The AL-1 biochar electrode demonstrated excellent repeatability and detection stability for PS microplastics, suggesting the promising potential of AL-1 biochar for electrochemical microplastics detection. [Display omitted] • Biochars are produced by the carbonization of naturally found starfish (SF-1) and aloevera (AL-1). • Manufactured biochars utilize as sensing electrode materials for the electrochemical detection of PS (100 nm) microplastics. • A high detection efficiency of ∼3.263 μA/μM∙cm2 is recorded by AL-1 based electrode for PS (100 nm) microplastics. • AL-1 biochar electrode demonstrates excellent repeatability and detection stability for PS microplastics. [ABSTRACT FROM AUTHOR]