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The Chinese medicine residue (CMR) is composed of wet woody waste, including licorice and ephedra, so using hydrothermal carbonization (HTC) to recover renewable energy from the CMR is a suitable treatment method. An in-depth analysis of the physicochemical properties and structural evolution mechanism of hydrochars is helpful in fundamentally promoting the energy utilization of traditional Chinese medicine waste residue. Therefore, this study analyzed the physicochemical properties and morphological structure of hydrochar produced under varying HTC conditions using multiple testing methods. The evolution of the hydrochar's structural characteristics can be categorized into three stages: component decomposition, structural rearrangement, and carbonization. During the component decomposition and carbonization stages, numerous nanoscale micropores form within the hydrochar. These micropores' specific surface area and pore volume can reach up to 113.420 m 2 /g and 0.01913 cm 3 /g, respectively. The highest fractal dimension values for D1 and D2 are 2.6354 and 2.5565, while the maximum values for the microcrystalline stacking height (L c ) and the average number of crystalline layers (N ave ) are 0.3354 and 1.9968, respectively. Consequently, the hydrochar produced during these stages exhibits a rougher pore surface and a more complex structure, making it more suitable for adsorbing heavy metals from soil and sequestering CO 2 . During the structural rearrangement stage, the hydrochar exhibits higher contents of fixed carbon (FC), MgO, P 2 O 5 , and a higher C/N atomic ratio, with maximum values of 38.51%, 0.99%, 1.12%, and 28.49, respectively. Thus, the hydrochar produced during this stage is more suitable for soil remediation and nutrient recovery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study explored the innovative application of wood bottom ash (WBA) as an adsorbent for arsenic (As) removal from wastewater, focusing on the adsorption mechanism and optimisation of the operational conditions. Comprehensive spectroscopic analyses, including FE-SEM/EDS, BET, XRF, XRD, FT-IR, and XPS, were performed to examine the elemental and mineralogical changes in WBA before and after As adsorption. The study assessed the adsorption kinetics and isotherms, revealing that As adsorption reached equilibrium within 48 h, with a maximum capacity of 121.13 mg/g. The adsorption process followed a pseudo-second-order kinetic model and aligned well with the Langmuir isotherm, indicating that the process is governed by chemisorption and occurs as monolayer adsorption. The primary removal mechanism was the surface precipitation of amorphous calcium arsenate. Response surface methodology was employed to analyse and optimise the factors influencing As removal, including solution pH, ionic strength, adsorbent dose and reaction time. The optimal conditions for maximum As removal were pH 7.11, 8.37 mM ionic strength, 9.08 g/L WBA dose, and 2.58 h reaction time. This study offers novel insights into the efficient and cost-effective use of WBA for As removal, highlighting its potential as a sustainable solution for wastewater treatment in developing countries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The prevalent presence of pharmaceuticals in aquatic ecosystems underscores the necessity for developing cost-effective techniques to remove them from water. The utilization of affordable precursors in producing activated carbon, capable of rivaling commercial alternatives, remains a persistent challenge. The adsorption of diclofenac and ciprofloxacin onto a novel pinewood-derived activated carbon (FPWAC) was explored, employing a sequential activation process involving ammonium nitrate (NH 4 NO 3 ) treatment followed by sodium hydroxide (NaOH) activation. The produced FPWAC was then thoroughly characterized by employing several techniques. The removal of diclofenac and ciprofloxacin in water and real wastewater effluent was examined in batch tests. The optimum removal conditions were an FPWAC dosage of 1 g L -1 , pH 6, mixture concentration of 25 mg L -1 , and a temperature of 25 °C. The FPWAC was able to remove both pharmaceuticals for up to six cycles, with more than 95% removal for water and 90% for wastewater in the first cycle. The adsorption performance fitted well with the non-linear Freundlich isotherm for both pollutants. The kinetics of adsorption of diclofenac followed a pseudo-first-order model, while ciprofloxacin showed adherence to the pseudo-second-order model. FPWAC proved its potency as a low-cost adsorbent for pharmaceutical removal from wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Feedstock characteristics impact biochar physicochemical properties, and reproducible biochar properties are essential for any potential application. However, in most articles, feedstock aspects (i.e., taxonomic name of the species, part of the plant, and phenological phase) are scarcely reported. This research aimed at studying the effect of species and phenological stage of the feedstock on the properties of the derived biochars and, thus, adsorption capacities in water treatment. In this study, we analysed the anatomical characteristics of three different woody bamboo species [Guadua chacoensis (GC), Phyllostachys aurea (PA), and Bambusa tuldoides (BT)] in culms harvested at two different phenological phases (young and mature), and statistically correlated them with the characteristics of the six derived biochars, including their adsorption performance in aqueous media. Sclerenchyma fibres and parenchyma cells diameter and cell-wall width significantly differed among species. Additionally, sclerenchyma fibres and parenchyma cell-wall width as well as sclerenchyma fibre cell diameters are dependent on the phenological phase of the culms. Consequently, differences in biochar characteristics (i.e., yield and average pore diameter) were also observed, leading to differential methylene blue (MB) adsorption capacities between individuals at different phenological phases. MB adsorption capacities were higher for biochar produced from young culms compared to those obtained from matures ones (i.e., GC: 628.66 vs. 507.79; BT: 537.45 vs. 477.53; PA: 477.52 vs. 462.82 mg/g), which had smaller cell wall widths leading to a lower percentage of biochar yield. The feedstock anatomical properties determined biochar characteristics which modulated adsorption capacities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The utilization of agricultural and forestry residues for the development and preparation of green binderless fiberboard (BF) is an effective way to realize high-value utilization of lignocellulose biomass resources. This study focuses on the fabrication of BF with excellent mechanical and waterproof properties, utilizing poplar wood residue (PWR) as raw material and Trametes hirsuta as a pretreatment method. During the fermentation process, lignin-degrading enzymes and biological factors, such as sugars, were produced by T. hirsuta, which activated lignin by depolymerizing lignin bonds and modifying structural functional groups, and forming new covalent bonds between poplar fibers, ultimately enhancing adhesion. Additionally, the activated lignin molecules and sugar molecules coalesce under high temperatures and pressures, forming a dense carbonization layer that bolsters the mechanical properties of the fiberboard and effectively shields it from rapid water infiltration. The bio-pretreated BF for 10 days shows a MOR and MOE of up to 36.1 Mpa and 3704.3 Mpa, respectively, which is 261% and 247.8% higher than that of the bio-untreated fiberboard, and the water swelling ratio (WSR) rate is only 5.6%. Chemical composition analysis revealed that repolymerization occurred among lignin, cellulose, and hemicellulose, especially the molecular weight of lignin changed significantly, with the Mw of lignin increasing from 312066 g/mol to 892362 g/mol, and then decreasing to 825021 g/mol. Mn increased from 277790 g/mol to 316987.5 g/mol and then decreased to 283299.5 g/mol at 21 days. Compared to other artificial fiberboards prepared through microbial pretreatment, the BF prepared by microorganisms in this study exhibited the highest mechanical properties among the poplar wood biobased panels., Competing Interests: Declaration of competing interest All authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Recent research has found biochar to be a cost-effective adsorbent for removal of perfluoroalkyl substances in water. To promote cleaner production and sustainable waste management, this study explored the potential to produce activated biochars by co-pyrolyzing sawdust with iron-rich biosolids and polyaluminum sludge. The maximum capacity to adsorb perfluorooctanesulfonic acid (PFOS) reached 27.2 mg g -1 with biosolids-activated biochar and 19.2 mg g -1 with aluminum sludge-activated biochar, compared to 6.2 mg g -1 with sawdust biochar. The increased adsorption capacities were attributed to electrostatic interactions between the anionic PFOS and metal functionalities on the biochar surface. In contrast, hydrophobic interaction was the dominant adsorption mechanism of sawdust biochar. The presence of dissolved organic matter at 5-50 mg L -1 was found to inhibit adsorption of PFOS in water, while pH as low as 3.0 and sodium chloride concentrations up to 100 mM enhanced removal of PFOS by all the three adsorbents. In batch adsorption tests at environmentally relevant PFOS dosages and adsorbent dosage of 0.25 g L -1 , the biosolids-sawdust biochar and Al sludge-sawdust biochar removed 71.4% and 66.9% of PFOS from drinking water and 77.9% and 87.9% of PFOS from filtrate of sludge digestate, respectively. The biosolids-sawdust biochar additionally removed Fe, although the Al sludge-sawdust biochar released Al into the alkaline drinking water and filtrate. Overall, this study proved co-pyrolyzing sawdust and Fe-rich biosolids to be an effective approach to activate sawdust biochar for enhanced removal of PFOS while recycling wastewater treatment residuals and sawdust., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Soil cracking can significantly alter the water and nutrient migration pathways in the soil, influencing plant growth and development. While biochar usage has effectively addressed soil cracking, the feasibility of using less energy-intensive hydrochars in desiccating soils remains unexplored. This study investigates the impact of wood and peanut shell hydrochars on the desiccation cracking characteristics of clayey soil. A series of controlled environmental laboratory incubations with regular imaging was conducted to determine crack development's dynamic in unamended and hydrochar-amended soils. The results reveal that the addition of wood hydrochar at 2% and 4% dosage reduced the crack intensity factor (CIF) by 22% and 43%, respectively, compared to the unamended control soil. Similarly, the inclusion of peanut shell hydrochar at 2% and 4% lowered the CIF by 22% and 51%, respectively. The presence of hydrophilic groups on the surface of hydrochars, such as O-H, CH, and C-O-C, enhanced the water retention capacity, as confirmed by Fourier-transform infrared analysis. The CIF decrease is attributed to mitigated water evaporation rates, enabled by enhanced water retention within the hydrochar pore spaces. These findings are supported by scanning electron microscopy analyses of the hydrochar morphology. Despite CIF reduction with hydrochar incorporation, the crack length density (CLD) increased across all hydrochar-amended series. In contrast to unamended soil which exhibited pronounced widening of large cracks and extensive inter-pore voids, the incorporation of hydrochar resulted in higher CLD due to the formation of finer interconnecting crack meshes. Consequently, the unamended control soil suffered greater water loss due to heightened evaporation rates. This study sheds new light on the potential of hydrochars in addressing desiccation-induced soil cracking and its implications for water conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Biomass burning is a significant source of particulate matter (PM) in ambient air and its accurate source apportionment is a major concern for air quality. The discrimination between residential wood heating (RWH) and garden green waste burning (GWB) particulate matter (PM) is rarely achieved. The objective of this work was to evaluate the potential of non-targeted screening (NTS) analyses using HRMS (high resolution mass spectrometry) data to reveal discriminating potential molecular markers of both sources. Two residential wood combustion appliances (wood log stove and fireplace) were tested under different output conditions and wood moisture content. GWB experiments were carried out using two burning materials (fallen leaves and hedge trimming). PM samples were characterized using NTS approaches with both LC- and GC-HRMS (liquid and gas chromatography-HRMS). The analytical procedures were optimized to detect as many species as possible. Chemical fingerprints obtained were compared combining several multivariate statistical analyses (PCA, HCA and PLS-DA). Results showed a strong impact of the fuel nature and the combustion quality on the chemical fingerprints. 31 and 4 possible markers were discovered as characteristic of GWB and RWH, respectively. Complementary work was attempted to identify potential molecular formulas of the different potential marker candidates. The combination of HRMS NTS chemical characterization with multivariate statistical analyses shows promise for uncovering organic aerosol fingerprinting and discovering potential PM source markers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The application of commercial membranes is limited by the secondary pollution such as the usage of toxic chemicals for the membrane preparation and the disposal of aged membranes. Therefore, the green and environmentally friendly membranes are extremely promising for the sustainable development of membrane filtration in water treatment. In this study, the comparison of wood membrane with the pore size of tens microns (μm) and polymer membrane with the pore size of 0.45 μm was made to study the heavy metals removal in drinking water treatment by gravity-driven membrane (GDM) filtration system, and there was an improvement in the removal of Fe, Cu and Mn by wood membrane. The sponge-like structure of fouling layer for wood membrane made the retention time of heavy metals prolonged in contrast to the cobweb-like structure of polymer membrane. The carboxylic group (-COOH) content of fouling layer for wood membrane was greater than that for polymer membrane. Additionally, the population abundance of heavy metal-capturing microbes on the surface of wood membrane was higher compared with polymer membrane. The wood membrane provides a promising route to producing facile, biodegradable and sustainable membrane as a green alternative to polymer membranes in heavy metal removal from drinking water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Various construction materials and interior equipment contain volatile organic compounds (VOCs). Their higher quantities in indoor air are linked to poor health consequences and are controversial regarding health risks, given that people spend so much time indoors. As a result, VOCs in indoor air cause concern regarding sick building syndrome. From a historical perspective, wood and wood-based panels have been frequently employed. Nonetheless, wood appears to be a product and a material of the future in today's world. The emission of VOCs from wood and wood products is essential when assessing the impact of different materials on the indoor environment. The emission rate is affected by both the wood species and the boundary circumstances (drying, storage, etc.). The issue of VOCs emitted from wood, and wood-based panels are addressed in this review paper. The most prevalent VOCs were listed. The advantages and limits of using VOCs for analytical determination from these composites are discussed. [Display omitted] • VOC emissions from wood-based materials are measured qualitatively and quantitatively on a large scale. • Evaluation of volatile organic compounds from wood-based composite panels. • Assessment of volatile organic compounds during interspecific interactions. • Effect of volatile organic emissions from building and furnishing materials. • Evaluation and analysis of pressed wood, cellulose-based papers, and wooden bark were also reviewed. [ABSTRACT FROM AUTHOR]

New classes of biosorbents are needed for various environment remediation applications. Thus, a facile and benign approach to synthesize porous biosorbents was developed using acidic or alkaline one-step ball milling of hickory wood biomass (AcBH and AlBH, respectively) without any external heat treatment, and their properties were compared. AcBH and AlBH were richer in O-containing functional groups, had enhanced porous structure and greater ability to remove crystal violet (CV, 476.4 mg g -1 ) and Congo red (CR, 221.8 mg g -1 ) dyes from aqueous solution, respectively, relative to hickory wood ball milled at neutral pH. Freundlich isotherm and pseudo second order kinetic models best fitted CR and CV adsorption onto biosorbents, indicating a mainly surface complexation adsorption mechanism. Further, both sorbents exhibited excellent stability and dye adsorption reusability. These results demonstrate that acidic and alkaline one-step ball milling is a facile and efficient approach for converting wood biomass into environmentally friendly biosorbents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

The objective of this research was to evaluate the efficacy of cinnamon wood biochar (CWBC) in adsorbing sulfamethoxazole (SUL), which alleviates bioavailability and plant uptake. Batch studies at various pH, contact times, and initial SUL loading were used to study SUL adsorption in CWBC, soil, and 2.5% CWBC amended soil. SUL mitigation from plant uptake were examined using Ipomoea aquatica at different SUL contamination levels in the soil. The kinetic results were described by pseudo-second-order with maximum adsorption capacities (Q max ) of 95.64 and 0.234 mg/g for pristine CWBC and amendment, respectively implying that chemical interactions are rate-determining stages. Hill and Toth's model described the isotherm data for pristine CWBC, soil and CWBC amended soil as Q max of 113.44, 0.72, and 3.45 mg/g. Column data showed a great mobilization of SUL in loamy sand; however, when CWBC was added to the loamy sand, the mobilization was drastically reduced by 98.8%. The Ipomoea aquatica showed a great potential to SUL uptake and it depended on the contamination level; the SUL accumulation in plant was 9.6-13.8 and 19.1-48 mg/kg when soil was spiked with 5 and 50 mg/kg, respectively. The addition of 2.5% CWBC reduced root and shoot uptake by 30 and 95%, respectively in 5 mg/kg of SUL, whereas with 50 mg/kg of SUL, the root and shoot uptake was reduced by 60 and 61%, respectively. The current study suggested CWBC as a possible adsorbent that may be employed to reduce SUL bioavailability in environmental matrices., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Abstract: The use of the pesticides – DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) and lindane (gamma-hexachlorocyclohexane) – and of PCBs (polychlorinated biphenyls) has been limited or forbidden for several decades. Nevertheless, due to their persistence and bioaccumulative potentials they are still ubiquitous in the environment. Therefore, the main objective of this study was to determine analytical methods to analyse the pesticides lindane and DDT, its metabolites DDD (1,1-dichloro-2,2-bis(4-chlorophenyl)ethane) and DDE (1,1-dichloro-2,2-bis(4-chlorophenyl)ethene), and PCBs in waste wood and house dust. An ultrasonic extraction was performed followed by a sample clean up by filtration or silica gel column. The prepared samples were measured by GC/MS. Quantification through internal standard calibration delivered low limits of detection. Specific amounts of the target compounds were detected in all analysed dust samples. The comparison of the contamination between dust samples of eastern Germany (former German Democratic Republic – GDR) and western Germany partly revealed significant differences of the contamination levels. Furthermore, it was examined whether older wooden material might cause a constant volatilisation of pesticides in apartments. Waste wood samples of different contamination categories were analysed. Apparently, these samples are potentially responsible for a constant DDX (Σ(DDT, DDD, DDE)) and lindane volatilisation, but not for PCBs. [ABSTRACT FROM AUTHOR]

Abstract: Sorption of copper (Cu2+) by untreated and treated (bleaching and hydrolysis) aspen wood fibers, cellulose and lignin was examined to understand the Cu2+ sorption behavior by these natural sorbents. All sorbents were characterized by solid-state 13C NMR and FTIR. Bleaching broke up aromatic structures and increased hydrophilicity of the fibers, whereas hydrolysis decreased carbohydrate content, producing a more hydrophobic structure. Copper sorption was a function of pH; the percentage of Cu2+ sorption steadily increased from pH 1.5 to 4.5 with a maximum sorption amount at around pH 5.5 for all the materials. All isotherms fitted well to the Langmuir equation. Bleached sample (BL) had a highest sorption capacity, followed by untreated (UTR), cellulose (CEL), and hydrolyzed (HHY), while lignin (LIG) had little Cu2+ sorption under the studied conditions. The results suggested that carboxyl (–COOH) and hydroxyl (–CHOH) in carbohydrates are mainly responsible for Cu2+ sorption, and that ion exchange may be a main sorption mechanism for the studied sorbents. Additionally, the sorption capacity for Cu2+ on all sorbents decreased with the increase of the initial concentrations of Ca2+, Na+ or Al3+. Copper sorption decreased rapidly at low initial concentrations of Ca2+, Na+ or Al3+. However, the decline of Cu2+ sorption slowed down when initial Na+ and Ca2+ concentration was higher than 0.05M or initial Al3+ concentration was greater than 0.005M, indicating that specific adsorption may be taking place. Therefore, the majority of sorbed Cu2+ to aspen wood fibers could be through ion exchange (especially, for UTR, BL and CEL), while a faction of sorbed Cu2+ via inner-sphere complex (or specific adsorption). [Copyright &y& Elsevier]

Wood is rich in extractives and volatile oils that emit unpleasant odors and some harmful volatile organic compounds (VOCs). Chemical oxidation technologies processes high efficiency on the destruction of aqueous organic components via oxidation by radicals, however, wood block treatment scenarios suffer from the low availability of radicals in aqueous conditions owing to the special structure of the wood blocks, limitations of mass transfer and the short life of free radicals. Herein, ethylenediaminetetraacetic acid (EDTA) is selected as a chelating agent to synthesize EDTA-Fe 2+ chelate, thus introducing Fe 2+ into the wood by vacuum impregnation. The Fe 2+ is evenly distributed and immobilized in the wood to form a chemical oxidation system via in-situ activation of the dual oxidant (H 2 O 2 -PS), which truncates the contact distance between free radicals and extractives/volatile oils thus enhancing the removal efficiency. Various controlling factors, including EDTA/Fe 2+ molar ratio, Fe 2+ dosage, PS/H 2 O 2 molar ratio, and persulfate (PS) dosage are evaluated. The degradation products of VOCs by headspace solid-phase micro-extraction combined with gas chromatography-mass spectrometry (HS-SPME/GC-MS) indicate that the wood VOC removal rate is ∼80%. The Electron paramagnetic resonance (EPR) analysis further reveals that SO 4 - · and ·OH are the primary reactive species. The characterization of wood properties illustrates that the process has no destructive effect. The results of this work may provide a theoretical basis for feasibility of the practical application of the EDTA-Fe 2+ /H 2 O 2 -PS system., (Copyright © 2021. Published by Elsevier Ltd.)

The surface-dependent evaporation behavior of phthalates as semi-volatile organic compounds (SVOCs) on glass, wood, and polyurethane foam (PUF) was investigated. Three phthalates of di-2-ethylhexyl phthalate (DEHP), butyl benzyl phthalate (BBP), and dibutyl phthalate (DBP) were studied to compare the amount of gases vaporized from their surfaces. A 10 mL silicate glass vial was used to compare the gas equilibrium of the phthalates after 2 h. The gases accumulated in the air were transferred to a solid-phase microextraction (SPME) column and analyzed by gas chromatography-mass spectrometry (GC-MS). As correlated with the physicochemical properties of the phthalates, including molecular weights and vapor pressure, the surface-air partition coefficients (K sa ) were found to be in the range of 10 1 -10 5  m, 10 6 -10 7  m, and 10 7 -10 9  m on glass, wood, and PUF, respectively, implying that a significant amount of phthalates are retained on wood and PUF surfaces as compared to glass, and only a trace amount of phthalates can be volatilized into the air, especially the less volatile DEHP. The three-dimensional (3D) morphologies of glass and wood were also examined using a white-light interferometric surface profile microscope and an atomic force microscope (AFM). In contrast to smooth glass surfaces within the sub-micrometer vertical range, the wood surfaces exhibited uneven irregular structures at a height of 5-30 μm. The rough wood surfaces were found to adsorb substantial amounts of gases to prevent the effective volatilization of phthalates into the air, especially the low molecular DBP. Our results imply that wood and PUF surfaces may be superior to glass surfaces in storage and reduction of phthalates in the air, especially DBP., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In the present study, the activated carbon of lemon (ACL) was generated from Citrus limon wood waste and composited with Fe 3 O 4 nanoparticles. The ACL/Fe 3 O 4 magnetic composite was effectively used to eliminate Cd2+ from an aqueous solution. The active surface area values for ACL and ACL/Fe 3 O 4 magnetic composite were 25.99 m2/g and 38.70 m2/g, respectively indicating the effectiveness of Fe 3 O 4 nanoparticles in improving ACL active surface area. The response surface methodology with central composite design (RSM-CCD) was used to determine optimal values of pH, ACL/Fe 3 O 4 dose, contact time, and Cd2+ concentration on the decontamination efficiency. The Langmuir and Freundlich isotherm models had more potential to describe the adsorption process using ACL and ACL/Fe 3 O 4 , respectively. The Langmuir-based adsorption capacity was obtained as 28.2 mg/g (ACL) and 39.6 mg/g (ACL/Fe 3 O 4). A pseudo-second order (PSO) model was successfully applied to evaluate the adsorption process kinetic behavior. A higher value of α parameter for ACL/Fe 3 O 4 (5.7 mg/g.min) than that of ACL (3.5 mg/g.min) indicated that the magnetic composite had a greater tendency to absorb Cd2+. In addition, the Weber–Morris model showed that various mechanisms such as intraparticle diffusion and boundary layer effects may have a role in the adsorption process. The study of ad(de)sorption behavior showed that the adsorbents have a good ability to adsorb Cd2+ and no significant change in their performance has been made up to 4 times of reuse. Our results showed that ACL modification using Fe 3 O 4 nanoparticles improved the adsorption efficiency of ACL to remove Cd2+ from the aqueous solutions. [Display omitted] • The lemon activated carbon (ACL) was decorated with iron to produce ACL/Fe 3 O 4. • The BET values for ACL and ACL/Fe 3 O 4 were 25.9 m2/g and 38.7 m2/g, respectively. • The Cd removal by ACL and ACL/Fe 3 O 4 followed Langmuir and Freundlich, respectively. • The process kinetic behavior was described by pseudo-second order model. • The α value for ACL/Fe 3 O 4 (5.7 mg/g.min) was greater than that of ACL (3.5 mg/g.min). [ABSTRACT FROM AUTHOR]

In the current study, activated carbon oak wood (ACOW600) and modified activated carbon using ZnO (ACOW600/ZnO) and Fe 3 O 4 (ACOW600/ZnO/Fe 3 O 4 ) nanoparticles were used to remove methyl violet 2B dye (MV2B) from aqueous solutions. ACOW was synthesized at different temperatures (300-700 °C), and then the maximum MV2B removal efficiency (92.76 %) was achieved using ACOW synthesized at 600 °C. The morphology and characteristics of ACOW600, ACOW600/ZnO, and ACOW600/ZnO/Fe 3 O 4 were studied using surface analyzes. According to the results, the adsorbents indicated a high ability to absorb MV2B from liquid solution, and their kinetic behavior follows a pseudo-second-order kinetic. In addition, the equilibrium study revealed that the MV2B uptake by the ACOW600/ZnO/Fe 3 O 4 magnetic nanocomposite followed the Freundlich model. In contrast, the Langmuir model described the MV2B adsorption process using ACOW600 and ACOW600/ZnO. The maximum adsorption capacity (q m ) of MV2B using ACOW600, ACOW600/ZnO, and ACOW600/ZnO/Fe 3 O 4 was determined 26.16 mg g -1 , 37.05 mg g -1 , and 48.59 mg g -1 , respectively, indicating that modification of ACOW600 led to improve its performance in removing MV2B. The enthalpy (ΔH), entropy (ΔG), and Gibbs free energy (ΔS) parameters revealed that the decontamination of MV2B using the studied adsorbents was exothermic and spontaneous. Also, random interactions of MV2B molecules and adsorbent surfaces were reduced during the adsorption process. Textile wastewater was significantly treated by ACOW600, ACOW600/ZnO, and ACOW600/ZnO/Fe 3 O 4 adsorbents. The recycling of the adsorbents was demonstrated that the investigated adsorbents could be re-utilized many times in the MV2B removal process., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: It is well known that PM 2.5 generated by traffic or burning wood is pro-inflammatory and induces various adverse health outcomes in humans. In Sydney, New South Wales, Australia, the main anthropogenic contributors to particulate matter (PM) air pollution are wood combustion heaters, on-road vehicles, and coal-fired power stations. However, the relative toxicity of these local sources has not to date been investigated., Method: PM 2.5 was collected on filters from the same sampling site in Liverpool, one suburb of Sydney. According to the positive matrix factorisation and collection season, filters were representative of either day with high traffic-related air pollution (TRAP), wood smoke, or both TRAP and woodsmoke (mixed air pollution). The elemental composition of the PM was assessed by accelerator-based ion beam analysis techniques (i.e. PIXE & PIGE) and size by Dynamic Light Scattering. Toxicity and inflammation were assessed in-vitro in human bronchial epithelial cells by measuring interleukin-6 (IL-6), interleukin-8 (IL-8) release, and MTT., Results: Mixed air pollution (TRAP/wood smoke) PM had more nanometer (nm) sized PM than the other two groups. Using an in-vitro model of the lungs, the mixed air pollution PM was the most toxic, whereas the PM from woodsmoke induced greater IL-6 release than TRAP PM. There was no difference in the induction of IL-8 between the three sources of PM., Conclusion: Marked differences occur in the cellular response to PM from different sources, with differences in both toxicity and inflammation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.)

Coniferyl alcohol derived from lignin pyrolysis, is a potential tracer for wood burning emissions, but its atmospheric stability toward OH radicals is not well known. In this work, the degradation kinetics of coniferyl alcohol by OH radicals was studied using a flow reactor at different OH concentrations, temperatures, and relative humidity (RH). The results showed that coniferyl alcohol could be degraded effectively by OH radials, and the average second-order rate constant (k 2) was (11.6 ± 0.5) × 10−12 cm3 molecule−1 s−1 at the temperature and RH of 25 °C and 40%, respectively. Additionally, increasing temperature facilitated the degradation of coniferyl alcohol and the Arrhenius equation could be expressed as k 2 = (1.7 ± 0.3) × 10−9exp [-(1480.2 ± 55.6)/T] at 40% RH. Meanwhile, increasing RH had a negative impact on the degradation of coniferyl alcohol. According to the k 2 obtained under different conditions, the atmospheric lifetime of coniferyl alcohol was in the range of 13.5 ± 0.4 h to 22.9 ± 1.4 h. The results suggested that the atmosphere lifetime of coniferyl alcohol was predominantly controlled by OH radicals. Image 1 • Degradation kinetics of coniferyl alcohol by OH radicals was studied. • High temperature and low RH facilitated the degradation of coniferyl alcohol. • OH radicals play a dominant role in the degradation of coniferyl alcohol. [ABSTRACT FROM AUTHOR]

Sustainable materials are urgently desired for treatment of radioactive cesium (Cs) contaminated water to safe-guard the public health. Apart from the synthetic ligand-based materials, the Mangrove charcoal modified adsorbent was fabricated for assessing of Cs removal from waste sample. The raw charcoal was oxidized using nitrification approach and diverse oxygen containing carboxyl, carbonyl and hydroxyl functional groups were introduced. After modification, the adsorbent characteristics were drastically changed as compared to the charcoal during the measurement of FTIR, N 2 adsorption-desorption isotherms and SEM micrographs. The data clarified that charcoal modified adsorbent was exhibited high Cs transport through the inner surface of the adsorbent based on bonding ability. The adsorbent was shown comparatively slow kinetics to Cs ion; however, the adsorption capacity was high as 133.54 mg/g, which was higher than the crown ether based conjugate materials. The adsorption data were followed to the Langmuir adsorption isotherms and the monolayer coverage was possible due to the data presentation. The presence of high amount of Na and K were slightly interfered to the Cs adsorption by the charcoal modified adsorbent, however; the Na and K concentration was 350-600 folds higher than the Cs concentration. Then the proposed adsorbent was selective to Cs for the potential real radioactive Cs contaminated water. The volume reduction was established rather than desorption and reuses advantages. More than 99% volume reduction was measured by burning of Cs adsorbed adsorbent at 500 °C for ensuring the safe storage and disposal of used adsorbent. Therefore, the charcoal modified adsorbent may open the new door to treat the Cs containing wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Household biofuel burning contributes a large proportion of fine particulate matter (PM 2.5 ), black carbon (BC), and organic carbon (OC) emissions in many parts of the world. Dilution sampling has been widely used to characterize PM 2.5 emitted from biofuel burning. The residence time in the dilution chamber is a key parameter for accurate sampling. However, residence time has not yet been adequately characterized for biomass combustion. In this work, we investigated the effects of residence time of dilution sampling on PM 2.5 emissions from a typical Chinese household stove burning typical biofuels including three major crop wastes and one type of wood. The filter based measurements indicated that the emission factors for PM 2.5 and its main chemical components such as OC, EC, Cl - , and K + did not vary with the residence time over the range of 1-80 s. Theoretical estimation of average time scale for achieving dynamic equilibrium (τ s ) between the gas and particle phase in the dilution sampling system was less than 1 s. Both the measurement study and theoretical simulations indicated that dilution sampling with a residence time of 1s can provide adequately reliable results for PM 2.5 emissions from biofuel burning under the condition of these experiments. A simple way to estimate the equilibration time based on measured average PM 2.5 concentration was proposed. Recommendations are provided for the residence time for dilution sampling of accurate measurements of PM 2.5 emissions from biofuel burning., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Data for source apportionment estimation was obtained from combustion of 11 types of biomass (rubber wood, palm kernel, palm fiber, sugarcane bagasse, sugarcane leaves, maize residue, rice stubble, rice straw, Xylocarpus moluccensis, Avicennia alba Blume and Rhizophora mucronata) and bituminous coal. Combustion was carried out in a tube furnace and emitted particulate matter (PM) was collected using a nanosampler that segregated particle sizes down to 0.1 μm. Emission factors of PM < 0.1 μm were in the range of 0.11-0.28 g kg -1 (∼1-8% of total PM), except in the case of Rhizophora mucronata, which had an emission factor of 0.071 ± 0.004 g kg -1 (∼18% of total PM). The dominant polycyclic aromatic hydrocarbons (PAHs) found on PM < 0.1 μm were chrysene from combustion of rubber wood, palm kernel, palm fiber, maize residue, Xylocarpus moluccensis, Avicennia alba Blume, Rhizophora mucronata and bituminous coal; benzo[b]fluoranthene from combustion of rice straw, sugarcane bagasse and sugarcane leaves; and benzo[k]fluoranthene from rice stubble combustion. The emission factors of PAHs bound to PM < 0.1 μm from biomass combustion ranged from 0.005 to 0.044 mg kg -1 and the emission factor from bituminous coal combustion was 0.1411 ± 0.0004 mg kg -1 . The carcinogenic potency equivalent or benzo[a]pyrene equivalent was highest from bituminous coal combustion (0.1252 mg kg -1 ) and between 0.0019 and 0.0192 mg kg -1 from biomass combustion. However, emission factors of both PM and particle-bound PAHs from biomass combustion were affected by moisture content of biomass and moisture contents of biomass used in this study were quite low, ranging from 0.165 to 0.863%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this study, cost-effective cellulosic biomass based activated wood charcoal was developed from Japanese Sugi tree (Cryptomeria japonica) by concentrated nitric acid modification for adsorption of Cs from contaminated water. The physicochemical properties of specimens were investigated using N 2 adsorption-desorption isotherms (BET method), FESEM, FTIR, and XPS spectra analysis. The experimental results revealed that the surface area of the raw wood charcoal was significantly decreased after boiling nitric acid modification. However, several oxygen-containing acidic function groups (-COOH, -CO) were introduced on the surface. The adsorption study confirmed that the equilibrium contact time was 1 h, the optimum adsorption pH was neutral to alkaline and the suitable adsorbent dose was 1:100 (solid: liquid). The maximum Cs was removed when the concentration of Na and K were lower (5.0 mM) with Cs in solution. The Cs adsorption processes well approved by the Langmuir isotherm and pseudo-second-order kinetic models and the maximum adsorption capacity was 35.46 mgg -1 . The Cs adsorption mechanism was clearly described and it was assumed that the adsorption was strongly followed by chemisorptions mechanism based on the adsorbent surface properties, kinetic model and Langmuir isotherm model. Most importantly, about 98% of volume reduction was obtained by burning (500 °C) the Cs adsorbed charcoal, which ensured safe storage and disposal of radioactive waste. Therefore, this study can offer a guideline to produce a functional adsorbent for effective Cs removal and safe radioactive waste disposal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The study was conducted to assess the performance of improved and traditional cookstoves using wood as a fuel and three combinations of other fuel mixes - (i) wood and cow dung, (ii) wood and mustard stalks, and (iii) cow dung and mustard stalks). Energy and emission parameters such as specific energy consumption (SEC), emission factors (EFs) of carbon monoxide (CO), particulate matter (PM) and black carbon (BC) were used to compare four different types of cookstoves. These included top-feed forced draft (TF-FD), top-feed natural draft (TF-ND), front-feed natural draft (FF-ND) and front-feed traditional (FF-TR) cookstoves. Controlled cooking test (CCT) was used as the test protocol. The results showed the performance of improved cookstove technologies can vary based on the fuel used for cooking. It was observed that emission factors for PM and CO increased by 67-96% and 45-90% respectively when all three improved cookstoves were tested with three fuel combinations against wood as cooking fuel. Among the tested cookstoves, a marked difference was observed between performance of forced draft and natural draft cookstoves. Forced draft cookstoves emitted higher amount of all pollutant emissions compared to natural draft cookstoves when used with mustard stalks in combination with either wood or cowdung. The results are of critical importance given that forced draft cookstoves have been promoted in geographical regions where fuel mix use is prevalent. Therefore, forced draft cookstove might not be the right choice when the goal is climate mitigation and reduction in impact on human health. It is imperative to study comprehensively the influence of various field variables on performance of cookstoves, which have severe implications on the performance of cookstoves., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Magnetic ferrite/biochar composites are a kind of promising adsorbents due to their high adsorption efficiency and facile magnetic separation; however, their synthesis is associated with high cost and secondary environmental impacts. In this study, a novel Mn-Zn ferrite/biochar composite (MZF-BC) is synthesized via a green two-step biocheaching and hydrothermal method using waste batteries and pine sawdust. Characterization results indicate that the introduced Mn-Zn ferrite particles are successfully embedded and coated on biochar (BC), and synthesized MZF-BC 50 with 50% BC content exhibits best performance with a specific surface area of 138.5 m 2  g -1 , the saturation magnetization of 27.5 emu g -1 and CEC value of 53.2 mmol 100 g -1 . The maximum adsorption capacity of Pb 2+ is 99.5 mg g -1 based on the Langmuir sorption isotherm study at 298 K, and pseudo-second-order model accurately describes the adsorption process. Regeneration test suggests that MZF-BC 50 can be efficiently reused for 6 cycles. In addition, it exhibits a good selective Pb 2+ and Cd 2+ removal performance in lead-acid battery wastewater. The results illustrate that this newly developed material has low cost and rapid remediation of Pb 2+ as good application potential., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In the present study, industrial wood flour waste was selected for the first time as the precursor to produce biochar (WFB). The WFB was then used to prepare WFB/BiOBr visible-light photocatalysts, in which WFB acted as the carbon support to enhance the photocatalytic performance of BiOBr. Specifically, the impact of WFB pyrolysis temperature on the visible-light photo-removal performance of WFB/BiOBr was studied through degrading rhodamine B and reducing Cr(VI). The results indicated that when the pyrolysis temperature was 600 °C, the prepared WFB (600-WFB) had the highest graphitization degree, which afterwards significantly enhanced the visible-light photocatalysis performance of the BiOBr. Having higher graphitization degree, 600-WFB/BiOBr exhibited the highest photocatalytic capability. With a dosage of 0.5 g/L, the 600-WFB/BiOBr could completely remove to 20 mg/L of RhB and 5 mg/L of Cr(VI) within 90 min. Since wood flour is an abundantly existed industrial bioresource waste and easily pyrolyzed to prepare biochar, WFB is a promising alternative to replace traditional carbonaceous materials for the design of green and high-efficient visible-light photocatalysts for environmental remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Green nanoscale zero iron (nZVI) on an oak wood biochar support was prepared from tea polyphenol (TP-nZVI-OB), and applied to the removal of hexavalent chromium (Cr(VI)) from aqueous solution. The effects of experimental parameters on the Cr(VI) removal were evaluated by varying the Fe/C mass ratio, contact time, initial pH, and initial Cr(VI) concentration. The Cr(VI) removal performance of the TP-nZVI-OB was optimized at an Fe/C mass ratio of 2:1. The initial pH significantly affected the Cr(VI) removal, and 99.9% of the Cr(VI) was eliminated at pH 2.0. The kinetic data were well fitted to a pseudo-second order model, indicating that Cr(VI) removal was dominated by chemisorption. The successful TP-nZVI-OB synthesis and effective Cr(VI) removal mechanisms were confirmed by multiple techniques. The reaction between Cr(VI) and TP-nZVI-OB (2:1) involved multiple processes (sorption, reduction and co-precipitation), clarifying that TP-nZVI-OB is a potentially superior composite for Cr(VI) treatment of contaminated aqueous solution., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A woody-biochar was added to waste biomass during a composting process. The resulting compost-char was amended to a metal contaminated soil and two plant species, L. perenne and E. sativa, were grown in a pot experiment to determine 1) plant survival and stress factors, 2) uptake of metals to plants and, 3) chemical characteristics of sampled soils and pore waters. Compost supplemented with biochar after the composting process were also tested, as well as a commercially available compost, for comparison. Co-composting with biochar hastened the composting process, resulting in a composite material of reduced odour, increased maturity, circum-neutral pH and increased moisture retention than compost (increase by 3% of easily removable water content). When amended to the soil, CaCl 2 extractable and pore water metals s were reduced by all compost treatments with little influence of biochar addition at any tested dose. Plant growth success was promoted furthest by the addition of co-composted biochar to the test soil, especially in the case of E. sativa. For both tested plant species significant reductions in plant metal concentrations (e.g. 8-times for Zn) were achieved, against the control soil, by compost, regardless of biochar addition. The results of this study demonstrate that the addition of biochar into the composting process can hasten the stability of the resulting compost-char, with more favourable characteristics as a soil amendment/improver than compost alone. This appears achievable whilst also maintaining the provision of available nutrients to soils and the reduction of metal mobility, and improved conditions for plant establishment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Antibiotics and heavy metals are frequently detected simultaneously in water environment. Effective elimination methods for antibiotics and heavy metals pollution should deserve our attention. This study investigates the adsorption performance of biochar modified with nano-hydroxyapatite (nHAP) on tylosin (TYL) and Cu from water simultaneously. Composite adsorbents of nHAP and biomass, derived from three waste residues, which were wood-processing residues (WR), wheat straw (WS) and Chinese medicine residues (CMR), were prepared. According to the results of orthogonal experiment, the degree of influence of the three factors on TYL and Cu were the pyrolysis temperature > the proportion of nHAP and biomass > the sources of biomass, and pyrolysis temperature> the sources of biomass> the proportion of nHAP and biomass, respectively. The optimum conditions for nHAP@biochar were screened. At pH < 7.0, the adsorption quality of TYL increased with pH increased, while at pH > 7.0, the adsorption quality of TYL changed slightly. At low pH, Cu and TYL could compete for the same adsorption sites on nHAP@biochars. The adsorption amount of TYL and Cu were both increased with increasing of the temperature. Compared with Langmuir model, Freundlich model could better fit the TYL adsorption on nHAP@biochars, with K f values of TYL 62.35 (mmol/kg) (L/mmol) n (WR1) and 4.84 (mmol/kg) (L/mmol) n (CMR1), respectively., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A common strategy to improve indoor air quality in households burning coal and biomass is the introduction of advanced combustion solid fuel stoves, which can use existing fuels yet emit fewer pollutants. Chemical composition of PM is affected by numerous combustion parameters, but is often not considered in energy transitions, despite varying toxicity among chemical components. We analyzed PM 2.5 emissions from combustion of solid fuels (coal, wood, and straw; whole and pelletized) in a variety of stoves (cookstoves and heating stoves; traditional and semi-gasifier, including forced versus natural draft and fixed versus reciprocating grate). To assess the effects of fuel and stove type on PM 2.5 composition, we measured elemental carbon (EC), organic carbon (OC), water-soluble OC, water-soluble inorganic ions (e.g. SO 4 2- , Cl - , K + ), and organic molecular markers. PM 2.5 emissions from traditional stoves were mostly carbonaceous: 76-90% organic matter (OM), 5-6% EC, and less than 2% inorganic ions. In contrast, semi-gasifier stoves emitted more inorganic PM 2.5 : on average, ions comprised 65%, 9% was OM, and 4% was EC. Within the semi-gasifier cookstoves, forced-draft cookstove emissions had lower OM (1-3%) and higher ion concentrations (84-88%) than the natural-draft cookstove (5-14% OM, 30-83% ions). Levoglucosan was detected in PM 2.5 from combustion of wood in the traditional cookstove and biomass pellets in the natural-draft semi-gasifier cookstove, but not from wood pellets in the forced-draft semi-gasifier cookstove. Across a range of different fuels and stoves, stove type influenced emitted PM composition more than fuel type, underscoring the impact of combustion conditions on PM chemical composition., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Wood-based biochar, as a metal-free heterogeneous activator of peroxydisulfate (PDS), was successfully prepared by pyrolysis of polar sawdust for efficient removal of Acid Orange 7 (AO7). The results demonstrate PDS could be effectively activated by wood-based biochar, and AO7 was rapidly eliminated in a wide range of pH value (3.0-10.0) with AO7 removal achieved ≥ 99.3% after 14 min reaction. The dominant reactive species in the biochar/PDS system were verified via radical quenching tests and electron paramagnetic resonance (EPR) technique. It is speculated that sulfate radicals (SO 4 •- ) and hydroxyl radicals ( • OH) were formed on the surface of biochar. Based on the results of X-ray photoelectron spectroscopy (XPS), π-electron density and oxygen-containing functional groups (especially C-OH) on biochar surface were active centers for the catalytic reaction. Recycle experiments of biochar for 4 runs were carried out and the regeneration method of the catalyst was also studied., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Biochar is a promising material for facilitating the reclamation of oil sands process water (OSPW); however, how biochar properties can be optimized for metal removal from OSPW is not well studied. This study was conducted to determine relationships among feedstock type, pyrolysis condition, biochar property, and lead(II) adsorption capacity to demonstrate the potential use of biochar for metal removal from a synthetic OSPW. Sawdust, canola and wheat straw, and manure pellet were pyrolyzed at 300, 500, and 700 °C, with or without steam activation. Increasing pyrolysis temperature increased, with a few exceptions, biochar pH, surface area, and carbon content, but decreased hydrogen and oxygen contents and surface functional groups. Steam activation increased surface area but did not affect other properties. For non-steam-activated biochars, canola and wheat straw biochars produced at 700 °C had the highest lead(II) adsorption capacity (Q max&#95;Pb ), at 108 and 109 mg g -1 , respectively. Increasing the pyrolysis temperature increased Q max&#95;Pb due to increased biochar pH, ash content, and surface area by increasing precipitation, ion exchange, and inner-sphere complexation of lead(II). Steam activation increased lead(II) adsorption capacity for most biochars mainly due to the increased surface area, with the highest Q max&#95;Pb at 195 mg g -1 for canola straw biochar pyrolyzed at 700 °C with steam activation. The adsorption with time followed a pseudo-second order kinetic model. The results of this study will help select most effective biochars that can be produced from locally available agricultural or forestry byproducts that are optimized for metal removal from synthetic OSPW., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Selection of an appropriate biochar as a soil amendment requires a thorough investigation of the effects on soil ecosystems and adjacent water systems via leaching. Different biochar characteristics influence retention or leaching of different soil and biochar components. A lab lysimeter study was conducted to investigate carbon (C) balance and leachate quality with biochar additions. Biochar made from wood pellets (WP) and sewage sludge (SS) produced at 400 °C (WP400 and SS400) and 700 °C (WP700 and SS700), respectively, were applied to silt loam soil at an application rate of 4%. Fluorescence excitation-emission spectrophotometry (EEMs) was utilized to understand the compositional changes in leachate dissolved organic carbon (DOC). Our results show that DOC contributed the largest portion of C leaching loss. The WP treatments increased DOC mass loss, but did not significantly change leachate DOC quality. SS400, in comparison, increased mass loss of DOC and SS700 decreased it probably due to its higher adsorptive capacity to DOC. Unlike WP treatments, SS treatments significantly changed leachate DOC quality. Chemical oxygen demand (COD) was reduced with SS400 and SS700 biochar additions, which is assumed to be related to SS biochar's high oxygen-containing surface functional groups. Reduction in total nitrogen (TN) leaching by WP700 and SS700 treatments might be related to the higher micropore surface area. Over all, our findings imply that changes in the different components of the leachate from biochar-amended soil are related to different biochar properties, such as labile matter content, total surface area, micropore volume and cation exchange capacity., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Two common organic wastes from agriculture (rice straw) and forestry (sawdust) were applied to a petroleum-contaminated soil to estimate their effectiveness in the removal of total petroleum hydrocarbons (TPHs) and polycyclic aromatic hydrocarbons (PAHs). Rice straw was the more effective amendment than the other treatments in reducing TPH contents and addition of sawdust resulted in a significant decrease in PAH removal, particularly high-molecular-weight (5-6 ring) PAHs. Principal coordinates analysis (PCoA) indicates that rice straw treatment separated only the bacterial community but sawdust greatly affected both the soil bacterial and fungal communities. Moreover, the abundance of some petroleum degraders such as the bacteria Sphingomonas, Idiomarina and Phenylobacterium and the fungi Humicola, Wallemia and Graphium was promoted by inputs of the two agricultural and forestry wastes. These results highlight the potential of waste applications in accelerating hydrocarbon biodegradation which may be attributed to the enrichment of keystone taxa that show strong positive associations with hydrocarbon degradation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study, the influences of feedstock and pyrolysis temperature on carbon fractions of biochar were investigated. Four types of organic wastes (rice straw (RS), pine wood (PW), pig manure (PM) and sewage sludge (SS)) were pyrolyzed at different temperatures (300 °C, 400 °C, 500 °C, 600 °C and 700 °C). Biochar produced at low temperature exhibited high yields, high dissolved organic carbon (DOC) content and unstable organic carbon content. In contrast, biochar formed at high temperature showed high C content and C stability with a low O/C and H/C ratios. In addition, the biochar pyrolyzed from PW contained the lowest DOC of the four biochar types. The properties of DOC fractions (F1, F2 and F3) released from biochar differed depending on feedstock, pyrolysis temperatures, and extraction procedures. The highest specific ultraviolet absorbance at 254 nm of the F1 and F2 fractions were observed for RS biochar, suggesting that more aromatic organic matter was present in sequentially extracted fractions of RS biochar than in extracts from the other biochars. In addition, the hot water extracts (F2) mostly showed higher aromaticity than cold water extracts (F1). The stability of biochars was greatly enhanced at pyrolysis temperatures >500 °C. If the biochars produced in this study were to be used for carbon sequestration in soil, the first priority should be PW, followed in order by RS and PM., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

There is increasing concern about the use of chromated copper arsenate (CCA) treated timber due to the possible leaching of toxic metals or metalloids. CCA-treated timber waste are currently stockpiled across Australia with limited information about their risks to the environment or human health. In this study, the treatment and utilisation of CCA-treated timber waste as garden mulch, garden retaining walls, and soil additive were investigated. Iron materials were used as immobilising agents. The bioavailability of Cr, Cu and As to Spinacia oleracea from CCA-treated timber, before and after treatment, was determined in the context of human health risk assessment. The results showed that the iron-based treatments resulted in significant decreases in the concentrations of Cu and As in spinach grown in CCA-treated timber in soil. Analyses of CCA derived Cu and As in spinach showed that they accumulated in the roots rather than in the leaves. The risks of toxicity to humans varied for different utilisation scenarios and the immobilisation amendments were shown to reduce carcinogenic and non-carcinogenic risks. The information obtained in this study can inform development of utilisation options for CCA-treated timber wastes., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Black carbon such as biochar has been shown to support microbial redox transformation by accepting and/or donating electrons. Electron storage capacity (ESC) is an important property that determines the capacity of a biochar to mediate redox processes in natural and engineered systems. However, it remained unclear whether a biochar's ESC is constant and reversible and if so to what extent, over what redox potential range ESC is distributed, and what fraction of the ESC is microbially accessible. In this study, we developed chemical methods that employed combinations of reductants and oxidants of different potentials - Ti(III) citrate, ferricyanide, dithionite, and dissolved O 2 - to measure the ESC of Soil Reef biochar, a wood-derived biochar that can serve as an electron donor or acceptor for Geobacter metallireducens. For a given oxidant-reductant pair, the ESC obtained over multiple redox cycles was constant and fully reversible, though lower than that of the virgin biochar. Pore diffusion within biochar particles was rate-limiting and controlled the timescale for redox equilibrium. Results suggest that redox-facile functional groups in biochar were distributed over a broad range of potentials. The ESC measured using dithionite indicates approximately 22% of the biochar's reversible ESC was accessible to G. metallireducens. We propose that reversible ESC may be regarded as a constant and quantifiable property of black carbon., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Biochar has shown a unique electrochemical property being involved in various redox reactions in soil and water. In this study, the electron donating capacities (EDCs) of biochar pyrolyzed at 200-800 °C from pine wood, barley grass and wheat straw were investigated by using the mediated electrochemical oxidation method. The EDC values for all biochar were in the range of 0.18-1.83 mmol e - (g biochar) -1 , showing the increase as the temperature increased from 200 °C to 400 °C, the decrease from 400 °C to 650 °C, and then increase from 650 °C until to 800 °C. At low and intermediate temperatures of 200-650 °C, the EDCs were mainly attributed to the phenolic hydroxyl groups, while the conjugated π-electron system associated with aromatic structure dominated the EDCs of biochar at the high temperatures of over 650 °C. The barley grass- and wheat straw-derived biochar had higher EDCs than the pine wood-derived biochar, resulting from the higher phenolic hydroxyl groups in the former samples than the latter one. In conclusion, the reductive property of biochar was mainly attributed to both phenolic hydroxy group and conjugated π-electron system associated with aromatic structure, depending on the pyrolytic temperature and feedstock source. The results will help us to obtain a complete view on the role of biochar in biogeochemical redox reactions and consider developing biochar with controlled redox properties for specific environmental applications such as electron shuttle and catalyst material., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This research aims to investigate the effects of irradiation energy and residence time of soft X-ray irradiation in the decomposition of sixteen polycyclic aromatic hydrocarbons (PAHs) in smoke particles emitted from the Para rubber wood burning. The burning process was carried out in a tube furnace and the soft X-ray radiation used had a wave length of 0.13-0.41 nm. The irradiated (IR) and non irradiated (N-IR) smoke particles were collected simultaneously using a 10-stage Andersen sampler equipped with an inertial-filter stage (ANIF), in order to determine the physicochemical characteristic of both IR and N-IR smoke particles, including particle size distribution and concentration, and particle-bound PAHs concentration. Results show that the nano-size smoke particles contained the highest amount of PAHs and of carcinogenic potency equivalent (BaP-TEQ). About 75% of PAH compounds on the total smoke particles were decomposed at the highest irradiation energy. Moreover, 4-6 ring PAHs in nanoparticles (<70 nm) were decomposed of up to about 91% at the highest irradiation energy. The decomposition efficiency of PAHs was influenced by particle size, PAHs boiling temperature and irradiation energy. It was higher for PAHs with lower boiling temperature and smaller size particles, while the effect of residence time was not significant., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In the present study, a methodology involving hydrophilic interaction liquid chromatography (HILIC) and electrospray (ESI) tandem mass spectrometry (MS/MS) was developed for measurement of anhydrous monosaccharides as markers for wood burning in atmospheric aerosols, PM 10 . No extensive sample preparation, other than ultrasound-assisted solvent extraction and evaporation, was applied. A pentahydroxysilica column enabled separation of levoglucosan from mannosan and galactosan within 5 min and the quantitative performance was validated using the standard reference materials (SRM) 1649a and 1649b. The experimentally obtained results for SRMs were in agreement with values previously reported in other studies. Achieved instrumental limits of detection (LODs) were below 10 pg injected on column, corresponding to LODs in air lower than 0.10 ng/m 3 for all measured isomers for 2-3 day sampling with 1.0 m -3  h -1 sampling rate. The validated method was used for the determination of levoglucosan and its isomers in atmospheric aerosols collected in three different Swedish urban areas during the winter and summer time in 2017. The total measured concentrations for levoglucosan and galactosan + mannosan were determined to be between 78 and 167 ng/m 3 in January 2017, which is approximately 10-times higher compared to the levels detected in July, reflecting the higher frequency of wood burning for heating during the cold season. Calculated concentration ratios between levoglucosan and its isomers in the urban area samples indicated mostly mixed softwood/hardwood combustion in winter time; on the other hand, softwood burning was observed as the major emission in summer time., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This work was aimed at studying particulate matter (PM) in the indoor atmosphere of two flats where airtight biomass systems were used for domestic heating. PM 10 and PM 2.5 samples were collected by means of nine parallel sampling units, located in the outdoor and indoor areas of each flat. The samples were analyzed for PM macro-components (organic carbon, elemental carbon, macro-elements and inorganic ions) and for the soluble and residual fractions of micro-elements; the influence of the main PM sources on the indoor air quality was evaluated. The results confirm that infiltration from outdoor represents the main source of fine particles, while dust re-suspension, enhanced by the movements of the inhabitants, is one of the most important sources of coarse particles. Biomass-fueled heating systems are a significant source of indoor pollution, mainly due to the cleaning operations required for the removal of residual ash, which release particles in both the fine and the coarse size range. The impact of these operations resulted in indoor to outdoor ratios higher than one for most of the considered PM components. Very high amounts of copper and manganese, elements likely involved in the generation of oxidative stress, were released into the environment during ash removal from the pellet stove. Although this operation was very limited in time (about 15 min), the average concentration of Cu and Mn in PM 10 and PM 2.5 during the study period (18 days) was more than six times (Cu) and about twice (Mn) the concentration values measured outdoors., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Biochar is increasingly deemed a potential sorbent for contaminants in soil and water remediation. We tested three biochars from different feedstocks (cattle manure, grain husk, and wood chips) produced at relatively low pyrolysis temperature (450 °C), for their sorption behavior towards trichloroethylene (TCE) and tetrachloroethylene (PCE) in single- and bi-solute systems. In single-solute experiments, all biochars show stronger sorption for TCE (about 50% based on solubility-normalized Freundlich coefficients). The lower sorption of PCE is attributed to steric effects, e.g. size exclusion in small micropores and specific interactions. Plant-derived, carbon-rich biochars with high specific surface area and microporosity predominantly sorb via pore-filling, as also observed in activated carbon. Biochar produced from manure, with higher ash content and polarity, and smaller total pore volume (PV tot ), shows significant contribution of partitioning. These findings also apply to bi-solute systems. TCE and PCE show different competition behavior depending on biochar properties. Plant-based biochars are pore-filling-dominated and show strong competition. However, competition behavior in microporous biochars depends on the concentration range. Manure biochar with high polarity and low PV tot shows significant partitioning and therefore less competition. Compared to the plant-based chars competition in manure biochar is not concentration-dependent. These results indicate that biochars with a large fraction of non-carbonized phase facilitate non-competitive sorption and might be a valuable sorbent in mixed contaminant systems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Four different types of fuel blends containing demolition and construction wood and household waste were combusted in a small-scale experimental set-up to study the effect of fuel composition on the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), chlorobenzenes (PCBzs), chlorophenols (PCPhs) and polycyclic aromatic hydrocarbons (PAHs). Two woody materials, commercial stemwood (ST) and demolition and construction wood (DC) were selected because of the differences in their persistent organic pollutants (POPs), ash and metals content. For household waste, we used a municipal solid waste (MSW) and a refuse-derived fuel (RDF) from MSW with 5-20 wt% and up to 5 wt% food waste content respectively. No clear effect on the formation of pollutants was observed with different food waste content in the fuel blends tested. Combustion of ST-based fuels was very inefficient which led to high PAH emissions (32 ± 3.8 mg/kg fuel ). The use of DC clearly increased the total PCDD and PCDF emissions (71 ± 26 μg/kg fuel ) and had a clear effect on the formation of toxic congeners (210 ± 87 ng WHO 2005 -TEQ/kg fuel ). The high PCDD and PCDF emissions from DC-based fuels can be attributed to the presence of material contaminants such as small pieces of metals or plastics as well as timber treated with chromated copper arsenate preservatives and pentachlorophenol in the DC source., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Although several global/regional studies have detailed the high level of polycyclic aromatic hydrocarbons in urban areas worldwide, unfortunately, Nepal has never been part of any global/regional regular monitoring plan. Despite few sporadic studies exist, the systematic monitoring and integrated concentration of PAHs in urban region of Nepal are lacking. In this study, the concentrations, sources, and health risk assessment of 16 PAHs in air (n = 34) were investigated in suspected source areas/more densely populated regions of Nepal. Four potential source areas in Nepal were focused as it was conjectured that urban centers in plain areas (Birgunj and Biratnagar) would possibly be more influenced by PAHs as a result of intense biomass/crop residue burning than those in hilly areas (Kathmandu and Pokhara). The overall concentrations of ∑ 16 PAHs ranged from 4.3 to 131 ng/m 3 (median 33.3 ng/m 3 ). ∑ 16 PAH concentrations in plain areas were two folds higher than those in hilly areas. PHE was the most abundant followed by FLUA, PYR, and NAP, which accounted for 36%, 15%, 12%, and 9% of ∑ 16 PAHs, respectively. Principal component analysis confirmed that PAHs in highly urbanized areas (Kathmandu and Pokhara) were related to diesel exhausts and coal combustion, while PAHs in less urbanized regions (Birgunj and Biratnagar) originated from biomass and domestic wood combustions. Furthermore, in the urban areas of Nepal, vehicular emission could also influence atmospheric PAHs. The lifetime cancer risk per million populations due to PAH exposures was estimated to be higher for plain areas than that for hilly areas, suggesting a relatively greater risk of cancer in people living in plain areas., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The aim of this study was to simulate a banned but widely spread practice of co-combustion of plastic with wood in a small residential boiler and to quantify its impact on emissions of gaseous pollutants, particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and 1,3,5-triphenylbenzene (135TPB), a new tracer of polyethylene plastic combustion. Supermarket polyethylene shopping bags (PE) and polyethylene terephthalate bottles (PET) were burnt as supplementary fuels with beech logs (BL) in an old-type 20 kW over-fire boiler both at a nominal and reduced heat output. An impact of co-combustion was more pronounced at the nominal heat output: an increase in emissions of PM, total organic carbon (TOC), toxic equivalent (TEQ) of 7 carcinogenic PAHs (c-PAHs) and a higher ratio of c-PAHs TEQ in particulate phase was observed during co-combustion of both plastics. 135TPB was found in emissions from both plastics both at a nominal and reduced output. In contrast to findings reported in the literature, 135TPB was a dominant compound detected by mass spectrometry on m/z 306 exclusively in emissions from co-combustion of PE. Surprisingly, six other even more abundant compounds of unknown identity were found on this m/z in emissions from co-combustion of PET. One of these unknown compounds was identified as p-quaterphenyl (pQ). Principal component analysis revealed strong correlation among 135TPB, pQ and five unknown compounds. pQ seems to be suitable tracers of polyethylene terephthalate plastic co-combustion, while 135TPB proved its suitability to be an all-purpose tracer of polyethylene plastics combustion., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Tetracycline (TET) is commonly used to treat bacterial diseases in humans and chickens (Gallus gallus domesticus), is largely excreted, and is found at elevated concentrations in treated sewage sludge (biosolids) and poultry litter (excrement plus bedding materials). Routine application of these nutrient-and carbon-enriched materials to soils improves fertility and other characteristics, but the presence of antibiotics (and other pharmaceuticals) in amendments raises questions about potential adverse effects on biota and development of antibiotic resistance in the environment. Hazard risks are largely dictated by sorption-desorption and diffusion behavior in amendments, so these processes were evaluated from sorption-desorption equilibrium isotherm and diffusion cell experiments with four types amendments (biosolids, poultry manure, wood chip litter, and rice hull litter) at three temperatures (8 °C, 20 °C and 32 °C). Linear sorption-desorption equilibrium distribution constants (Kd) in native amendments ranged between 124-2418 L kg -1 . TET sorption was significantly increased after treatment with alum, and there was a strong exponential relationship between Kd and the concentration of bound Al 3+ in amendments (R 2  = 0.94), which indicated that amendments contained functional groups capable of chelating Al 3+ and forming metal bridges with TET. Effective diffusion coefficients of TET in amendments ranged between 0.1 and 5.2 × 10 -6  cm 2  s -1 , which were positively related to temperature and inversely related to Kd by a multiple regression model (R 2  = 0.86). Treatment of organic amendments with alum greatly increased Kd, would decrease D s , and so would greatly reduce hazard risks of applying these organic amendments with this antibiotic to soils., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate the efficiency of a large scale washing/wet sieving technique for a soil contaminated with wood impregnation chemicals by 1) defining the final distribution of trace elements (As, Cu, Cr, Zn) and polycyclic aromatic hydrocarbons (PAH) in separated soil particle size fractions; and 2) defining the leaching behavior of the contaminants in these soil fractions. A soil washing experiment was implemented at waste management facility in Sweden using a full scale soil sorting and washing equipment. Five tons of soil was loaded to the equipment and wet-sieved into the following fractions: >16 mm, 8-16 mm, 2-8 mm, 0.2-2 mm, <0.2 mm and a fraction that floated on top of the slurry before the final separation phase, composed of organic matter (OM). Analysis of total concentrations of contaminants in all soil fractions indicated that wet sieving/soil washing was not efficient to reduce the total volume of soil that needs further treatment. Even the coarsest soil fractions (>8 mm) contained elevated concentrations of total As and PAH. Leaching of As from all washed soil fractions was so high, that none of the particle size fractions could be disposed of without additional treatment., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Determining the fate of preservatives in commercial wood products is essential to minimize their losses and improve protective impregnation techniques. The fate of triazole fungicides in ponderosa pine wood was investigated in both outdoor and controlled-environment experiments using a representative triazole, tebuconazole (TAZ), which was accompanied by propiconazole (PAZ) in selected experiments. The study was designed to mimic industrial settings used in window frame manufacturing. To investigate the TAZ fate in detail, loosely and strongly bound fractions were differentiated using a multi-step extraction. The loosely bound TAZ fraction extracted through two sonications accounted for 85± 5% of the total TAZ, while the strongly bound TAZ was extracted only with an exhaustive Soxhlet extraction and corresponded to the remaining 15± 5%. A significant fraction (∼80%) of the original TAZ remained in the wood despite a six-month exposure to harsh environmental conditions, maintaining wood preservation and assuring minimal environmental impact. Depletion of loosely bound TAZ was observed from cross-sectional surfaces when exposed to rain, high humidity and sunlight. Water leaching was deemed to be the major route leading to triazole losses from wood. Leaching rate was found to be slightly higher for TAZ than for PAZ. The contribution of bio-, photo- and thermal degradation of triazoles was negligible as both PAZ and TAZ sorbed in wood remained intact. Triazole evaporation was also found to be minor at the moderate temperature (20-25 °C) recorded throughout the outdoor study., (Copyright © 2017 Elsevier Ltd. All rights reserved.)