Photocatalysis is a green, mild, efficient and promising advanced oxidation technology. Lignin biomass, as a natural aromatic biomass resource, is difficult to be effectively utilized due to its complex structure, resulting in a huge waste of biomass resources. Utilizing photocatalytic technology to depolymerize lignin into small molecular aromatic compounds is a new way for economic, green and sustainable high-value utilization of biomass resources. MgIn2S4, as a ternary metal sulfide based on indium, has advantages such as visible light responsiveness, tunable structure and chemical stability. However, the carrier recombination rate of a single MgIn2S4 photocatalyst is relatively high, requiring optimization and modification. In this paper, by using carbon quantum dots as a co-catalyst and adopting the strategy of constructing heterojunction loading, the photocatalytic performance of MgIn2S4 was optimized. Firstly, a series of binary heterojunction Nb2O5/MgIn2S4 (named yN/MIS, where y is the molar ratio of Nb to Mg) photocatalysts were prepared, and the optimal composite ratio of Nb/Mg was determined to be 0.25 through photocatalytic performance tests. Then, a series of ternary heterojunction Nb2O5/ N-CQDs/MgIn2S4 (named 0.25 N/zC/MIS, where z is the loading amount of N-CQDs) photocatalysts were prepared. The results of photocatalytic performance tests confirmed that the optimal loading amount of N-CQDs was 0.4%. The optimized photocatalyst could degrade 77.8% of sodium lignin sulfonate (SLS) within 150 min. After three consecutive photocatalytic cycles, the degradation rate of SLS by the 0.25 N/0.4%C/MIS composite material remained at 74.2%, and the crystal structure of the 0.25 N/0.4%C/MIS composite material did not undergo any significant changes after three consecutive photocatalytic cycle tests. This result can prove that the crystal structure of the 0.25 N/0.4%C/MIS composite material is relatively stable. The decomposition products were analyzed by GC-MS tests. By comparing the total ion current graph with the NIST database, it can be known that the main products of photocatalytic decomposition include aromatic hydrocarbons, benzyl alcohol, phenols and phthalates, etc.

Membrane distillation (MD) was a promising approach for treating highly concentrated ammonia-nitrogen wastewater. However, membrane wetting often limited large-scale application. To address this, we built an anti-wetting layer on a commercial PVDF membrane surface by coating fluoride and depositing SiO2 nanoparticles. Three PVDF/ SiO2/F membranes were prepared with different silicon contents: 1%, 6%, and 12% (volume) of tetraethyl orthosilicate (TEOS). These processes created different surface roughness on the modified membranes. Results showed that the membrane containing 6% TEOS exhibited the best resistance to sodium dodecyl sulfate (SDS) in NaCl solution. This optimized membrane was subsequently tested with real wastewater, including source-separated urine and landfill leachate. In 10 h, it removed 97.5% of total organic carbon (TOC) from urine, achieving an ammonia absorption rate of 55.1% and removed 92.4% from leachate, with an ammonia absorption rate of 37.58%. These results provide a reference for membrane fabrication parameter optimization to enhance the membrane's anti-wetting ability.

In this study, nitrogen doped carbon quantum dots (NLCQDs) were synthesized by hydrothermal method using alkaline lignin as the carbon source and ethylenediamine as the nitrogen source. Subsequently, a BiOCl/WO3 heterojunction was constructed through a solvothermal approach. By optimizing the molar mass ratio of BiOCl to WO3, BiOCl/WO3-2 composite (BiOCl: WO3 = 5:1) was proved to possess the best catalytic activity. When BiOCl, WO3 and NLCQDs jointly construct the ternary composite catalytic system BiOCl/WO3-2/NLCQDs-Z (Z is the loading amount of NLCQDs, Z = 5, 10, 15 mL), the catalytic activity is significantly improved. Using CO yield as the indicator, BiOCl/WO3-2/NLCQDs-10 was determined to have the best photocatalytic activity. TEM and XPS measurements show that a Z-type heterojunction is formed between BiOCl and WO3, and a built-in electric field is established at the interface. BiOCl/WO3-2/NLCQDs-10 maintained stable catalytic activity for CO2 reduction within 3 h, with a final CO yield of 47.02 mu mol center dot g- 1 center dot h- 1, which was 13.3 and 4.2 times higher than BiOCl and BiOCl/WO3-2, respectively. In this study, the separation and transfer path of photo-generated charge were optimized by reasonably constructing BiOCl composite catalytic system, and the photocatalytic performance of CO2 reduction was significantly improved.

Research on the removal of sulfur-containing malodorous gases from air via biochar adsorption demonstrates significant application potential. In this study, silicon-modified graphitized carbon was synthesized through pyrolysis using peanut shells, rice husks, and walnut shells as precursors. Among the resulting materials, rice husk-derived biochar (DK-700-5) and walnut shell-derived biochar (HT-800-10) exhibited pronounced targeted adsorption toward CH3SH and H2S, respectively. The sulfur adsorption capacity of DK-700-5 was 8.3 times higher than that of unmodified rice husk biochar, while HT-800-10 achieved a 2.45-fold enhancement in H2S adsorption compared to its unmodified counterpart. Carboxyl and oxygen vacancies on DK-700-5 were identified as critical for CH3SH adsorption, facilitating its immobilization and gradual oxidation to sulfate (SO42-), with intermediate sulfur species such as R-SO-R, S0, and C-S detected. In parallel, HT-800-10 adsorbed and oxidized H2S through its porous structure and surface superoxide radicals, converting it into elemental sulfur (S0) and sulfate (SO42-), thereby achieving efficient adsorption and oxidative transformation.

Persistent free radicals (PFRs) in biochar have emerged as a research focus in environmental remediation due to their high efficiency in pollutant degradation. Biochar serves as an ideal matrix for generating PFRs, showing significant potential for treating industrial wastewater and exhaust gases. This review systematically examines the critical factors influencing PFR generation in biochar, including feedstock type (lignocellulosic vs non-lignocellulosic), pyrolysis temperature range (200–700°C), and hydrothermal carboniza­tion conditions. The mechanisms of PFR-mediated contaminant transformation via generation of reactive oxygen species (ROS) are elucidated, demonstrating effectiveness against diverse pollutants such as organo­chlorides (e.g., polychlorinated biphenyls), variable-valence metals [e.g., Cr(VI), As(III)], sulfonamide antibiotics (e.g., sulfamethazine), and reduced sulfur compounds (e.g., hydrogen sulfide). To address current challenges like the low concentration of PFRs in typical biochars and incomplete understanding of ROS activation pathways, future research should prioritize the development of targeted strategies to enhance the ROS generation efficiency of biochar-derived PFRs. This review aims to provide a theoretical foundation for the green and high-value application of biochar-based materials.

By coupling Mn0.5Cd0.5S with NiCo2S4 to form a heterojunction, the photocatalytic performance is enhanced. Subsequently, CQDs are introduced to construct a ternary heterojunction. Using alkali lignin as the carbon source, lignin carbon quantum dots (CQDs) were prepared via the hydrothermal method, while NiCo2S4 bimetallic sulfide with a unique nano-eggshell spherical structure was prepared via a solvothermal approach. Based on these materials, a series of CQDs/NiCo2S4/Mn0.5Cd0.5S Z-scheme heterojunction photocatalysts with varying mass ratios were constructed. The introduction of either NiCo2S4 or CQDs individually could enhance the photocatalytic activity of Mn0.5Cd0.5S, while the synergistic integration of all three components resulted in a more pronounced enhancement effect. Among these, the 20C/8%NCS/MCS composite exhibited the highest photocatalytic hydrogen evolution rate, reaching 22.72 mmol·g-1·h-1. This work provides important structural and mechanistic insights for the design of highly efficient and stable multicomposite photocatalytic systems.

In this study, lignin-based carbon quantum dots (CQDs) were prepared by a one-step hydrothermal method using alkaline lignin as the carbon source and then further combined with ZnIn2S4 photocatalyst to construct a series of CQDs-X/ZnIn2S4 composite photocatalyst. The experimental results indicated that when the loading amount of CQDs was 20 mL, the composite material exhibited the best photocatalytic hydrogen production performance. Structural characterization revealed that CQDs with a size of 4–6 nm were successfully modified on the surface of flower-like ZnIn2S4 photocatalyst microspheres assembled by nanosheets, forming a tight heterostructure. Optical and electrochemical tests confirmed that the introduction of CQDs effectively broadened the light absorption range, adjusted the band structure and significantly promoted the separation and transfer of photogenerated carriers, while reducing the charge recombination rate. In addition, compared with pure ZnIn2S4 (48.18 m2·g−1), CQDs-20/ZnIn2S4 has a relatively larger specific surface of 79.33 m2·g−1, providing more active sites. This study demonstrated that the composite strategy based on lignin CQDs could significantly enhance the photocatalytic performance of ZnIn2S4 photocatalyst, providing an effective approach for the high-value utilization of lignin and solar hydrogen production.

In order to explore the effect of agricultural film doping on the structure and adsorption properties of straw biochar materials, the graphitized biochar of SPS600-B was prepared using waste corn straw mixed with polyethylene agricultural film as raw materials and anhydrous potassium carbonate as modifier. The material was characterized by SEM, TEM, BET, XRD and elemental analysis. The adsorption performance and mechanism for methylene blue(MB) by SPS600-B were investigated. The results showed that SPS600-B was highly graphitized with many non-penetrating pore and carbon microsphere structures on its surface, and the specific surface area was 821.96 m2/g. At 25 ℃ and pH=7, the removal rate of 100 mg/L MB by 0.2 g/L SPS600-B reached 93.2%, and the adsorption capacity was 466.2 mg/g. After 5 cycles of adsorption-desorption recycling, the removal rate of MB could still reach 79.4%. The adsorption mechanism revealed that the adsorption process conformed to the quasi-second-order kinetic model and Langmuir model, which was dominated by chemisorption. The adsorption process was affected by pore adsorption, electrostatic attraction, π-π electron interaction and hydrogen bonding. The adsorption behaviour was a spontaneous adsorption reaction.

In this paper, direct Z-type BiPO4/Bi2WO6 heterojunctions were successfully prepared by a two-step solvothermal method using bismuth nitrate, disodium hydrogen phosphate, and sodium tungstate as precursors. The photocatalytic degradation capabilities of the composites for the antibiotic ciprofloxacin (CIP) were examined in circumstances that mimicked sunlight. The composites all showed high adsorption-catalytic properties compared with the monomer materials. Among them, 10 wt

In this study, copper-modified nanocarbon composites (OMC) were successfully prepared using two-dimensional carbon nanosheets as the material substrate, the low-temperature hydrothermal method as the main process, and copper nitrate as the modifier. The effects of the modifier dosage ratio, hydrothermal temperature, and residence time on the structure and hydrogen sulfide (H2S) adsorption performance of OMC were investigated. The results show that the OMC with persistent free radicals and copper oxides prepared under the conditions of a mass ratio of copper nitrate to two-dimensional carbon nanosheets of 2, a hydrothermal temperature of 130 °C, and a time of 8 h, respectively, has the best adsorption performance for H2S, with an adsorption sulfur capacity of up to 46.72 mg/g. The excellent adsorption and removal capacity of the OMC for H2S are attributed to two reasons. First, the addition of copper during the hydrothermal process promotes the generation of persistent free radicals on the surface of OMC, enhancing its oxidation capacity for H2S. Second, the copper oxide loaded on the surface of OMC also has a good adsorption capacity for H2S. The synergistic effect of persistent free radicals and copper oxides converts H2S into solid products such as sulfides, elemental sulfur, sulfites, and sulfates. This work not only achieved the goal of low-temperature preparation of nanocarbon composites but also expanded the application of persistent free radicals in pollutant control.

In this study, chitosan was first used as the raw material for filmmaking, and the film-forming conditions were optimized to prepare six kinds of chitosan-based membranes, and then charcoal composite membrane materials were prepared by adding different amounts of lignin charcoal to fill in the base membranes; the adsorption performance of the composite membrane was analyzed using H2S as the target, and the mechanical properties and structure of the composite membrane were explored using various testing techniques. The experimental results showed that the chitosan-based membrane could adsorb a certain amount of H2S due to its hydroxyl-rich surface. When lignin carbon was added to it, and with the increase of the content of lignin carbon, the performance of the membrane adsorption of H2S was improved, but the mechanical properties decreased, and in a comprehensive comparison of the adsorption performance and mechanical properties of the composite membrane, which had a better adsorption length of H2S adsorption of 84 min and the tensile strength of 1.65 MPa. The pore structure in the composite membrane due to microphase separation and the exposure of oxygen-containing functional groups on the surface of the base membrane and charcoal were the main reasons for the effective retention of H2S.

Short-chain fatty acids (SCFAs) production was limited by low organic matters solubilization and methanogens rapid consumption during sludge anaerobic fermentation. The HA/Fe(II)/PAA pretreatment system was employed to solve these issues in this study. Results showed that HA/Fe(II)/PAA pretreatment significantly enhanced the disintegration of sludge cells and EPS, improved the dissolution of organic matter and the biodegradability of sludge, thereby promoting the production of SCFAs. The optimal SCFAs production achieved with HA/Fe(II)/PAA pretreatment was 2527.62 mg COD/L, approximately 5.14 times that of the blank group, with acetic acid accounting for 64.94 %. Further research indicated that for HA/Fe(II)/PAA system, the introduction of HA can accelerate Fe(II)/Fe(III) cycle, and promote the production of active species, as center dot OH, R-O center dot, and FeIVO2+. Moreover, HA/Fe(II)/PAA pretreatment significantly increased the activity of hydrolysis and acidification enzymes and inhibited the activity of methanogenic enzymes. Meanwhile, the microbial community analyses further confirmed that HA/Fe(II)/PAA can enrich the SCFAs-forming microorganisms and inhibit SCFAs-consuming microorganisms. All of these factors were conducive to the accumulation of SCFAs. This study demonstrated that HA/Fe(II)/PAA pretreatment can effectively promote high-level SCFAs production, providing new insights for high-value resource recovery from sludge.

Crop straw is a kind of renewable resource with great application potential, which has the characteristics of a wide source, abundant reserves and low price. Using straw as a raw material and a hydrothermal process to prepare high-function carbon-based material, it is an economic and green way to promote straw resource utilization. In this article, the influencing factors in the preparation process of straw hydrothermal carbon were reviewed. The influences of process parameters such as straw carbon source, hydrothermal time, hydrothermal temperature and solid–liquid ratio on the structural properties of hydrothermal carbon were emphasized. The regulation of the morphology and structure of carbon by activators such as KOH and KMnO4 were analysed. At the same time, the application of straw-based hydrothermal carbon in the field of environmental pollution control, catalysis and electrochemistry is summarized. Finally, it is pointed out that the future research should focus on the structure control method, green activation technology of straw-based hydrothermal carbon and the preparation of hydrothermal carbon from mixed straw, and further improve the stability of the porous structure of the hydrothermal carbon and the interference-free in the practical application environment, so as to realize the commercial application of straw-based hydrothermal carbon.

Methylene blue is a significant pollutant that seriously threatens the safety of water environments, and traditional methods have difficulty removing it. In this study, lignin carbon quantum dots (CQDs) were prepared by the hydrothermal method, and a BiVO4/CQD composite material was fabricated for the photocatalytic degradation of methylene blue. Through various testing methods, the optimal composite with carbon quantum dots was successfully studied. The incorporation of carbon quantum dots reduced the band gap of BiVO4 and enhanced the light absorption and electron transfer ability of the BiVO4/CQD composite material. The incorporation of CQDs can effectively enhance the degradation performance of BiVO4/CQD composite material toward methylene blue. Under illumination for 120 min, the degradation rate of methylene blue by pure BiVO4 material was only 56.2

Lignin quantum carbon dots (CQDs) were prepared using basic lignin as the carbon source. They were loaded onto Z-type ZnIn2S4/WO3 heterojunction semiconductor materials by a one-step hydrothermal method to construct a ternary composite photocatalyst. Taking the photocatalytic water hydrogen evolution reaction performance as an indicator, it was found that the 33

This study used alkaline lignin as the carbon source for preparing alkaline lignin carbon quantum dots (LCQDs) based on the solvothermal method. To achieve efficient photocatalytic degradation of tetracyclic hydrochloride antibiotics (TCH), hydrangea-shaped LCQDs/Bi2MoO6 composites were prepared in situ by the solvothermal method exploiting the optical properties of LCQDs. The composite material was systematically characterized using XRD, FTIR, XPS, SEM, TEM, EIS, nitrogen adsorption-desorption testing, and UV-vis DRS to determine its crystal structure, microstructure, and optoelectronic properties. The results show that the sample has high purity and good crystallinity. The experiment on photocatalytic degradation further demonstrated that the LCQDs/ Bi2MoO6 composite material modified with LCQDs exhibited superior photocatalytic activity compared to a single Bi2MoO6. Among them, BMO/LCQDs-7 showed the best effect. After 120 min of illumination, the rate of TCH removal through photocatalysis was 98.76%, with a degradation rate constant: K= 0.026 min-1. After five cycles, the removal rate of TCH can still be maintained at 79.35%. The photocatalytic degradation of TCH has been demonstrated through EPR and LC-MS experiments primarily caused by h+ and & sdot;O2- .

BACKGROUND: Graphite-like biochar of NWSC600K was prepared at 900 degrees C using walnut shell as the raw material and aqueous ammonia (NH3 center dot H2O) as an activator, and characterized using transmission and scanning eletron microscopy (TEM, SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Raman spectroscopy and Fourier transform infrared (FTIR). The study investigated the adsorption performance and mechanism of NWSC600K for ciprofloxacin (CIP). RESULTS: The results showed that extremely tiny pores were found on the surface of NWSC600K, which increased its specific surface area to 823.91 m(2) g(-1), whereas the average pore size of NWSC600K decreased to 3.23 nm. The results of TEM, XRD and Raman spectroscopy detected well-arranged lattice stripes as well as characteristic peaks corresponding to the graphite lattice appearing on the surface of NWSC600K. Moreover, the I-D/I-G value for NWSC600K was 1.429. The FTIR results showed that functional groups including the amino group were formed on NWSC600K. CONCLUSION: The adsorption capacity of NWSC600K for CIP was 158.14 mg g(-1) and the corresponding removal rate was 97.5% at pH 7. The pH value impact on the removal efficiency of CIP greatly, and the removal rate of CIP decreased linearly with increasing pH. The coexisting ions also would inhibit the adsorption of CIP on NWSC600K. Results obtained from kinetic and isotherm models, thermodynamics and characterization analyses suggested that pore-filling, pi-pi stacking, hydrogen bonding, hydrophobicity and electrostatic interaction existed during the adsorption process. The adsorption was a nonspontaneous exothermic reaction. (c) 2024 Society of Chemical Industry (SCI).

In this paper, the modified lignin drug carrier materials with targeted slow release effect were studied. 0.2 g of alkali lignin was added to 20 mL of acetylation reagent (the ratio of acetyl bromide to acetic acid is 8:92) at 50 °C, sealed and stirred for 3 h for acetylation reaction, rotary evaporation for 30 min, drying to a fixed weight, to obtain acetylated lignin, recorded as ACAL. Dissolve 2.0 mg of ACAL in 10 mL of 99.5

Carbon nanomaterials are widely used in the treatment of water pollutants because of their structural characteristics such as large specific surface area， complex pore structure， and rich surface functional groups. This paper summarized the carbon sources and preparation methods of nanocarbon materials， analyzed the principles and influencing factors of nanostructure regulation of carbon materials， reviewed the research progress in nanocarbon adsorption of toxic pollutants in water， and put forward the bottlenecks that need to be broken through for the future industrial application of nanocarbon materials. Hydrothermal， pyrolysis and chemical vapor deposition are the common methods for the preparation of nanocarbon， and traditional carbon sources， such as sugars， petrochemicals， and biomass， can be used to obtain nanostructured carbon through the modulation of parameters such as preparation temperature and activator. Carbon nanotubes， carbon nanospheres， and nanoporous carbon have been developed for better contact with pollutants， thus exhibiting significant adsorption advantages for toxic pollutants such as phenols， benzenes， dyes， antibiotics， and heavy metal ions. In order to realize the wide application of nanocarbon adsorbent materials， further research is required to be carried out in the future on the development of green and efficient preparation process of nanocarbon， the exploration of the formation and evolution law of carbon structures， the design of macroscopic use scheme of nanocarbon， and the development of nanocarbon based composite materials.

Straw, as a kind of biomass waste, has the advantages of low cost and abundant storage, which makes it a promising renewable resource. Using rice straw as a carbon source, carbon nanosheets were prepared by a two-step carbonization method combining low-temperature pyrolysis and low-temperature hydrothermal, and they were used as H2S removal agents. The results showed that during the two-step carbonization process, the adsorption performance of carbon nanosheets for H2S showed a tendency of enhancing and then weakening with the increase of pyrolysis temperature in the first step, and the sulfur capacity could reach 3.1 mg/g at the maximum of the pyrolysis temperature of 200 degrees C, which was superior to or close to that of the modified or activated carbon. The XPS, EPR, and CO2-TPD tests showed that the surface of carbon nanosheets was alkaline, containing a large number of hydroxyl groups and the presence of phenoxy persistent free radicals or semiquinone persistent free radicals. It was analyzed that the direct or indirect oxidation of H2S by the persistent radicals under an alkaline environment could convert the -2-valent sulfur into -1-, 0- and +6-valent sulfur to realize the adsorption and removal of H2S. This work, while offering the possibility of utilizing carbon nanosheets made from straw as a material for H2S adsorption and removal, also expands the application of straw waste in exhaust gas treatment.