Photocatalytic CO₂ reduction can convert CO₂ into fuels or high-value-added chemicals,but slow reaction kinetics,high carrier recombination rates,and limited surface reactions at room temperature hinder its practical application.In recent years,researchers have begun introducing thermal energy to form photothermal catalysis,which significantly enhances reaction rates and product selectivity,becoming an important direction to overcome the limitations of traditional photocatalysis.However,the concept of photothermal catalysis is overly complex and hard to understand.To address this issue,this paper proposes to use temperature as standard and classify the photothermal catalysis into high temperature,medium temperature and low temperature (room temperature) photocatalysis.On this basis,the origin,fundamental theory,material systems,and applications of high-temperature photocatalysis in CO₂ photoreduction and other fields are summarized.Emphasis is placed on describing the modulation mechanisms of temperature on semiconductor band structures,charge carrier behaviors,and surface reaction kinetics,and the advantages and disadvantages of two types of high-temperature photocatalytic systems based on wide-bandgap semiconductors and localized plasmonic effects are compared.

The efficient removal of methane from industrial mixed gases is not only an environmental imperative to mitigate its potent greenhouse effect,but also a critical challenge in achieving high-value utilization of industrial gases.It represents a pivotal step in driving the green and low-carbon transformation of sectors such as chemicals and energy.Currently,primary methods for methane removal from industrial gases include cryogenic separation,membrane separation,catalytic oxidation,and adsorption.Each methane removal technology possesses distinct characteristics.Cryogenic separation utilizes low temperatures to separate methane from other gases,being suitable for high-concentration methane recovery,yet involving complex equipment and high energy consumption;membrane separation excels in low-concentration methane separation through selective permeability,yet suffers from high membrane material costs and short service life;catalytic oxidation promotes methane oxidation efficiently with low energy consumption,though catalyst stability,cost,and resistance to poisoning require improvement;adsorption methods utilize selective adsorbents,being suitable for low-concentration methane with low cost,though adsorbent capacity is limited and regeneration energy consumption is high.When selecting specific methane removal methods for practical industrial applications,comprehensive consideration must be given to factors including gas composition,methane concentration,cost,and environmental impact.By systematically reviewing the principles and research progress of methane removal technologies and analyzing their development trends,this will facilitate the advancement of resource utilization for methane and industrial gases.

Developing efficient and low-cost adsorbent materials to remove heavy metals,dyes,and other characteristic pollutants from water is currently a key focus in water treatment research.Biochar with low raw material costs,wide availability,and abundant functional groups,are considered to be ideal materials for water treatment.Modifying biochar with nanomaterials such as nano-metal oxides can significantly enhance its adsorption performance.This paper first introduces the physicochemical properties of biochar,then elaborates on the characteristics of composite biochar materials based on different modification methods.Their applications in the adsorption and degradation of pollutants such as heavy metals,dyes,and phenols in water depending on practical scenarios are summarized.Finally,the recycling and reuse strategies for composite biochar materials are discussed,along with an outlook on future research directions.

Conventional separation methods for methanol systems (such as distillation,extraction,and adsorption) suffer from high energy consumption,serious pollution,and low efficiency,which do not align with the national requirements for green and low-carbon development in the chemical industry.Membrane separation can overcome the limitations of methanol azeotropic systems and can be applied efficiently and with low energy consumption.This article focuses on the application of membrane separation technology in methanol systems.Pervaporation membranes achieve separation based on differences in the solution-diffusion coefficients of components in the membrane material,mainly applied in methanol-water,methanol-methyl tert-butyl ether,and methanol-dimethyl carbonate systems.In addition,membrane separation has certain requirements regarding the methanol concentration in the liquid to be separated,and using membrane separation alone cannot meet the needs of industrial separation.Coupling membrane separation with conventional separation methods,such as distillation and crystallization,combines the wide applicability of traditional separation with the low energy consumption of membrane separation.This hybrid technology has been successfully applied in the separation of methanol-water and methanol-dimethyl carbonate systems.

Ammonia internal combustion engines (ICEs) have emerged as one of the important research directions in the transportation sector due to their zero-carbon emission potential.However,their exhaust gases contain significant amounts of nitrogen oxides (NO_x),unburned ammonia (NH₃),and a certain concentration of nitrous oxide (N₂O),necessitating the improvement of catalyst performance for the synergistic conversion of NO_x and N₂O.In this work,a series of Fe-based zeolite catalysts were prepared via the incipient wetness impregnation method,and we investigated the influence of Fe-based catalysts supported on beta zeolites with different Si/Al ratios (SAR) on the simultaneous catalytic conversion performance of NO_x and N₂O in the aftertreatment of ammonia ICEs.A series of characterizations,including XRD,N₂ adsorption-desorption isotherms,SEM,UV-vis DRS,and NH₃-TPD,were employed to analyze the textural properties,morphology,Fe species,and surface acidity of the catalysts.The results show that the beta zeolite with SAR=24 exhibits the smallest particle size,and partial stacking and agglomeration form mesopores,which is more conducive to the adsorption of reactants.Meanwhile,the Fe/beta-24 catalyst contains more Brønsted acid sites,which can further promote the adsorption and activation of NO_x and N₂O.In addition,the Fe species in the Fe/beta-24 catalyst mainly exist in the form of isolated Fe ions and FeO_x clusters,which are the main active species for the conversion of NO_x and N₂O.Therefore,under severe simulated ammonia ICE exhaust conditions,the Fe/beta-24 catalyst exhibits the optimal capability for the synergistic conversion of NO_x and N₂O.This work provides a new research strategy for the synergistic abatement of NO_x and N₂O in the aftertreatment system of ammonia ICEs.

Heavy and low-quality feedstocks increase mechanical and soluble impurities in fixed-bed hydrotreating catalysts.These impurities cause high pressure drop,pore blockage,and catalyst deactivation.This study investigates how catalyst geometry affects impurity deposition and catalyst stability.We introduce the particle volume-to-surface area ratio (V/S) as an equivalent geometric parameter.It quantifies the combined effects of particle size and shape.Experiments were conducted using cold-model tests and micro fixed-bed hydrotreating reactors under conditions representative of industrial operations.Results show that V/S strongly controls impurity distribution along the bed.It also affects pressure drop development and catalyst activity retention.Catalysts with high V/S in the inlet zone leads impurities penetrating deep into the bed layer.Catalysts with low V/S leads the concentrated deposition of impurities at the top of the bed layer and limits impurity migration to deeper bed regions.Hydrogenation results in fixed bed show that denitrification activity decrease caused by soluble impurities also adjusted by V/S.Catalysts with low V/S exhibit a higher activity retention rate.Under conditions of similar V/S,particle shape further adjusts impurity interception.Complex shapes perturb local flow and increase solid-fluid contact probability to intercept impurities.The use of V/S as a unified geometric parameter provides a quantitative basis for selecting catalyst type and arranging bed layout.Overall,this work offers a practical guideline for improving the operational lifetime and efficiency of industrial hydrotreating units.

This study investigates the selective hydrogenation of acetone to isopropanol in benzene-acetone mixture.A series of supported catalysts,including Cu/SiO₂,Fe/SiO₂,Cr/SiO₂,and Zr/SiO₂,were prepared using the deposition-precipitation method.These catalysts were characterized by XRD,FT-IR,TEM,H₂-TPR,and XPS,and their performance was evaluated in a fixed-bed reactor.The results indicate that the Cu/SiO₂ catalyst exhibits superior catalytic performance.Over the 2%Cu/SiO₂ (mass fraction) catalyst,under reaction temperature of 130-170 ℃,pressure of 2.0 MPa,and a weight hourly space velocity (WHSV) of 1.0 h^-1,the acetone conversion exceeded 98%,with 100% selectivity to isopropanol.Notably,no hydrogenation of benzene occurred during the process.The catalyst demonstrated stable catalytic activity,achieving efficient and highly selective hydrogenation of acetone in the presence of benzene.

Nanoscale HZSM-5 zeolite catalysts were synthesized via hydrothermal crystallization,and used in one-step gas-phase synthesis of isoprene from isobutylene and formaldehyde.The mechanism of isoprene synthesis was investigated based on these catalysts.Characterizations including Py-IR,NH₃-TPD,XRD,and TG of the catalysts,combined with experimental evaluation results,indicate that only moderately strong Lewis acid (L acid) sites serve as the active centers for this reaction.Strong acid sites act as the active centers for byproduct formation and are prone to coking.

Photocatalytic oxidative coupling of methane (OCM) represents an important pathway for high-value methane utilization under mild conditions.However,the structure-performance relationships between catalyst architecture and catalytic activity require further investigation.In this study,four distinct morphologies of Au nanoparticles (cubic,rod-shaped,rhombic,and sheet-like) were synthesized via a seed-mediated growth method and subsequently loaded onto commercial ZnO to examine the effects of Au morphology and size on photocatalytic OCM performance.The results demonstrate that rod-shaped Au (67 nm×36 nm) exhibits optimal catalytic performance,achieving methane conversion of 61.33 μmol/(g·h) and C_2⁺ selectivity of 84.21%,representing improvements of 63% and 13%,respectively,compared to the poorest-performing cubic Au.Photoluminescence (PL) spectroscopy reveals that rod-shaped Au possesses the highest charge carrier separation efficiency,which is identified as a key factor contributing to its superior catalytic performance.Furthermore,when the size of rhombic Au increases from 74 nm to 214 nm,the conversion decreases by 34.2% while C_2⁺ selectivity drops from 70.14% to 51.60%.In contrast,although the conversion of rod-shaped Au decreases by 22.7% as its size increases from 67 nm to 215 nm,the selectivity remains about 80%,indicating a synergistic effect between Au morphology and size on product selectivity.This study elucidates the structure-performance relationships between Au morphology and catalytic activity,providing scientific guidance for the rational design of key components in photocatalytic methane conversion catalysts.

Supported Pt-Li₂O/Al₂O₃ and Co-Li₂O/Al₂O₃ catalysts were prepared by the equal-volume stepwise impregnation method using Pt and Co as active components,Li₂O as additive,and γ-Al₂O₃ as carrier.The catalysts were used in steam reforming of glycerol to hydrogen,and the effects of reaction temperature,water-to-alcohol ratio,and glycerol liquid space velocity for the hydrogen production process were investigated.The Pt-Li₂O/Al₂O₃ and Co-Li₂O/Al₂O₃ catalysts phase,specific surface area,carbon deposition were characterized by techniques such as XRD,N₂ adsorption-desorption,and TPR.Results indicated that Pt-Li₂O/Al₂O₃ catalyst with a large specific surface area and average pore radius was more effective for steam reforming glycerol to hydrogen.The hydrogen yield could reach 5.97 mol/mol.

Tetraethylthiuram disulfide (TETD) was prepared by a two-step method including condensation and oxidation reaction in one reactor using n-butanol as solvent,effectively shortening the process steps and improving the yield of the target product.The obtained yellow powder was analyzed and detected by FT-IR,XRD,UV-vis,HPLC,¹H-NMR and ¹³C-NMR.The characterization results show that the microscopic structure of product contains ethyl,C=S,C—N,C—C,C—S,S—S,etc.The structure is very complex with large molecular steric hindrance.N has a stable tertiary amine structure and does not produce nitrosamines.Hydrogen atom number is 20 and carbon atom number is 10.The product was identical to the molecular formula C₁₀H₂₀N₂S₄ of TETD.When the materials were fed according to n(n-butanol)∶n(ethylamine)∶n(carbon disulfide)∶n(hydrogen peroxide)=3∶1∶1∶2,condensation temperature of 30~40 ℃,condensation time of 2 h,oxidation temperature of 20 ℃,oxidation time of 1 h,atmospheric pressure,the yield and purity of TETD was 90.2%,97.61%,respectively.The two-step method is in line with clean production,and lay foundation for the integration of technology,industry and applications.

Iron sludge collected from the iron removal filters was used as raw material to prepare an iron sludge-based catalyst through drying,grinding,and thermal treatment at 600 ℃.The catalyst was utilized to activate peroxymonosulfate (PMS) for degrading tetracycline (TC) in aqueous solution.Structural characterization was conducted via SEM,EDS,XRD,and VSM,and the results revealed that the catalyst was predominantly consisted of amorphous iron oxides and exhibited promising magnetic separation performance with a saturation magnetization of 2.57 emu/g.The degradation kinetics of TC in this system fitted to the pseudo-first-order model.Under the conditions of 0.5×10^-3 mol/L PMS,0.1 g/L catalyst and initial pH=7,a removal efficiency of 94.40% for TC was achieved.Quenching experiments and electron paramagnetic resonance (EPR) analysis indicated that hydroxyl radicals (·OH),sulfate radicals (${SO}_{4}^{-}$·),and singlet oxygen (¹O₂) served as the primary reactive oxygen species in the degradation process,with free radicals contributing slightly more significantly than singlet oxygen.This research provides a valuable technology for the resource utilization of iron sludge and the effective elimination of recalcitrant organic pollutants.

In order to solve the limitations of the desulfurization performance of single metal oxide modified activated carbon and prepare high-efficiency hydrogen sulfide adsorbent,coal-based activated carbon was used as a carrier and an equal-volume impregnation method combined with a nitrogen-protected roasting process was used to prepare an iron-copper oxide synergistically modified adsorbent.The influence of preparation factors such as iron-copper ratio,impregnation concentration,roasting temperature and water film moisture content was explored.The structure and chemical properties were characterized through N₂ adsorption-desorption,XRD,XPS and other technologies,and the desulfurization performance was evaluated under industrial working conditions of 0-40 ℃ and 1 500-4 200 h^-1.The results show that the optimal preparation parameters are iron-copper mass ratio of 1∶2,impregnation concentration of 20%,roasting temperature of 400 ℃,and water film moisture content of 10%.The adsorption capacity of adsorbent prepared at the optimized conditions reaches 48.5 mg/g and the penetration time is 2 100 min.This adsorbent synergistically improves the desulfurization effect through multiple mechanisms such as Fe³⁺ catalysis,Cu²⁺ adsorption enhancement,and 1-5 nm micropore mass transfer.It is suitable for the removal of low-concentration hydrogen sulfide in scenarios such as petrochemical industry and biogas utilization.