Recent advances in catalytic systems for CO_(2) conversion to substitute natural gas(SNG):Perspective and challenges

It has been well established that carbon dioxide(CO_(2))is one of the main greenhouse gasses and a leading driver of climate change.The chemical conversion of CO_(2) to substitute natural gas(SNG)in the presence of renewable hydrogen is one of the most promising solutions by a well-known process called CO_(2) methanation.There have been comprehensive efforts in developing effective and efficient CO_(2) methanation catalytic systems.However,the choice of competitive and stable catalysts is still a monumental obstruction and a great challenge towards the commercialization and industrialization of CO_(2) methanation.It is necessary to emphasize the critical understandings of intrinsic and extrinsic interactions of catalyst components(active metal,support,promoter,etc.)for enhanced catalytic performance and stability during CO_(2) methanation.This study reviews the up-to-date developments on CO_(2) methanation catalysts and the optimal synergistic relationship between active metals,support,and promoters during the catalytic activity.The existing catalysts and their novel properties for enhanced CO_(2) methanation were elucidated using the state-of-the-art experimental and theoretical techniques.The selection of an appropriate synthesis method,catalytic activity for CO_(2) methanation,deactivation of the catalysts,and reaction mechanisms studies,have been explicitly compared and explained.Therefore,future efforts should be directed towards the sustainable developments of catalytic configurations for successful industrial applications of CO_(2) utilization to SNG using CO_(2) methanation.

Carboxylation of Aromatics by CO₂under “Si/Al Based Frustrated Lewis Pairs” Catalytic System

Carboxylation of aromatics by CO2 to generate corresponding carboxylic acids is recently providing a novel approach to utilize the green gas CO2, in which the activation of CO2 is the key procedure. Among the many catalytic systems employed in the carboxylation, the concept of “Frustrated Lewis Pairs” (FLPs) was scarcely mentioned, which perform excellently in activating small molecules like CO2. The FLPs are combinations of Lewis acids and Lewis bases which failed to form adducts due to their bulky steric congestion. In this paper, we first attempted various Si/Al Based FLPs to catalyze the carboxylation of aromatics through the activation of CO2, and a good yield of 62% - 97% was obtained. The reaction mechanism was proposed, involving the activation of CO2 mainly contributed by AlCl3 in cooperation with organosilane, forming an intermediate consisting of CO2, AlCl3, and R4Si, as well as the subsequent electrophilic attack to aromatics, thus to promote the carboxylation reaction.

Synthesis of Catalytic Systems Based on Nanocomposites Containing Palladium and Hydroxycarbonates of Rare-Earth Elements

The purpose of this work is to synthesize the catalytic systems containing palladium nanoparticles and using hydroxycarbonates of yttrium and cerium as supports,and to test the catalytic activity of the obtained catalysts in the Suzuki cross-couping reaction.Nanocomposites Pd/Y(OH)CO 3 and Pd/Ce(OH)CO 3 were synthesized according to two methods:the first one-simultaneous production of nanoscale substrate and immobilization of palladium nanoparticles on its surface(nanocomposites 1),the second one-the prior synthesis of polyvinylpyrrolidone stabilized palladium nanoparticles followed by their immobilization on the nano sized substrate surface(nanocomposites 2).The reaction between phenylboronic acid and iodobenzene is chosen as a model one.The dependence of the catalytic activity of catalysts on the method of their synthesis was established.It was established that nanocomposites 2 exhibit higher catalytic activity in the selected reaction compared to the nanocomposites 1.The TOF values for the nanocomposites 1 are 6663～14617 h 1 when using the substrate Ce(OH)CO 3 and 13774～27084 h 1 when using the substrate Y(OH)CO 3,while the nanocomposites 2 reveal TOF = 87287 h 1 for the substrate Ce(OH)CO 3 and TOF = 97746 h 1 for the substrate Y(OH)CO 3 under other equal conditions.In addition,nanocomposites 2 "work" at room temperature giving a high yield of the desired product.It is noted that the support nanoparticles Y(OH)CO 3 and Ce(OH)CO 3 also exhibit catalytic activity.The yield of the final product of the reaction using them as catalysts is 55%(TOF = 11 and 8 h 1,respectively).Thus,the use of yttrium and cerium hydroxycarbonates as supports allows to decrease the palladium content in the nanocomposites to 0.01%～1% and,consequently,reduce the cost of the catalyst while maintaining its high catalytic activity.

Catalytic System for Manufacturing Butanol via Hydroformylation of Low-Carbon Olefins Developed Jointly by CNOOC and Others

Recently,the project“Development and application of low-temperature and high-selectivity catalytic system for hydroformylation of low-carbon olefins”jointly undertaken by the China National Offshore Oil Company(CNOOC)Group,the CNOOC Refining and Chemical Research Institute(Beijing),the CNOOC Tianjin Chemical Engineering and Design Institute,the Shenhua Baotou Coal Chemical Engineering Company,and the Yan’an Energy Chemical Company.

Efficient degradation of organic pollutants by S-NaTaO_(3)/biochar under visible light and the photocatalytic performance of a permonosulfate-based dual-effect catalytic system

Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency.This study used a simple hydrothermal method to prepare a non-metallic,S-doped NaTaO_(3)(S-NTO) photocatalyst,which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst.After uniform loading onto BC,the S-NTO particles transformed from cubic to spherical.The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles.The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region.In addition,a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded.The Rhodamine B,Methyl Orange,Acid Orange 7,tetracycline,and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%,99.2%,84.5%,67.1%,and 70.7%,respectively,after irradiation by a 40 W lamps for 90 min.The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC.The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments,rationally and fully utilizing solar energy,and expanding the application of photocatalytic technology to practice.

A Robust Wood-inspired Catalytic System for Highly Efficient Reduction of 4-Nitrophenol

Porous solid scaffolds play key roles in preventing nanocatalysts from agglomeration,greatly maintaining the catalytic efficiency and stability of nanocatalysts.However,facile preparation of robust scaffolds with high mass transfer efficiency for loading nanocatalysts remains a major challenge.Here,we fabricate a wood-inspired shape-memory chitosan scaffold for loading Au nanoparticles to reduce 4-nitrophenol via a simple“freeze-casting and dip-adsorption”approach.The obtained catalytic scaffold highly resembles the unidirectional microchannel structure of natural wood,resulting in robust mechanical properties and outstanding water absorption capacity.Additionally,Au nanoparticles can be firmly and uniformly anchored on the inner surface of these microchannels via electrostatic interaction,forming numerous microreactors.This catalytic system exhibits a high 4-nitrophenol conversion rate of 99%in 5 s and impressive catalytic stability even after continuously treating with more than 3 L of highly concentrated 4-nitrophenol solution(1 mmol/L).Therefore,the wood-like catalytic system presented here demonstrates the potential to be applied in the field of water treatment and environmental protection.

Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction

Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.

Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design

Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed.

Utilizing hybrid faradaic mechanism via catalytic and surface interactions for high-performance flexible energy storage system

Improving the capacitance and energy density is a significant challenge while developing practical and flexible energy storage system(ESS).Redox mediators(RMs),as redox-active electrolyte additives,can provide additional energy storing capability via electrochemical faradaic contribution on electrodes for high-performance flexible ESSs.Particularly,determining effective material combinations between electrodes and RMs is essential for maximizing surface faradaic redox reactions for energy-storage performance.In this study,an electrode-RM system comprising heterostructured hybrid(carbon fiber(CF)/MnO_(2)) faradaic electrodes and iodine RMs(I-RMs) in a redox-active electrolyte is investigated.The CF/MnO_(2)with the 1-RMs(CF/MnO_(2)-I) induces dominant catalytic faradaic interaction with the I-RMs,significantly enhancing the surface faradaic kinetics and increasing the overall energy-storage performance.The CF/MnO_(2)-I ESSs show a 12.6-fold(or higher) increased volumetric energy density of 793.81 mWh L^(-1)at a current of 10 μA relative to ESSs using CF/MnO_(2)without I-RMs(CF/MnO_(2)).Moreover,the CF/MnO_(2)-I retains 93.1% of its initial capacitance after 10,000 cycles,validating the excellent cyclability.Finally,the flexibility of the ESSs is tested at different bending angles(180° to 0°),demonstrating its feasibility for flexible and high-wear environments.Therefore,CF/MnO_(2)electrodes present a practical material combination for high-performance flexible energy-storage devices owing to the catalytic faradaic interaction with I-RMs.

Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects

The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of drugs.Nowadays,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose isomerase.Some low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and HFCS.However,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare sugars.Considering the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial products.In this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date.

Green synthesis of ZSM-5 using silica fume and catalytic co-cracking of lignin and plastics for production of monocyclic aromatics

ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium templates.The synthesized ZSM-5 were oval shaped particles with a particle size about 2.0 μm and weak acid-dominated with proper Brønsted(B)and Lewis(L)acid sites.The ZSM-5 was used for catalytic co-cracking of n-octane and guaiacol,lowdensity polyethylene(LDPE)and alkali lignin(AL)to enhance the production of benzene,toluene,ethylbenzene and xylene(BTEX).The most significant synergistic effect occurred at n-octane/guaiacol at 1:1 and LDPE/AL at 1:3,under the condition,the achieved BTEX selectivity were 24%and 33%(mass)higher than the calculated values(weighted average).The highest BTEX selectivity reached 88.5%,which was 3.7%and 54.2%higher than those from individual cracking LDPE and AL.The synthesized ZSM-5 exhibited superior catalytic performance compared to the commercial ZSM-5,indicating potential application prospect.

HZSM-5 zeolites undergoing the high-temperature process for boosting the bimolecular reaction in n-heptane catalytic cracking

High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid strength.Moreover,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke formation.Based on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.

Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust

The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co-exchange method and stepwise exchange method.It is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co-exchange method.Characterization results reveal that the Cu,Mn co-exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working environment.Moreover,a monolithic catalyst was prepared by impregnating a cordierite ceramic support into the coating slurry containing the optimized CuMn/SSZ-13 powder.The diesel engine bench tests show that Cu,Mn co-exchange gives the monolith catalyst a better catalytic property than commercial catalysts.This work provides an important guidance for the rational design of secondary-ion-assisted zeolites applied in NH_(3)-SCR.

A review of the catalytic preparation of mesophase pitch

Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperat-ures is more favorable for synthesizing mesophase pitch, because it circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. The reaction is gentle and can be easily controlled. It has the potential to significantly im-prove the yield of mesophase pitch and easily introduce naphthenic characteristics into the molecules, catalytic polycondensation is therefore a preferred method of synthesizing highly spinnable mesophase pitch. This review provides a synopsis of the selective pre-treatment of the raw materials to prepare different mesophase pitches, and explains the reaction mechanism and associated research advances for different catalytic systems in recent years. Finally, how to manufacture high-quality mesophase pitch by using a cata-lyst-promoter system is summarized and proposed, which may provide a theoretical basis for the future design of high-quality pitch molecules.

Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas detection.Specifically,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was integrated.The sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 ppb.Simulation analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for NH3.Additionally,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid interface.The sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing signal.Furthermore,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity conditions.This work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst

Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.

A critical review on direct catalytic hydrogasification of coal into CH_(4):catalysis process configurations,evaluations,and prospects

Coal catalytic hydrogasification(CCHG)is a straightforward approach for producing CH_(4),which shows advantages over the mature coal-to-CH_(4) technologies from the perspectives of CH_(4) yield,thermal efficiency,and CO_(2) emission.The core of CCHG is to make carbon in coal convert into CH_(4) efficiently with a catalyst.In the past decades,intensive research has been devoted to catalytic hydrogasification of model carbon(pitch coke,activated carbon,coal char).However,the chemical process of CCHG is still not well understood because the coal structure is more complicated,and CCHG is a combination of coal catalytic hydropyrolysis and coal char catalytic hydrogasification.This review seeks to shed light on the catalytic process of raw coal during CCHG.The configuration of suitable catalysts,operating conditions,and feedstocks for tailoring CH_(4) formation were identified,and the underlying mechanisms were elucidated.Based on these results,the CCHG process was evaluated,emphasizing pollutant emissions,energy efficiency,and reactor design.Furthermore,the opportunities and strategic approaches for CCHG under the restraint of carbon neutrality were highlighted by considering the penetration of“green”H2,biomass,and CO_(2) into CCHG.Preliminary investigations from our laboratories demonstrated that the integrated CCHG and biomass/CO_(2) hydrogenation process could perform as an emerging pathway for boosting CH_(4) production by consuming fewer fossil fuels,fulfilling the context of green manufacturing.This work not only provides systematic knowledge of CCHG but also helps to guide the efficient hydrogenation of other carbonaceous resources such as biomass,CO_(2),and coal-derived wastes.

Four-channel catalytic micro-reactor based on alumina hollow fiber membrane for efficient catalytic oxidation of CO

The traditional automotive catalytic converter using commercial ceramic honeycomb carriers has many problems such as high back pressure,low engine efficiency,and high usage of precious metals.This study proposes a four-channel catalytic micro-reactor based on alumina hollow fiber membrane,which uses phase inversion method for structural molding and regulation.Due to the advantages of its carrier,it can achieve lower ignition temperature under low noble metal loading.With Pd/CeO_(2) at a loading rate of 2.3%(mass),the result showed that the reaction ignition temperature is even less than 160℃,which is more than 90℃ lower than the data of commercial ceramic substrates under similar catalyst loading and airspeed conditions.The technology in turn significantly reduces the energy consumption of the reaction.And stability tests were conducted under constant conditions for 1000 h,which proved that this catalytic converter has high catalytic efficiency and stability,providing prospects for the design of innovative catalytic converters in the future.

Development and Catalytic Cracking Performance of Ultrastable Y Zeolite Rich in Secondary Pores

A novel ultra-stable zeolite, NSZ, rich in secondary pores was developed through the combination of gas-phase andmild hydrothermal methods. This zeolite was successfully tested in an industrial setting for the first time in the world. The porestructure characteristics of the NSZ zeolite prepared for industrial use were analyzed and characterized using BET. The resultsindicate a significant increase in the secondary pore volume of NSZ zeolite compared to the existing ultra-stable zeolite HSZ-5, which is produced through a conventional gas-phase method. The average secondary pore volume to total pore volume ratioin NSZ zeolite was found to be 58.96% higher. The catalytic cracking performance of NSZ zeolite was evaluated. The resultsshowed that the NSC-LTA catalyst, with NSZ as the active component, outperformed the HSC-LTA catalyst with HSZ-5 zeolitein terms of obtaining more high-value products (gasoline and liquefied petroleum gas) during the hydrogenated light cycle oilprocessing. Additionally, the NSC-LTA catalyst showed a significant improvement in coke selectivity.

Preparation of PrFe_(x)Co_(1-x)O_(3)/Mt catalyst and study on degradation of 2-hydroxybenzoic acid wastewater by catalytic wet peroxide oxidation

In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnation(D)method and solid-melting(G)method,respectively,with Pr(S)as the active component and Al-pillared montmorillonite as the carrier.The catalysts were applied to treat the 2-hydroxybenzoic acid(2-HA)-simulated wastewater by catalytic wet peroxide oxidation(CWPO)technique,and the chemical oxygen demand(COD)removal rate and the 2-HA degradation rate were used as indicators to evaluate the catalytic performance.The results of the experiment indicated that the solid-melting method was more conducive to preparing the catalyst when the Co/Fe molar ratio of 7:3 and the optimal structural properties of the catalysts were achieved.The influence of operating parameters,including reaction temperature,catalyst dosage,H_(2)O_(2)dosage,pH,and initial 2-HA concentration,were optimized for the degradation of 2-HA by CWPO.The results showed that 97.64%of 2-HA degradation and 75.23%of COD removal rate were achieved under more suitable experimental conditions.In addition,after the catalyst was used five times,the degradation rate of 2-HA could still reach 76.93%,which implied the high stability and reusability of the catalyst.The high catalytic activity of the catalyst was due to the doping of Co into PrFeO_(3),which could promote the generation of HO·,and the high stability could be attributed to the loading of Pr(S)onto Al-Mt,which reduced the leaching of reactive metals.The study of reaction mechanism and kinetics showed that the whole degradation process conformed to the pseudo-firstorder kinetic equation,and the Langmuir-Hinshelwood method was applied to demonstrate that catalysis was dominant in the degradation process.