As a inorganic functional material with great potential,hydrotalcite has been widely used in catalysis in recent years.This paper reviews the application of hydrotalcite materials in catalytic oxidation reactions,including three catalytic oxidation systems using hydrotalcite as catalyst or carrier,i.e.,oxidation of alcohols,phenols and alkanes using laminar transition metals as catalytically active components,epoxidation of olefins and esters using intercalated anions as catalytically active components,and oxidation of alcohols,alkanes and furfural using supported nanoparticle metal particles as catalytically active components.Perspective of application of hydrotalcite and future researches are outlined as well.

It is highly desirable to convert FCC diesel to light aromatics,which helps to solve the problem of diesel oversupply and light aromatics insufficiency in China.In this paper,the technologies for producing light aromatics from FCC diesel was reviewed,including hydrocracking mechanisms of tricyclic,bicyclic and monocyclic aromatics,and influence of properties of metal active centers (types,loadings,dispersion and proportion),properties of zeolite carriers (acidity,pore structure and chemical environment for acid sites) and balance between the two types of active centers on the catalytic behaviors.

Due to its unique pore structure,ferrierite(FER) zeolite has been widely used in heterogeneous reactions such as isomerization,carbonylation and cracking.However,its small pore size limits diffusion of macromolecules and thus shortens its service life.Moreover,different reactions have different requirements on acidity of ferrierite zeolite,which leads to limitation on its application.This paper reviews three prevalent modification strategies for FER zeolites:synthesis of nanoparticle FER zeolites,formation of intracrystalline mesoporous channels in FER zeolites and synthesis of heteroatom FER zeolites.Specific methods in these strategies can effectively overcome the shortcomings of FER zeolites,enhance their catalytic activity,increasing their catalytic active sites and prolonging their service life.It is pointed out that a single modification method is likely to bring versatile modification results,which needs to be characterized and verified through specific catalytic experiments.The future trends in modification of FER zeolites are to find cheaper and more efficient surfactants,which simplify the processes and meanwhile reduce the cost.

Wet denitrification method,being able to desulfurizing and denitrifying simultaneously,has obvious advantages in NOx emission control.Wet denitrification technologies include direct absorption,oxidation absorption,reduction absorption and complexation absorption.This article compares various wet denitrification technologies and outlines biological method,reduction method,electrolytic regeneration absorption solution method,and the types of supplementary antioxidants.

In this paper,γ-Al₂O₃ supported palladium catalysts were prepared by impregnation method and ethylene glycol reduction method.Their ozone catalytic decomposition performance was studied at 30 ℃ under WHSV of 600 000 mL·(gcat·h)^-1 and different relative humidity (RH<5% and RH>90%).The results showed that 1.5wt% Pd/γ-Al₂O₃ catalyst with 2.8 nm average particle size has superior catalytic activity.According to the characterization by XRD,XPS,TEM,SEM-EDS,O₂-TPD and H₂O-TPD,it was revealed that their excellent ozone decomposition ability was attributed to its smaller Pd particle size,higher content of Pd⁰ and oxygen mobility.In addition,the enhancement of water resistance over Pd-based catalyst was owing to the modification of H₂O adsorption capacity and adsorption strength.The relevant study provided the guideline for the development of efficient Pd-based ozone decomposition catalysts.

CePO₄ and 15%Mn/CePO₄ catalysts were synthesized by hydrothermal method using low cost cerium and manganese as the active components.The effects of synthesis method,calcination temperature,hydrothermal temperature,O₂ concentration,NO concentration and NH₃/NO ratio on the low temperature denitrification activity of 15%Mn/CePO₄ were investigated.The optimum process condition for 15%Mn/CePO₄ low temperature denitrification catalyst were obtained as follows:hydrothermal method,calcination temperature 500 ℃,hydrothermal temperature 150 ℃,O₂ concentration 3.5%;NO concentration 780 ppm;NH₃/NO ratio 0.8.

A small sand grains/TiO₂ photocatalyst was prepared by sol-gel and calcining method,aiming at avoiding agglomeration and loss of powdered photocatalyst and enhancing its recovery rate.The morphology and crystal form of the material were analyzed and tested by SEM and XRD,and its photocatalytic activity was investigated by methylene blue degradation experiment.The results showed that optimum photocatalytic effect was attained under TiO₂ mass fraction of 12%.,with methylene blue degradation of 98.77% under UV irradiation for 20 minutes.The as-prepared photocatalyst exhibited good optical stability as well.

Carbon-based photocatalyst can effectively avoid the defects of traditional TiO₂ catalysts,such as poor adsorption capacity and wide band gap.A 2D microporous carbon supported nano-TiO₂/C₃N₄ ternary composite was designed as the visible-light induced photocatalyst,and the improvement of the physical structure and photoelectric property of the composite catalyst was investigated.Photocatalytic degradation of paraxylene and rhodamine B was simulated,and the degradation efficiency reached 96.5% and 92.2% respectively,with the primary kinetic constant 7.8 times as that of commercial TiO₂ catalyst (P25).The results showed that the synergy effect for adsorption-photocatalysis of the composite catalyst was significantly enhanced,which was mainly attributed to (1) the interface effect between the graphene-like microporous carbon and the photo-active nanoparticles,which promoted the photoelectron transfer and the enrichment of pollutants during the reaction process,as well as expanding the light response range of the composite,(2) formation of binary compound semiconductor by combining nano-C₃N₄ and nano-TiO₂,which accelerated separation of photogenerated electron from the hole,and further improved photocatalytic activity of the composite catalyst.

CuO-ZnO-Al₂O₃ catalysts with different mass ratio were prepared by co-precipitation.These catalysts were carried on foamed nickel to study its effect on hydrogen production by methanol steam reforming.These catalyst were characterized by scanning electron microscopy (SEM),X-ray diffraction (XRD) and their performance was tested on a self-fabricated plate-type hydrogen preparation reactor.The results indicated that the catalysts exhibited good catalytic performance at 230-270 ℃.The methanol reforming performance increased with CuO content in a certain scope of mass proportion.Optimum result,i.e., methanol conversion of 82.4,was obtained under condition as follows:H₂O/CH₃OH molar ratio of 1.5∶1,reaction temperature 250 ℃,feed flow rate 3 mL/min,m(CuO)∶m(ZnO)∶m(Al₂O₃) molar ratio of 9∶9∶2.

A temperature programmed on-line mass spectrometry was used to screen commercially available metal oxides.Two metal oxide catalysts with low hydrogen oxidation temperature were selected for hydrogen catalytic oxidation performance investigation.The results show that the hydrogen catalytic oxidation activity of active CuO particles is significantly higher than that of other CuO catalysts due to its greater specific surface area.The hydrogen conversion over hopcalite catalyst(φ 1 mm× 3 mm) is greater than or equal to that of active CuO catalyst(dimensions of φ 2 mm × 3-5 mm) under the same preheating temperature,hydrogen concentration and GHSV.

A Pt-$SO_{4}^{2-}$/ZrO₂ solid acid catalyst was prepared by sol-gel method and adding metal Pt as a promoter and characterized.The effects of hydrolysis pH,aging time,impregnating solution concentration and calcination temperature on performance of the catalyst were investigated.The as-prepared solid acid was used to catalyze synthesis of dimethyl adipate.The results showed that the solid acid modified by Pt exhibited significantly enhanced catalytic activity and stability,with conversion of over 99% and selectivity of over 98% in synthesis of dimethyl adipate.

A solution for continuous comprehensive treatment of industrial exhaust gas containing NOx by “waste control by waste” method was proposed.Catalytic oxidation of nitric oxide (NO) followed by absorption by bauxite residue provides a feasible solution and technical supports for industrial application.Exhaust gas treated by catalytic oxidation enters an absorption loaded with bauxite residue and treated at absorption efficiency of 80%.More moisture in the exhaust can enhance service life of bauxite residue.Maximum absorption by the alkaline solution was attained under NO₂/NO concentration ratio of≥1.Cu-Mn catalysts supported on Ce-Zr solid solution were designed and used for NO catalytic oxidation to NO₂.NO conversion of 50% was attained under Cu/Mn molar ratio of 1/9,loading of 3% and 200 ℃.

Calcium sulfate whiskers are fibrous single crystals of calcium sulfate synthesized from gypsum or industrial by-products by a specific process and formula.It is a kind of inorganic material with many excellent characteristics,such as complete shape,stable size and uniform cross-section.However,due to the influence of preparation methods and equipment,the yield of calcium sulfate whiskers is not high and the quality is poor,which limits the application of calcium sulfate whiskers to a certain extent.The preparation methods of calcium sulfate whiskers at home and abroad and their advantages and disadvantages were introduced.The methods of calcium sulfate whisker crystal shape control and calcium sulfate whisker modification and its mechanism,the application of calcium sulfate whisker in modification and environmental protection were reviewed.Finally,some constructive ideas for the related research were provided.

Platinum-based catalyst is one of the key materials of proton exchange membrane fuel cell (PEMFC),and the catalytic materials should have high activity,high conductivity,high stability,corrosion resistance and other properties.At present,platinum-based catalysts have some problems such as poor durability,low utilization rate and high price.These problems have seriously restricted the commercialization of PEMFC.The preparation of catalysts with high stability,high activity and low cost has become the research focus of scholars at present.In this paper,two directions for improving the catalytic activity of platinum-based catalysts are summarized.One is to modify the carbon carrier to improve the electrocatalytic performance,and the other is to load single metals,bi-metals and metal compounds to improve the electrocatalytic performance.According to the above two aspects,this paper expounds the research and application of platinum-based catalysts to improve catalytic activity in the catalytic process.It is proposed that the catalytic activity of the catalyst can be improved from two aspects at the same time,by changing the catalyst components and carrier characteristics to achieve better catalytic effect,while improving the catalytic activity,reducing the platinum content,and forming an economical and stable fuel cell catalyst.

Heavy metal pollution is still a global environmental problem,which poses a serious threat to human life.Various methods have been explored to eliminate heavy metal pollutants in the environment.However,most methods are limited by high cost,processing time,geological problems,etc.Metal immobilization and microbial methods have been proved to be feasible in the treatment of heavy metal pollutants in soil.This paper summarizes the general situation of soil heavy metal pollution,and expounds the shortcomings and advantages of various remediation methods.Remediation of contaminated soil needs to consider remediation methods,soil pollution degree,site conditions,wide adoption and various possibilities at different remediation stages.

Methods for preparing porous alumina were primarily introduced,including the solid-phase method,the liquid-phase method and the gas-phase method.Physical and chemical properties of alumina prepared by different methods were compared,such as particle size,specific surface area,dispersity.Alumina shows good application prospects in the fields of infrastructure,adsorption,catalysis,optics and medicine due to excellent physical-chemical property.

Due to higher corrosion temperature and 100% concentration,the corrosion rate of molten KOH was 100 to 1000 times that of KOH solution.Fe-based catalyst substrate steel tube for Fischer-Tropsch synthesis prepared with the optimal parameters of corrosion at 500 ℃ for 3 h with carbon 20 material and 20 g KOH·(5 tubes)^-1,showed the highest corrosion rate of 10.28%.A small amount of KOH remained on the surface of tube,many irregular rough micro-pits and a large number of pores appeared.Carbon 20 material was more easily corroded than 316L and 304 due to its carbon content.Higher dosage of KOH and higher corrosion temperature led to higher corrosion rate.Serious passivation film formed after corrosion of 5 h reduced the corrosion rate.

V-Mo/Ti and V-W/Ti De-NOx catalysts were prepared and treated at 650 ℃ subsequently.XRD,N₂ adsorption-desorption,H₂-TPR,UV-vis,NH₃-TPD,and O₂-TPD analyses were carried out to investigated the change in the physiochemical properties of the different catalysts.De-NOx performances of catalysts before and after heat treatment were studied.It was found that the thermal treatment at 650 ℃ did not change the crystal structure of the vanadium-titanium based catalysts,but could lead to the decrease of their BET surface area and pore volume.Besides,the thermal treatment resulted in the decline of reducibility,acidity,and chemical adsorbed oxygen of the catalysts,which led to the decrease of the catalytic performance of the catalysts.V-Mo/Ti catalyst was more affected by thermal treatment than V-W/Ti catalyst.As a result,V-W/Ti-T catalyst exhibited better catalytic performance than that of the V-Mo/Ti-T catalyst.In other words,V-W/Ti catalyst possessed stronger thermal stability than that of the V-Mo/Ti catalyst.

Metal-organic framework compound Cu-BTC was synthesized by ultrasonic-assisted hydrothermal method and characterized by XRD,SEM,BET,FT-IR and EDS.The characterization results showed that Cu-BTC was a microporous material with octahedral structure and high crystallinity.The desulfurization performance of the synthesized catalyst was evaluated by adsorption removal of sulfide-dibenzothiophene in simulated oil (n-octane-dibenzothiophene).The desulfurization efficiency of regenerated adsorption material using solvent elution remained 85.46% after being repeatedly used for three times,indicating that the metal-organic framework compound Cu-BTC synthesized by ultrasonic assisted hydrothermal synthesis has a good application prospect in adsorption desulfurization.

α-Al₂O₃ support (Al₂O₃-B) was prepared by ball-milling method using γ-AlOOH as raw material.Compared with the α-Al₂O₃ prepared by calcination,the surface area of Al₂O₃-B was larger,reaching 70.7 m²·g^-1.Pd/α-Al₂O₃ catalyst (Pd/Al₂O₃-B) was synthesized by impregnation.The catalyst was characterized by X-ray diffraction (XRD),N₂ adsorption-desorption,NH₃-temperature-programmed desorption (TPD) and transmission electron microscopy (TEM) and tested in the CO oxidative coupling to dimethyl oxalate reaction.Pd/Al₂O₃-B showed wonderful catalytic activity in the CO oxidative coupling reaction,space-time yield of dimethyl oxalate reaching 2 175 g·(L·h)^-1.

Aiming at the spray drying process of catalytic cracking catalyst,a 100 kg·h^-1 single spray gun pressure spray drying tower model was established to simulate the distribution of hot air in the drying tower under different tower structures,and the influence of hot air outlet position on temperature distribution,velocity distribution and air flow trajectory in the drying tower was investigated.The results show that when there is no hot air distribution plate in the drying tower,the hot air is in a swirling downward state,there is an obvious low temperature zone downstream of the spray gun,and the uniformity of flow field distribution is relatively poor;When two layers of hot air distribution plates with uniform holes are set,the hot air moves vertically downward,the temperature is gradient distribution,and the flow field distribution is uniform;When two layers of hot air distribution plates with central holes are set,the hot air flow is in a centralized distribution state,and the distribution of air velocity and temperature near the spray gun tends to be high in the middle and low around.Changing the position of the hot air outlet in the outlet flue has a significant effect on the flow field distribution in the drying tower.

In this paper,the thermal efficiency model of the electric heating furnace is established,and the effects of the air volume,operating pressure and sealing structure on the thermal efficiency are analyzed.The furnace heat loss is reduced by coating nano-materials on the outer surface of the furnace hearth.The operation results showed that the deviation between the simulation results and the operation results is within 2.5%.The thermal efficiency of the furnace is increased from 81.7% to 85.7% by optimizing the operation parameters and equipment structure,and 210 500 CNY annual operation cost is saved.It has created good economic benefits for enterprises.

With graphene oxide as the structure directing agent,resorcinol-formaldehyde-melamine as the precursor,and melamine as the nitrogen source,three-dimensional stacked graphene based nitrogen doped hierarchical porous carbon nanosheets (NCNS) with uniform thickness and adjustable nitrogen content were prepared by sol-gel and carbonization.After loaded with Pd,Pd/NCNS catalyst was applied in PTA hydrofining.Compared with commercial Pd/C catalyst,Pd/NCNS catalyst shows higher activity,which can be attributed to its shorter diffusion channel,nitrogen doping and its high Pd dispersion.

Hydroisomerization of alkanes is an important reaction in the production of high-quality blended fuels,white oil and lube base oil.The modification methods,mechanism and effects of 10-membered ring molecular sieves,including ZSM-22,ZSM-23 and ZSM-48,which are commonly used in hydroisomerization reaction,are reviewed.We discuss the effects of alkali treatment,alkali metal/rare earth elements modification and transition metal-substitution on zeolites.The existing problems of the researches and future development directions are pointed out.

The main granulation processes for the preparation of millimeter-sized spherical alumina carriers using pseudo boehmite as the aluminum source are reviewed,including oil-ammonia column method,oil drop granulation method,water column method and rotation method,etc.The differences of each granulation process and the performance differences of the prepared spherical alumina are specifically introduced,and the focus and development direction of future research on the preparation of γ-Al₂O₃ spherical carriers are prospected.

The catalysts for vapor-phase oxidation of durene to pyromellitic dianhydride were introduced.The research focused on the study in reaction mechanism,catalyst composition and optimizing of forming method.The reaction performances were greatly improved by optimizing the proportion of vanadium and titanium and the utilization of element doping.The new molding process optimizes the coating structure and strength of the catalyst.In the future,the addition of various additives should be combined with the optimization of catalyst preparation and forming process to improve the catalytic performance.It was proposed that the development of the catalysts with high-load operation,high yield of pyromellitic dianhydride and long life time was the future research direction.

A series of Fe(OH)_x-decorated Pt/BN catalysts were tested for hydrogenation of crotonaldehyde.Compared to the low selectivity to crotyl alcohol on bare Pt/BN (less than 5%),the Fe(OH)_x modification resulted in significant improvement in selectivity.The best performance was obtained on a catalyst with an Fe/Pt molar ratio of 0.1 (0.1FePt/BN),which gave a crotyl alcohol formation rate of 166.6 μmol·g_Pt^-1·s^-1 at 80 ℃ in liquid phase with a selectivity of 72.7%,and a turnover frequency (TOF) of 0.042 78 s^-1 at 70 ℃ in gas phase with a selectivity of 80.5%.Various characterization results revealed that the Pt-Fe(OH)_x interaction altered electronic properties of the Pt species at the interfacial sites,which consequently facilitated the activation of adsorbed carbonyl group and thus the selectivity to unsaturated alcohol.Moreover,quantitative analysis of the kinetic data indicated that the TOF of the interfacial Pt site was 0.377 53 s^-1 at 70 ℃,which was three order of magnitude higher than that on the non-interfacial Pt site (0.56×10^-3 s^-1).

To achieve the goal of emission peak and carbon neutrality,in addition to increasing energy savings and emission reduction,it is necessary to further strengthen the utilization of greenhouse gases such as CO₂ and CH₄.Dry reforming of methane (DRM) to produce H₂ and CO syngas from CO₂ and CH₄ is a hot topic of interest.γ-Al₂O₃ supports with morphologies of nano-rod,nanosheet,and nano particle were prepared by a “two-solvent” method,and the effect of support morphologies on Ni/γ-Al₂O₃ catalyzed DRM was investigated.The results showed that the Ni/γ-Al₂O₃ activity was influenced by the morphology of the γ-Al₂O₃ support,and Ni supported on nano-rod Al₂O₃ exhibited excellent activity with initial conversions of 84.3% and 75.4% for CO₂ and CH₄,respectively,and R_H2/CO of 0.88 in syngas,with the highest stability during the reaction and no signs of deactivation.Compared with Ni supported on commercial Al₂O₃ catalysts,CO₂ and CH₄ conversions were increased by 23.6 and 26.8 percentage points,respectively.This is due to the high specific surface area of Ni supported on nano-rod Al₂O₃ catalysts,which facilitates the dispersion of Ni metal on the surface and the presence of more active sites of Ni to inhibit the agglomeration of Ni particles during the reaction;Ni supported on nano-rod Al₂O₃ exhibits the highest number of basic sites,which facilitates the activation of CO₂ adsorption on the catalyst surface.

The Rb-Sr-Fe-TiO₂ photocatalyst was successfully prepared by sol-gel method and characterized by scanning electron microscopy,X-ray diffraction and Fourier transform infrared spectroscopy.Under visible light induction,methylene blue (MB) was used to evaluate its photocatalytic performance.Results showed that the optimal doping ratio of RbCl,Sr(NO₃)₂ and FeCl₃ was found to be m_RbCl: $m_{Sr(NO_{3})_{2}} : m_{FeCl_{3}}: m_{TiO_{2}}$ =2:1:0.2:100,and the optimal catalyst concentration was 1.0 g·L^-1.Degradation efficiency of 4 mg·L^-1 methylene blue solution reached 98.56% within 3 h over Rb-Sr-Fe-TiO₂ photocatalyst.Rb-Sr-Fe-TiO₂ overcomes the defects of traditional TiO₂ in poor adsorption capacity and poor visible light responsiveness,improves the photocatalytic activity of the material,and is expected to be widely used in wastewater treatment.

The one-pot synthesis of copper,cesium-containing catalysts supported on ordered mesoporous alumina via self-assembly of Cu-Ce precursor [Cu(NO₃)₂·2.5H₂O and Ce(NO₃)₂·6H₂O] and aluminum isopropoxide in the presence of triblock copolymer (as a structure directing agent) was investigated in this paper.The sorption and decontamination of VS over synthesised copper,cesium-containing catalysts and ordered mesoporous alumina was studied.The results show that the degradation efficiency of VS was the highest over Al-0.05Cu-0.05Ce bimetal catalyst,which was 98.01% after 4 days of reaction.There are relatively more oxidation products on Al-0.05Cu-0.05Ce,the reaction mainly occurs in the rupture of S—C bonds and P—S bonds,and the broken fragments would be combined or oxidated further.This may be due to the fact that the cerium element in CeO₂ can undergo a reversible transformation between Ce³⁺ and Ce⁴⁺ under the influence of the environment,and can catalyze the oxidation reaction of VS.

The effect of compound catalyst on catalytic hydrogenation performance of FCC refinery was studied.HY molecular sieve and γ-Al₂O₃ were prepared with NaY molecular sieve and pseudo boehmite as raw materials respectively,and meanwhile P modified γ-Al₂O₃ was prepared by impregnation method.The catalysts were characterized by XRD,BET,Py-IR and SEM.A type autoclave was used to carry out the catalytic experiment of FCC recycle oil hydrogenation.The effects of the support and the ratio of active component Ni-Mo on the catalytic reaction are investigated.The results show that phosphorus modification is beneficial to improve the texture characteristics of γ-Al₂O₃ and the amount of B acid.After the HY and P@γ-Al₂O₃ are compounded,the acidity and pore distribution of the carrier are further optimized.The obtained test data show that when m(P@γ-Al₂O₃)∶m(HY)=8∶2,and the active component distribution ratio is n(Ni)∶n(Mo)=1∶2,the hydrogenation performance of catalyst is the best,and the obtained product has the most saturated content and the highest hydrogen-carbon ratio.

Pseudo boehmite (PB) used in hydrogenation catalyst for petroleum refining process requires large pore volume,specific surface area and particular pore structure.Aluminum sulfate method and carbonization method are usually used in industry.In order to improve the pore volume and pore diameter,super-pore PB was prepared by reaming method.At the same time,conventional macroporous PB was prepared by aluminum sulfate method and carbonization method.Three kinds of PBs were prepared into alumina,support and catalyst,characterized and analyzed the pore structure,and evaluated the hydrogenation performance of the catalyst.Low temperature N₂ adsorption-desorption test shows that the pore volume and pore diameter of support prepared by reaming method are the largest,and the pore diameter distribution of support prepared by aluminum sulfate method is the most concentrated.Mercury injection analysis shows that the PBs prepared by the three methods are mainly composed of intercrystalline pores and intergranular pores.After being extruded into the carrier,all the large pores between the particles disappear,and only intergranular pores exist.XRD analysis shows that the PB prepared by reaming method has the largest crystal size,which is one of the reasons for its large pore volume and pore diameter.SEM and TEM analysis show that the PB prepared by aluminum sulfate method presents fibrous structure,the PB prepared by carbonization method presents smaller sheet structure,and the PB prepared by reaming method presents larger sheet structure,which is also the fundamental reason for the different pore structures of the three PBs.The fixed bed evaluation results show that for the heavy oil hydrotreating reaction,the activities of PBs prepared by aluminum sulfate method,carbonization method and reaming method increase in turn after prepared to catalyst,which is due to the help of large pore size to improve the diffusion rate of heavy oil macromolecules.

Triethylamine is a kind of nitrogenous volatile organic compounds and its catalytic combustion treatment is of great significance to relevant enterprises and industries.In this paper,ZSM-5 and transition metals Co,Cu and Fe modified ZSM-5 were used as catalysts to study the influence of surface acidity and specific surface area on catalytic performance.The lowest temperature required for complete conversion of triethylamine on the catalyst is in the order of Co-ZSM-5(220 ℃)<Cu-ZSM-5(280 ℃)<ZSM-5(300 ℃)<Fe-ZSM-5(320 ℃).Co-ZSM-5 has 98% selectivity for CO₂ and 90% selectivity for N₂ at (220-240) ℃,resulting in less exhaust gas.

In this study,the cellular denitrification catalyst which had been running for 4 000 h in a cement plant was taken as the test object,and its geometric appearance,physical and chemical characteristics and catalytic performance were studied and analyzed.The results showed that the pore of the catalyst sample was blocked,the compressive strength was good but the wear rate was high.The content of the main active ingredient was decreased,and alkaline earth metal and heavy metal poisoning was existed,which would led to the reduction of the active sites on the catalyst surface and the deactivation of the catalyst.The process performance test results showed that the current denitration efficiency and ammonia escape index were lower than the design threshold.Timely replacement or regeneration management is recommended to ensure the safe and stable operation of the unit.

2-cyclopentenone synthesized from self-condensation of biomass derivative cyclopentenone can be used as a precursor of high density fuel.In this paper,the catalysts for the synthesis of 2-cyclopentenone from self-condensation of cyclopentenone are reviewed.According to the phase state of the reaction system,it can be divided into homogeneous catalyst and heterogeneous catalyst.Although homogeneous catalyst has excellent catalytic activity,it has some disadvantages,such as corrosion equipment,environmental pollution and non-recycling.Among heterogeneous catalyst,solid base catalyst (CaO and MgO) has the best catalytic performance,but the catalyst has the problem of deactivation.Secondly,acid-base bifunctional catalyst (MgAl-HT) has good catalytic performance due to acid-base active centers.However,compared with the catalytic activity of homogeneous catalyst,its catalytic performance needs to be further improved.Therefore,it is necessary to develop green and efficient solid acid-base bifunctional catalysts to meet the development requirements of green chemistry,and to lays a foundation for the preparation of biofuels.

Shape-selective molecular sieves such as ZSM-5 are widely used in industry due to their unique structure and pore effect,as well as high hydrothermal stability,adjustable silica-alumina ratio,strong acidity,and low synthesis cost,etc.ZSM-11 belongs to the same Pentasil molecular sieve family as ZSM-5,and their structures are similar,but the pore channel of ZSM-11 molecular sieve is a cross-shaped cross pore channel,which means ZSM-11 molecular sieve has superior mass transfer diffusion ability and coke reduction advantage compared to commercial ZSM-5 molecular sieve.This paper focuses on the synthesis and application of ZSM-11 molecular sieve,classifies it by synthesis purpose and mode,and elaborates on ZSM-11 molecular sieve in catalytic cracking,alkylation of benzene,denitrification,aromatization,methanol to olefin and other new applications.In order to accelerate its wider application in the industrial field,it is proposed that ZSM-11 molecular sieve can only be developed in the direction of solvent-free,template-free and in situ synthesis by solving its synthesis cost and environmental problems.

Vanadium-based catalyst is a representative commercial NH₃-SCR catalyst and it is widely used for exhaust gas treatment of thermal power plants,factories and ships.The main disadvantage of vanadium-based catalyst is the high working temperature window.To further improve the performance of the catalyst,various methods and technologies are on goingly studied.This paper summaries the main reports of vanadium-based catalysts in very recent 10 years.The works are classified and illustrated as the modification of active components such as the Ce,Fe,Cu and other metal oxides and non-metallic oxides,the role of carrier type and structure,the influence of DPF and other supports,anti alkali metal poisoning,SO₂ resistance,and Hg⁰ removal,as well as the reaction kinetics,which could be a reference for the related researchers.

In order to broaden the light response range of TiO₂,Cu,Ag-doped TiO₂ photocatalys were prepared by a hydrothermal method and its morphology and composition were characterized by FT-IR (Fourier transform infrared spectroscopy),XRD(X-ray diffraction),SEM (scanning electron microscope),UV-vis DRS (UV-Vis diffuse reflectance absorption spectroscopy) and other analytical methods.Photocatalytic performance of the as-synthesized catalyst was tested in Pinacol Coupling Reaction by using methane acid and isopropanol.The results show that the catalysts are anatase spherical nanoparticles.Doping metal makes the range of light absorption wider and improves the photocatalytic ability.Cu and Ag double doped photocatalysts show higher catalytic activity for Pinacol Coupling Reaction.

A novel ZnSnO₃/cellulose composite was prepared by a simple hydrothermal synthesis method using natural cellulose as the template.The effect of the concentration of precursors on the preparation of the composite was investigated.The composite materials were characterized by SEM,XRD and TG,and its photocatalytic properties were investigated by photocatalytic degradation of Rhodamine B(RhB).The results demonstrated that the composite material perfectly maintained the unique hierarchical porous network structure of the filter paper,and ZnSnO₃ particles were successfully coated on the surface of cellulose fibers through hydrothermal treatment.As the photocatalyst for degradation of RhB,the ZnSnO₃/cellulose composite had better photocatalytic performances compared with pure ZnSnO₃,and it degradation efficiency could reach more than 98%.In addition,the degradation for RhB of the ZnSnO₃/cellulose was still 94.3% after 5 cycles,demonstrating that the composite had excellent cycling stability.The as-prepared composite material with macro fibrous structure can provide a strategy for solving the problem of recovery of catalytic materials in practical applications,which has a great significance on the further development of photocatalysis and reuse of energy.

Using sequential extraction methods H₂O-H₂SO₄ and H₂O-NaOH,the contents and distribution of loaded metals (Cu,Cr and Ag) in each extract and residue of ASC impregnated carbon were investigated and analyzed,as well as the content and distribution of metal ions, {\mathrm{NH}}_4^{+},CN^- and Cl^- ions in the aqueous extraction solution and residues of the carbon samples against poison gas (HCN or CNCl).The results showed that the metal oxides loaded on the carbon were CuO,CrO₃,Cr₂O₃ and Ag₂O,of which CrO₃ would be in the form of (NH₄)₂CrO₄.These metal oxides undergo changes in species by the chemical reaction of CrO₃ reduction to Cr₂O₃ and the conversion of CuO into a water-soluble Cu²⁺ (such as CuCl₂) during the protection against HCN or CNCl.In addition, {\mathrm{NH}}_4^{+} ions or amino compounds that can be dissociated into {\mathrm{NH}}_4^{+} ions were also found on the surface of the contaminated impregnated carbon samples.