Propylene oxide (PO) is an important organic chemical raw material,which is mainly used to produce polyether polyols,propylene glycol, various non-ionic surfactants,and so on.The research prog-ress on catalytic selective epoxidation of propylene to propylene oxide in recent years were reviewed in this paper,including the catalytic processes with oxygen,H₂O₂,in situ generation of H₂O₂ and organic peroxides as oxidant.Green catalytic process for preparing propylene oxide in the future were expected.It is necessary to focus on the propylene epoxidation process of biomimetic catalysis,in situ H₂O₂,design of high selectivity catalyst and the catalytic reaction mechanism.

This paper summarize the photocatalytic degradation of methyl orange (MO) processes,including catalysts,reactors,influence factors,and measures to improve the efficiency of photocatalytic reactions.The efficiency of MO degradation by different catalyst systems is highlighted in the review,and advances in photocatalytic reactors are also presented.The electron-hole separation-transfer efficiency of the catalyst surface and the alignment of the reactor light source with the solution transmission rate are crucial for enhancing the photocatalytic degradation of MO.Therefore,the authors divided the currently available methods for enhancing MO photocatalytic degradation into three categories:(1)Enhancing the light absorption capacity of the composite catalyst;(2)Homogenizing the light source in the reactor;(3)Increasing the loading mechanism of the catalyst to increase the contact-specific surface area and micro-flow characteristics.The idea of increasing the efficiency of photocatalytic is presented in this paper.It is necessary to start with the discrepancy between the source distribution and the transmittance of the solution,and then optimize the source arrangement in the reactor based on the uniform light distribution.

As the crude oil reserves decreased dramatically,it’s urgent to upgrade heavy feedstocks into light oils to relieve the supply pressure of crude oil.The slurry-phase hydrogenation is an advanced technology to efficiently upgrade heavy feedstocks.The challenge of slurry-phase hydrogenation lies in developing high active hydrogenation catalysts.In this work,MoS₂/C catalysts were synthesized by a facile one-step hydrothermal method with glucose and maltose as the soluble carbon sources.The compositions and structures of MoS₂/C catalysts were characterized by X-ray diffraction,Raman spectroscopy,elemental analysis,scanning electron microscopy and high-resolution transmission electron microscopy.The characterization results indicated that the MoS₂/C catalysts are composed of nanosheets with MoS₂-C-MoS₂ carbon intercalated structure.The nanosheets display enlarged interlayer distance,short slabs and few stacking layers.The catalytic hydrogenation activities of MoS₂/C catalysts were evaluated with phenanthrene as the model compound of heavy oils in the slurry-bed reactor.MoS₂/C catalyst with glucose as carbon precursor and the C to Mo atomic ratio of 5 in the raw materials exhibits the highest catalytic hydrogenation activity.For MoS₂/C-G-5 catalyst,the phenanthrene conversion,hydrogenation percent of phenanthrene and the selectivity to the deep hydrogenation product octahydrophenanthrene can respectively reach 85.6%,37.4% and 56.4%,which are 1.6,2.4 and 2.3 times as high as those of MoS₂ catalyst synthesized without carbon source.The MoS₂-C-MoS₂ carbon intercalated nanostructures of MoS₂/C catalyst could expose more hydrogenation active sites to improve its hydrogenation activity significantly.

The preparation of nickel sulfide electrocatalysts with abundant active sites and excellent intrinsic activity by simple methods toward efficient hydrogen production is crucial for sustainable hydrogen energy economy.In this study,we used a simple two-step electrochemical deposition method to construct a novel nitrogen doped nickel sulfide electrocatalyst (named Ni-S-N/Ni/NF) with multi-level pore structure on nickel foam used as substrate.The Ni-S-N/Ni/NF catalyst not only has a large number of active sites,but also exhibits enhanced intrinsic activity and excellent hydrogen evolution performance in 1 M KOH electrolyte,achieves current density of 10 mA·cm^-2 under overvoltage of only 84 mV.This work is expected to provide valuable reference for the preparation of high-performance nickel sulfide catalysts.

Due to the complex composition and harsh treatment conditions of waste gas produced by the propylene industry,conventional catalytic combustion catalysts are unable to meet operational requirements.As a result,the market is largely dominated by foreign catalysts.Kaili Catalyst & New Materials Co.,Ltd. has developed its own line of relevant catalysts (Cat-O),compared with the mainstream impo-rted catalysts,Cat-H,Cat-M,and Cat-C,and evaluated their performance and aging detection under simulated conditions of acrylic acid and acrylonitrile waste gases.Results show that the imported catalyst,Cat-M,exhibits superior activity and stability.Although the catalyst Cat-O has slightly milder activity,its water resistance and stability are far superior to those of the imported Cat-H and Cat-C catalysts.Furthermore,evaluation of the waste gas in side stream indicates that the Cat-O catalyst has great potential for industrialization.

HMS mesoporous molecular sieves were synthesized successfully using tetraethyl orthosilicate (TEOS) and primary amines as raw materials and template,respectively.After loading with active components,Pt-Sn/HMS catalysts were prepared and applied to propane dehydrogenation to propylene.The effects of the carbon chain length of primary amine surfactant and the ratio of water to ethanol on the pore structure of HMS mesoporous molecular sieves were investigated.The results of XRD and N₂ adsorption-desorption showed that the pore diameter,wall thickness,surface area and pore volume of mesoporous molecular sieves increased with the increase of template chain length.The appropriate ratio of water to ethanol is beneficial to obtain mesoporous molecular sieves with larger surface area and pore volume,and more ordered mesoporous structure.The results of the catalytic reaction and thermal analysis show that,the pore characteristics of HMS mesoporous molecular sieves could directly affect the catalytic performance of the Pt-Sn/HMS catalysts.Only when the HMS sample with large surface area and pore volume was used as support,the Pt-Sn/HMS catalyst could show excellent catalytic performance in the reaction of propane dehydrogenation.The Pt-Sn/HMS-0.60-16 catalyst shows the optimal catalytic performance in propane dehydrogenation to propylene,with an average propane conversion of 46.5%,an average propylene selectivity of 94.1%,and a carbon deposition of only 3.4% (mass fraction) after 24 h reaction.

The catalysts of CuO-CoO and CuO-Fe₂O₃ were prepared by co-precipitation method.The reduction kinetic parameters of pure CuO,Co₃O₄ and Fe₂O₃ as well as CuO-CoO and CuO-Fe₂O₃ catalysts were determined using temperature programmed reduction (TPR) technique.The results demonstrated that the reduction of Co₃O₄ and Fe₂O₃ was improved by the addition of CuO,the reduction temperature of both catalysts were moved to the lower temperature and the reduction activity energy were significantly reduced.The reduction mechanism of iron oxide was changed by the addition of Cu.

It is of great significance to study the effect of molding conditions on the performance of shaped catalysts in practical industrial applications.Taking Co/Beta forming catalyst as the research object,the influence of different binder mass ratio,peptizer concentration and extrusion aid content on the performance of forming catalyst was analyzed.The activity of shaped catalysts in catalytic decomposition of N₂O was studied in a gas-solid phase catalytic reaction evaluation device.The catalysts were characterized by intensity measurement,X-ray diffraction (XRD),BET specific surface area measurement,hydrogen temp-erature-programmed reduction (H₂-TPR),and ammonia temperature-programmed desorption (NH₃-TPD).The experimental results show that the best forming condition were mass fraction of SB powder 30%,concentration of nitric acid 6% and mass fraction of safflower powder 4%.Under the determined optimum forming conditions,the radial compressive crushing force of catalyst was 110.3 N·cm^-1,T₉₉ of N₂O conversion was 460 ℃。

The calcined catalyst contains a certain amount of sodium oxide,which reduces the stability of the catalyst.Filtering and washing can reduce the content of sodium oxide in the catalyst and improve the activity of the catalyst.Using HRSY-5 molecular sieve and microsphere catalyst as samples,the effects of calcination temperature,pH value of exchange solution,exchange time,ammonium chloride concentration in exchange solution,and washing water on Na₂O content were investigated to provide experimental reference for reducing the sodium chloride content of the catalyst.The results show that the content of Na₂O in catalyst could reduce to 0.09% (mass fraction) after treatment of molecular sieve and catalyst.

The HY zeolite was obtained from NaY zeolite via ion exchange and high temperature calcinations and used as catalyst for alkylation between benzene and benzyl chloride in a batch-wise reactor.Effects of calcination temperature of HY zeolite,dosage of catalyst,reaction temperature,reaction time and proportion of raw materials were investigated.The optimum condition were obtained as follows,calcination temperature was 800 ℃,reaction temperature was 140 ℃,catalyst dosage was 10% mass fraction of benzyl chloride,reaction time was 1 h,n(benzene)∶n(benzyl chloride)=10∶1.Under the optimum condition,benzyl chloride conversion was 98.32%,and diphenylmethane selectivity was 80.46%.The HY zeolite catalyst exhibited higher catalytic activity and selectivity.

Wastewater containing phenol and cyanide formed in the process of coal coking would cause certain harm to water ecology.It is of positive economic and environmental value to study the efficient treatment technology of wastewater containing thiocyanate.In this study,coke powder was used as the source of carbon,and magnetic Fe₃O₄/C materials were prepared by equal volume impregnation and heat-limited carbon reduction,and then characterized by XRD and N₂ adsorption-desorption techniques.The XRD results indicate that the average grain size of Fe₃O₄ loaded is 10.8 nm,and the specific surface area of Fe₃O₄/C material is 6.8 m²·g^-1.20%Fe₃O₄/C material was used to treat simulated industrial coking thiocyanate wastewater (the concentration was 2.5 g·L^-1).The removal efficiency can reach 99.84% when the concentration of copper salt is 0.03 mol ·L^-1,dosage of catalyst was 1.25 g,initial pH of waste water was 5.6,and the reaction temperature is 45 ℃ for 2 h.The Fe₃O₄/C catalyst had good stabi-lity.Kinetic simulation showed that the reaction followed a quasi-second-order kinetic model,and the main adsorption process was controlled by chemical action.In this experiment,coke powder was used as a carrier to prepare Fe₃O₄/C material.Through the synergistic effect of iron and copper species,the chemical precipitation method was used to achieve the efficient removal of thiocyanate from simulated wastewater,providing theoretical support for industrial coking wastewater treatment.