最新刊期
卷 50 ， 期 6 ， 2025
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摘要：Zeolite is a significant crystalline porous material. Due to its tunable chemical compositions, strong acidity, large specific surface area, strong thermal and hydrothermal stability, it has been widely utilized in various fields, such as chemical engineering, energy and so on. Because of unique porosity characteristics, small-pore DDR zeolite has shown great potential in gas separation and catalysis processes. Research progresses in the synthesis of DDR zeolite and its applications in gas separation and catalysis have been reviewed. The methods for synthesizing DDR zeolite powder and membrane were introduced, focusing on the strategies that have been developed to regulate the physicochemical properties and thus to improve the performance. The application progress in DDR zeolite in gas adsorption separation and membrane separation and catalytic reactions, such as methanol to olefins, was summarized. Gas separation efficiency and catalysis structure-activity relationship were emphasized. Finally, the current status and challenges faced in the research and development of DDR zeolite were pointed out, and the key directions for future research were envisioned, in order to provide ideas for the rational design of zeolite and promote the industrial application of DDR zeolite.关键词：DDR zeolite;zeolite membrane;synthesis regulation;gas separation;catalysis;methanol to olefin2|0|0更新时间：2025-06-23 -
摘要：CO2 hydrogenation to methanol is one of promising route for CO2 utilization. Cu/ZnO catalysts have garnered considerable attention due to their unique catalytic properties. A series of Pd doping Cu/ZnO catalysts were prepared by co-precipitation, impregnation, and mechanical mixing methods. The catalysts were characterized by ICP-OES, N2 physical adsorption/desorption, XRD and so on. The catalytic performances of each catalyst were tested under the conditions of temperature from 170 ℃ to 250 ℃, pressure of 5.0 MPa and gas space velocity of 4000 mL/(g·h), and the effects of different Pd doping methods on the structures, morphologies and performances of Cu/ZnO catalysts were studied. The results show that Pd-Cu/ZnO-C catalyst prepared by co-precipitation method exhibits higher CO2 conversion rate, methanol selectivity and methanol space-time yield compared to the undoped Cu/ZnO catalyst. The co-precipitation method facilitates the uniform distribution and high dispersion of Pd in the catalyst. The synergistic catalysis between noble metal Pd and Cu effectively enhances hydrogen dissociation and spillover capabilities. Furthermore, the Pd-Cu/ZnO-C catalyst has small particle sizes, large specific surface areas and excellent reduction abilities, leading to a reduction of apparent activation energy. At low temperatures of 170 ℃ and 190 ℃, CO2 conversion rates of Pd-Cu/ZnO-C catalysts are 5.5% and 8.9%, respectively, with methanol selectivities of 82.2% and 74.9% and methanol space-time yields of 0.058 g/(g·h) and 0.088 g/(g·h), respectively.关键词：CO2 hydrogenation;Pd doping;Cu/ZnO catalyst;low temperature methanol synthesis197|0|0更新时间：2025-06-23 -
摘要：The catalytic dry reforming of CO2 and CH4 holds significant importance. On one hand, it enables the recycling of two major greenhouse gases. On the other hand, its reaction products, H2 and CO, serve as critical feedstocks for Fischer-Tropsch synthesis. Nickel-based catalysts have attracted widespread attention due to their high catalytic activity and low cost. La2NiO4/MCM-41 serials bimetallic catalysts were prepared using the sol-gel method, with MCM-41 as the support. The effects of calcination temperature, Ni content (mass fraction, the same below), n(La)/n(Ni), and reaction temperature on its CH4-CO2 catalytic reforming performance were investigated. The catalysts before/after reaction were characterized using BET, SEM-EDX, XRD, H2-TPR, TG-DSC, Raman, and TPO techniques. The results show that spinel La2NiO4 is the primary form of nickel in the catalyst and exhibites good dispersion. As the Ni content increases, the specific surface area and pore volume of the catalysts decrease rapidly. Ni content and reaction temperature are found to have the most significant impact on the catalytic performance of bimetallic catalysts. Under reaction conditions of 700 ℃, 0.10 MPa and 18000 mL/(h·g), the conversion rates of CH4 and CO2 after 100 h reaction show varying degrees of decline compared to the initial values. However, their equilibrium conversion rates still reach 72.89% and 81.08%, respectively. Post-reaction characterization reveals significant carbon deposition on the catalyst surface, primarily in the form of carbon nanotubes. The size of these carbon nanotubes increases as the reaction time prolongs, eventually covering the active Ni sites on the catalyst surface and leading to catalyst deactivation.关键词：Ni-La bimetallic catalyst;La2NiO4/MCM-41;CO2-CH4;dry reforming195|0|0更新时间：2025-06-23 -
摘要：Oxidative cracking process of light alkanes (C2~C6 alkanes) is one of the key pathways for producing light olefins. Oxidative cracking can be divided into two types: Catalytic oxidative cracking (COC) and redox oxidative cracking (ROC). In COC systems, the presence of oxygen often leads to over-oxidation, resulting in higher CH4 and COx yields and lower olefin yields. Although ROC systems decreases the issue of over-oxidation, their high operating temperatures and process complexity limit broader industrial application. The reaction mechanism of COC process was summarized, and catalysts used in this system were summarized, including rare-earth metals, noble metals, alkali metals and other catalysts. Meanwhile, the ROC reaction mechanism was discussed, along with the vanadium-based and perovskite catalysts. Based on analysis of current research, the challenges faced by oxidative cracking catalysts were summarized, and the future development direction was proposed, aiming to provide reference for the development of new and highly efficient oxidative cracking catalysts.关键词：light alkanes;oxidative cracking;catalysts;light olefins;reaction mechanism226|0|0更新时间：2025-06-23 -
摘要：As the demand for degradable plastic polyglycolic acid (PGA) has been increasing in China, thus the demand for methyl glycolate (MG) as a raw material for the synthesis of PGA has also rapidly increased. A series of Cu/PAC-x catalysts were prepared by impregnation method for the hydrogenation of dimethyl oxalate (DMO) to MG by pretreatment of pitch-based activated carbon (PAC), and the catalytic performances of Cu/PAC-x catalysts were investigated. The Cu/PAC-x catalysts were characterized by N2 adsorption/desorption, FT-IR, XRD, TEM, H2-TPR, XPS and CO-TPD, and the effects of different pre-treatment methods of the PAC on the catalytic performances of catalysts were investigated. The results show that mixed acid treatment can improve the Cu+/Cu0 ion pairs activation performances of catalysts, thereby improving the catalyst activity. At 210 ℃, 1.9 MPa, n(H2):n(DMO) of 170 and space velocity of 0.26 g/(g·h), the catalytic activity of Cu/PAC-SN catalyst is the highest, and the DMO conversion rate, MG selectivity and yield rate of Cu/PAC-SN catalyst reach 85.4%, 72.8% and 62.2%, respectively.关键词：methyl glycolate;dimethyl oxalate;pre-treatment;Cu/PAC catalysts172|0|0更新时间：2025-06-23 -
摘要：Growth of energy demand and depletion of fossil fuels have made efficient conversion of heavy crude oil a research focus. Alkane cracking technology can convert long-chain alkanes into short-chain hydrocarbon products, thereby increasing the economic value of long-chain alkanes. HY zeolites are one of the commonly used catalysts for alkane catalytic cracking due to their advantages of high specific surface area and suitable acid strength. However, there are relatively few theoretical studies on the effect of HY zeolites acid strengths on alkane cracking mechanism. Using periodic density functional theory calculation method, with propane and n-hexane as model substrates, the effects of HY zeolites with different acid strengths (Al substitution structures are 1Al substitution, 3Al substitution and 6Al substitution, and the corresponding n(Si)/n(Al) are 47, 15 and 7, respectively) on the alkane cracking mechanism were systematically studied, and the difficulty of breaking different C—C bonds in n-hexane was analyzed. The results show that with the increase of the Brønsted acid strength of HY zeolites, the apparent Gibbs free energy barrier of the protonation reaction of propane and n-hexane decreases, and the catalytic activity of HY zeolites in alkane cracking reaction is enhanced. The difficulty of breaking the three C—C bonds in n-hexane from easy to difficult are C3—C4 bond, C2—C3 bond and C1—C2 bond.关键词：HY zeolites;Brønsted acid strengths;n-hexane;cracking mechanism;periodic density functional theory55|0|0更新时间：2025-06-23 -
摘要：The efficiency of direct combustion of low rank coal is low and pollution is serious, which causes great waste of coal resources. Realizing efficient and clean utilization of low rank coal is of great significance to alleviate energy shortage in China. Microwave pyrolysis technology has the advantages of low energy consumption, high pyrolysis efficiency and safety and environmental protection, which provides a new idea for low rank coal pyrolysis. Firstly, the principle of microwave pyrolysis technology and its application in coal (mainly low rank coal) pyrolysis were summarized. Then the factors affecting coal microwave pyrolysis were analyzed, including coal properties, microwave absorbers, pyrolysis atmospheres and co-pyrolysis. Finally, the problems and future research directions of low rank coal microwave pyrolysis technology were analyzed and prospected.关键词：low rank coal;microwave pyrolysis;microwave absorbers;pyrolysis atmospheres;co-pyrolysis50|0|0更新时间：2025-06-23 -
摘要：In order to explore the co-pyrolysis transformation characteristics and collaborative reaction mechanism of different waste tires and biomass, and realize the directional high-value utilization of pyrolysis oil components, the pyrolysis behaviors were investigated by thermogravimetric analysis and fixed-bed pyrolysis tests. The composition and transformation path of pyrolysis production were compared and analyzed in different kinds of waste tires and rice husks or straw mixture. Thermogravimetry experiment result shows that co-pyrolysis can effectively decrease the temperature required for the pyrolysis reaction, which can reduce the pyrolysis energy consumption. The synergistic effect is more significant when small tires participate in co-pyrolysis than that of Truck and Bus Radial. The results of fixed bed experiment shows that co-pyrolysis can effectively improve the conversion of aromatic hydrocarbons to aliphatic hydrocarbons and the conversion of oxygen-containing substances to hydrocarbon substances. However, co-pyrolysis will lead to the production of carbon dioxide, which will decrease the calorific value of pyrolysis gas. In addition, the mass fraction of C in co-pyrolysis carbon is significantly decreased, and the S also has a tendency to transform from gas-solid phase to liquid phase. It is also found that large amounts of neutral metal oxides in Passenger Car Radia and rice husk ash can promote the hydroxylation of benzene rings, while large amounts of alkaline metal oxides in Truck and Bus Radial and straw ash can promote the gasification reaction.关键词：waste tires;biomass;co-pyrolysis;synergistic effect;metal oxides109|0|0更新时间：2025-06-23 -
摘要：The low-carbon transformation of the oil refining industry is crucial to achieving “carbon peaking and carbon neutrality” goal. A “fuel-based” refinery was taken as the research object, and the emission factor method and the material balance method were adopted to calculate its carbon emission in the base year, and the distribution characteristics of carbon emission sources were analyzed based on the accounting results. Furthermore, using the scenario analysis method, carbon emission trends under medium control (MC-CE) and deep control (DC-CE) scenarios were predicted, and the carbon reduction potential of eight mitigation measures under different scenarios was evaluated. The results show that the refinery’s total carbon emission in the base year is 71.7683 × 104 t/a, with an average carbon emission factor (carbon emissions per unit of crude oil processed) of 0.2691 t/t. Fuel combustion and catalytic coking are identified as the primary sources of carbon emissions. Under the MC-CE scenario, carbon emissions in 2030 and 2040 are projected to decrease by 18.84% and 28.80%, respectively, compared to the base year. Under the DC-CE scenario, carbon emissions in 2030 and 2040 are expected to decline by 37.08% and 53.59%, respectively, compared to the base year. Based on the research findings, it is recommended that refineries accelerate energy-saving retrofits, actively introduce low-carbon technologies and vigorously promote the application of clean energy to facilitate the low-carbon transition.关键词：refinery;carbon emissions;emission reduction potential;low-carbon transition44|0|0更新时间：2025-06-23 -
摘要：Under the “carbon peaking and carbon neutrality” background, the economic feasibility of biomass-based green methanol production was evaluated. Three biomass gasification-based green methanol production schemes were considered (Scheme 2 couples green hydrogen with Scheme 1, and Scheme 3 further utilizes the CO2 generated in the front-end processes of Scheme 2). Assuming a biomass daily processing capacity of 2000 t, green electricity price of 0.20 CNY/(kW·h), green hydrogen price of 1.1 CNY/m3 and green methanol sales price of 4500 CNY/t, the impact of biomass price on the annual net profit, investment payback period, unit operation cost and production cost of green methanol production was investigated. The results show that when the biomass price is 300 CNY/t, Scheme 1 achieves an annual net profit of 5.53 × 108 CNY, income tax payments of 1.84 × 108 CNY and an investment payback period of 4.4 years. Scheme 2 achieves an annual net profit of 7.80 × 108 CNY, income tax payments of 2.60 × 108 CNY and a payback period of 4.7 years. Scheme 3 achieves an annual net profit of 9.37 × 108 CNY, income tax payments of 3.12 × 108 CNY and a payback period of 5.2 years. Scheme 1 has the lowest unit operation cost for green methanol (1387 CNY/t), and the unit production cost is 1925 CNY/t. Scheme 3 produces the highest amount of green methanol (67 × 104 t/a), and under the same biomass price conditions, it results in higher annual net profit and income tax payments than Schemes 1 and 2. The break-even green methanol sales prices for Scheme 1, Scheme 2 and Scheme 3 are 1925 CNY/t, 2433 CNY/t and 2635 CNY/t, respectively. Scheme 1 results in the highest CO2 emissions (56.3 × 104 t), whereas the process in Scheme 3 can achieve near-zero carbon emissions. When the carbon tax price is 79.42 CNY/t, Scheme 3 saves carbon tax expenses of 4470 × 104 CNY/a and 1950 × 104 CNY/a compared to Scheme 1 and Scheme 2, respectively.关键词：biomass gasification;green methanol synthesis;coupling;green hydrogen;carbon emission reduction93|0|0更新时间：2025-06-23 -
摘要：Nitrogen oxides (NOx) and nitrous oxide (N2O) emissions from diesel vehicles pose significant threat to human health and the ecological environment. NH3-selective catalytic reduction (NH3-SCR) technology is one of the most effective methods for controlling NOx emissions from diesel vehicle exhaust, while the direct catalytic decomposition of N2O (abbreviated as “N2O decomposition”) is considered the most promising technology for reducing N2O emissions. The core of both technologies lies on the development and application of catalysts. Fe-based zeolite catalysts exhibit excellent catalytic performance in NH3-SCR and N2O decomposition reactions, providing a promising pathway for the simultaneous and efficient removal of NOx and N2O. The catalytic mechanisms of Fe-based zeolite catalysts in NH3-SCR and N2O decomposition reactions were summarized, and the effects of preparation methods, topological structures, doped metal additives and coexisting gases on their physicochemical properties, NH3-SCR activity and N2O decomposition performance were discussed. Specifically, the formation and distribution of Fe species in Fe-based zeolite catalysts are significantly influenced by the preparation methods and zeolite topological structures. The introduction of metal additives not only increases the number of acid sites in the catalyst but also improves the dispersion of Fe species, thereby optimizing catalytic performance. Furthermore, coexisting gases such as NO, O2, and H2O have varying degrees of impact on the N2O decomposition activity of Fe-based zeolite catalysts. Finally,an outlook on future research directions for Fe-based zeolite catalysts was provided, and recommendations for catalyst design optimization and performance enhancement were offered.关键词：Fe-based zeolite catalysts;NH3-SCR;N2O direct catalytic decomposition;catalytic mechanisms25|0|0更新时间：2025-06-23 -
摘要：Catalytic oxidation technology is an effective strategy for the treatment of volatile organic compounds (VOCs), in which the design and optimization of novel catalysts play a key role in achieving efficient VOCs conversion. CeO2 supports were prepared by calcination and precipitation methods, respectively. Subsequently, Pt was loaded on the CeO2 surface via sodium borohydride reduction to prepare Pt/CeO2 catalysts. The effects of different preparation methods on the catalytic performance of Pt/CeO2 for toluene oxidation were investigated. The catalysts were characterized by XRD, N2 adsorption/desorption, UV Raman spectroscopy, XPS and O2-TPD. The evolution behavior of toluene during the reaction process was studied by in situ DRIFTS. The results show that different preparation methods regulate the concentration of active oxygen species in the Pt/CeO2 catalysts. Among them, the Pt/CeO2-P catalyst prepared by the precipitation-reduction method exhibits a higher concentration of active oxygen species and oxygen vacancies, which promote the activation and conversion of toluene, leading to the formation of easily degradable formate species that are ultimately oxidized to CO2 and H2O. Under the conditions of toluene volume fraction of 0.1% and a space velocity of 48000 mL/(g·h), the Pt/CeO2-P catalyst achieves T50 and T90 (reaction temperature at which the toluene conversion rate reaches 50% and 90%) at 157 ℃ and 168 ℃, respectively.关键词：Pt/CeO2;catalytic oxidation;oxygen vacancies;toluene2|0|0更新时间：2025-06-23 -
摘要：The extensive use of fossil energy leads to the increasing CO2 content in the atmosphere, and the efficient and environmentally friendly CO2 capture technology has become a research hotspot. To explore the effect of structural characteristics of deep eutectic solvents on their CO2 absorption properties, glycerol was used as hydrogen bond donor, octylethylenediamine (Octen) or 2-ethylhexylethylenediamine (EtHexen) as hydrogen bond acceptor to prepare straight chain type deep eutectic solvent Glycerol-Octen and branched chain type deep eutectic solvent Glycerol-EtHexen. The functional groups, hydrogen bonds, melting points and viscosities of Glycerol-Octen and Glycerol-EtHexen were characterized, and their CO2 absorption properties were analyzed by density functional theory calculation and molecular dynamics simulation. The results show that there are strong O—H···N type hydrogen bond effects between hydrogen bond donors and hydrogen bond acceptors of Glycerol-Octen and Glycerol-EtHexen. Glycerol-Octen and Glycerol-EtHexen have the best CO2 absorption when combined with three and four CO2, respectively, with corresponding hydrogen bond energies of 39 kJ/mol and 47 kJ/mol, respectively. The viscosities of Glycerol-Octen and Glycerol-EtHexen are relative low at room temperature, with values of 409.0 mPa·s and 231.4 mPa·s, respectively. Under the same conditions, Glycerol-EtHexen exhibits better CO2 absorption property than Glycerol-Octen, with CO2 absorption rates of 70.5% and 63.5%, respectively. At 25 ℃ and 0.1 MPa, absorbed CO2 mainly distributes at the gas-liquid interface of Glycerol-Octen and Glycerol-EtHexen. This study can provide a new idea for the development of efficient and environmentally friendly CO2 absorbers.关键词：deep eutectic solvents;density functional theory;CO2 absorption;molecular dynamics76|0|0更新时间：2025-06-23 -
摘要：The heat and mass transfer performances of organic amine absorbents can be improved by adding nanoparticles, then the CO2 absorpiton performances of organic amine absorbents can be improved and the energy consumptions of desorption can be reduced. However, the addition of nanoparticles may cause particle agglomeration, which will adversely affect the CO2 absorption performances of the organic amine absorbents. The mixed amine base solution of 2.5 mol/L 2-((2-aminoethyl) amino) ethanol (AEEA) and 0.5 mol/L N-methyldiethanolamine (MDEA) was prepared. Effects of the types, particle sizes and mass concentrations of nanoparticles (MoO3, WO3, ZnO or MgO) and surfactants on the CO2 absorption and desorption performances of nanofluids were studied by the CO2 bubble absorber and simulated power plant flue gas (N2 and CO2 volume fractions were 85% and 15%, respectively). The results show that for MoO3 nanofluids with MoO3 particle size of 10 nm and mass concentration of 0.9 g/L, under hexadecyltrimethylammonium bromide mass concentration of 0.6 g/L, its absorption enhancement factor and desorption enhancement factor are 1.1400 and 1.2045, respectively, and the comprehensive enhancement factor reaches the maximum value (1.1723).关键词：CO2;mixed amine;nanofluids;absorption;desorption206|0|0更新时间：2025-06-23 -
摘要：Hydrogen production in water electrolysis is a mild and efficient process, where catalysts play an irreplaceable role in the hydrogen evolution reaction (HER). In scaling up hydrogen production, developing efficient, stable and inexpensive catalysts presents a significant challenge for hydrogen production in water electrolysis. The research progress of commonly used HER catalysts, including precious metals, non-precious metals and carbon-based catalysts was reviewed. The electrocatalytic activity and stability of the above HER catalysts were analyzed in detail. The general improvement strategies, such as heteroatom doping, structural engineering and crystal and defect engineering were summarized to enhance the electrocatalytic activity and stability of catalysts.关键词：water electrolysis;hydrogen evolution reaction;catalyst;electro-catalysis1312|0|0更新时间：2025-06-23 -
摘要：The development of hydrogen energy is an effective method for achieving the “dual carbon” goals and ensuring national energy security. Methane cracking to produce hydrogen is an important process for converting methane into hydrogen, and has broad application prospects. Liquid metal catalysts have been employed in methane cracking to produce hydrogen, facilitating carbon emission reduction and addressing the challenges of high energy consumption, low production yield and catalyst deactivation in traditional methane cracking technologies. The mechanisms of methane cracking to produce hydrogen were summarized. The current research progress on liquid metal catalysts was analyzed. The feasibility and superiority of single-atom liquid metal catalysts for methane cracking to produce hydrogen were studied. The fluidity of liquid metals can mitigate catalyst deactivation caused by coking. At the same time, liquid metals have relatively low melting points, which can to some extent reduce the temperature of methane cracking systems. The development and utilization of liquid metal single-atom catalysts for methane cracking to produce hydrogen can significantly improve methane conversion rates and obtain more hydrogen and high added value carbon products through reactions.关键词：methane;hydrogen production;liquid metal;single-atom catalyst350|0|0更新时间：2025-06-23
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