最新刊期
卷 50 ， 期 2 ， 2025
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摘要：Carbon emissions from the excessive consumption of fossil fuels have led to a significant increase in atmospheric CO2 concentrations, causing a series of severe environmental issues. Capturing and converting CO2 into high-value chemicals is one of the key pathways for carbon reduction. Thermal catalytic CO2 hydrogenation to olefins has attracted considerable attention due to its excellent CO2 conversion efficiency and product yield. The modified Fischer-Tropsch route and the methanol intermediate route are the mainstream processes currently, with the former primarily based on Fe-based catalysts and the latter on metal oxide/molecular sieve composite catalysts. First, the recent research progress on catalysts for thermal catalytic CO2 hydrogenation to olefins was summarized, including the reaction mechanisms of different routes, the strategies for regulating the physicochemical properties of catalysts and the key factors affecting olefin synthesis performance. Furthermore, the application prospects of CO2 hydrogenation to olefins processes were discussed to provide a reference for research in the field.关键词：CO2 hydrogenation;thermal catalysis;olefins;Fe-based catalysts;bifunctional catalysts130|0|0更新时间：2025-02-27 -
摘要：The traditional thermal catalytic conversion of methane requires harsh reaction conditions, while high-energy electrons in plasma can collide with methane molecules to generate radicals at low temperatures, leading to the formation of C2 hydrocarbons and hydrogen through recombination reactions. Dielectric barrier discharge (DBD) plasma-assisted non-oxidative coupling of methane has become a potential technology for high-value utilization of methane due to its simple reactor structure and uniform electric field distribution. The research progress on DBD plasma-assisted non-oxidative coupling of methane technology was reviewed, the activation mechanism and reaction pathway of methane in plasma systems were elucidated, and the key factors affecting methane conversion rate and product selectivity were analyzed from the perspectives of reactor structure, process parameters and catalysts. It points out that the activation mechanism of methane, the synergistic effect between plasma and catalysts, as well as the optimization of reactor structure and process flow, are important research directions for the future. This can provide a reference for the research on methane conversion technology.关键词：plasma;methane conversion;dielectric barrier discharge53|0|0更新时间：2025-02-27 -
摘要：Doping metal ions can regulate the coordination environment and construct structural defect sites of active metals in the composite metal oxides, and then improve the catalytic performances of composite metal oxides as catalysts. Ni-based composite oxide catalysts by doping Zn, Ce or Fe were prepared by sol-gel method and used in catalyzing partial oxidation of methane (POM) reaction. The crystal structures, structure properties, reduction performances and species chemical states of catalysts were characterized by XRD, N2 physical adsorption/desorption, H2-TPR and XPS and so on. The results show that doping metal ions effectively regulates the distribution of Ni and reactive oxygen species. Among them, doping Ce in Ni0.76Ce0.24Cr2 catalyst enhances the interaction force between Ni and other metals, increases the number of reactive oxygen species on the catalyst surface. The H2 selectivity achieves nearly 100% at the high temperature stage (550 ℃ to 600 ℃).关键词：composite metal oxide;partial oxidation of methane;species distribution;metal ion doping;product selectivity69|0|0更新时间：2025-02-27 -
摘要：The reverse water gas shift (RWGS) reaction can not only achieve CO2 conversion, but also be a key step in the process to produce CO, and it is of great significance to develop efficient RWGS catalysts. MoO3 can catalyze RWGS reaction, but it has the problems of low CO2 conversion rate, high activation temperature, etc. Cu has good CO2 catalytic hydrogenation activity, and is often used as the active phase of CO2 hydrogenation catalysts, which has a great application prospect in the field of RWGS. Cu/MoCe, Cu/MoTi and Cu/MoGa catalysts were prepared by co-precipitation, and the physicochemical properties and configuration-activity relationships of the catalysts were explored through characterization and activity testing. The results show that Cu/MoCe catalyst has the highest activity with the CO yield of 47.9% at the reaction temperature of 500 ℃, n(H2):n(CO2) of 4:1 and the space velocity of 30000 mL/(g·h). The smaller grain size of the solid solution phase CuMoO4 in Cu/MoCe catalyst, the formation of Ce-O-Mo asymmetric oxygen vacancies in the supports, the redox cycle between Ce3+/Ce4+ ion pairs and the synergistic effect between oxygen vacancies and active phases jointly promote the RWGS reaction, which make Cu/MoCe catalyst exhibits great catalytic activity and provides a new idea for the design of RWGS catalysts.关键词：reverse water gas shift reaction;Cu-based catalysts;oxygen vacancies;CO2 conversion79|0|0更新时间：2025-02-27 -
摘要：As the key step in the two-step synthesis of methyl methacrylate (MMA) from ethylene, ethylene carbonylation to produce methyl propionate usually uses a homogeneous catalytic system composed of precious metals, phosphine ligands and acidic additives. Sulfonic acid, as the generally used acidic additive, is beneficial for improving catalyst activity and stability, but also has process problems such as equipment corrosion and sulfonic acid accumulation. By optimizing the catalytic system, the appropriate amount of sulfonic acid required to maintain the performance of ethylene carbonylation reaction was determined, and a second additive to replace sulfonic acid was further introduced. An impact evaluation was conducted on the core elements of process development, including reaction atmosphere and solution compositions, trace impurities and reactor volumes. The potential application of this catalytic system in ethylene and high carbon alcohol carbonylation was also explored. The results show that under the conditions of reaction temperature of 100 ℃ and operating pressure of 1.2 MPa, when the amount of sulfonic acid added (mass fraction, the same below) is 0.0145%, the turnover frequency (TOF) reaches 44400 h-1. The TOF significantly decreases to 34868 h-1, when the amount of sulfonic acid added in the reaction solution decreases to 0.0070%. Maintaining the amount of sulfonic acid added at approximately 0.0070% and introducing a second additive with an addition amount of 0.0304% to 0.0596% does not contribute to the recovery of ethylene carbonylation reaction performance. When no sulfonic acid added and the amount of the second additive added is 0.0595%, the TOF decreases to 11941 h-1, but when the amount of the second additive added increases to 2.0125%, the TOF increases to 38758 h-1. After the reaction, there is no obvious precipitation in the solution, and the catalyst stability is good (TOF is the average value of reaction for 3 h ). Within a certain range, the higher the CO volume fraction and methanol content, the faster the rate of ethylene carbonylation reaction. Adding 0.1% (mass fraction) ethanol to the reaction solution and 0.442% (volume fraction) H2 to the reaction gas does not significantly affect the ethylene carbonylation reaction rate, thus reducing the purification requirements for the methanol, ethylene and CO in raw materials. After enlarging the reactor volume from 250 mL to 1000 mL, the reaction indicators such as TOF and turnover number (TON) are basically consistent, with a TON about 130000 and a selectivity of over 99% for methyl propionate after reaction for 3 h. This study can provide reference for the development of ethylene carbonylation reaction processes.关键词：carbonylation;ethylene;catalyst;homogeneous reaction99|0|0更新时间：2025-02-27 -
摘要：Due to the complex conjugated structure of the two unsaturated chemical bonds in cinnamaldehyde (CAL) molecules, the selective hydrogenation of C==C and C==O bonds in CAL to produce desired products is a challenging task. Pd single atoms, Pd nanoparticles and a combination of Pd single atoms and Pd nanoparticles supported on nanodiamonds (ND) were prepared (Pd1/ND（w(Pd) = 0.05%）,PdNPs/ND（w(Pd) = 0.25%）and Pd1+NPs/ND（w(Pd) = 0.25%）, respectively). The influences of the geometric and electronic structures of Pd on catalytic performances of catalysts in CAL hydrogenation were studied. The ND was characterized by HR-TEM, XRD and XPS. The results show that ND is a kind of high-crystallinity and high-surface-energy support with abundant oxygen functional groups and single-atom anchoring sites. The geometric and electronic structures of Pd1+NPs/ND were analyzed by HADDF-STEM, AC-TEM and XPS. The results show that compared to Pd/C, Pd1+NPs/ND has higher n(Pdδ+)/n(Pd0), further confirming the coexistence of Pd single atoms and Pd nanoparticles. The catalytic performances of Pd1+NPs/ND, Pd/C, Pd1/ND and PdNPs/ND for CAL hydrogenation were investigated under the conditions of the temperature of 40 ℃, the H2 pressure of 1 MPa and n(Pd)/n(CAL) of 0.023%. The results show that Pd1+NPs/ND exhibites much higher catalytic activity and hydrocinnamaldehyde (HCAL) selectivity than Pd/C. Pd1/ND and PdNPs/ND show low catalytic activities. Therefore, there is a synergistic effect between Pd single atoms and Pd nanoparticles in the efficient catalytic CAL hydrogenation by Pd1+NPs/ND.关键词：Pd single atoms;Pd nanoparticles;nanodiamond;cinnamaldehyde hydrogenation;synergetic catalysis41|0|0更新时间：2025-02-27 -
摘要：Salicylic acid compounds are an important raw material widely used in fine chemicals such as medicine, spices, dyes, pesticides and rubber additives, etc. However, based on the Kolbe-Schmitt reaction, the preparation of salicylic acid compounds with CO2 as a carboxyl source has some problems, such as high temperature, high pressure, long reaction time and low yield. A new method for the synthesis of salicylic acid compounds by CO2 carboxylation phenol and 4-substituted phenol was presented, which uses KOH as deprotonation base, xylene as solvent, Cs2CO3, K2CO3 and 2,4,6-trimethylphenol potassium salt (TMPK) as cocatalysts to achieve CO2 efficient carboxylation phenol and 4-substituted phenol. The physicochemical properties of each carboxylation product were characterized. The effects of catalyst dosage, CO2 pressure, temperature, cocatalyst dosage, reaction time and reaction substrate on the carboxylation reaction of phenol and 4-substituted phenol were systematically investigated. The possible reaction mechanism of the synthesis of salicylic acid and 5-substituted salicylic acid cocatalyzed by carbonate and TMPK was proposed. The results show that the catalyst combination of Cs2CO3 + TMPK effectively optimizes the reaction conditions. Under mild conditions, the preparation of salicylic acid compounds by efficient CO2 carboxylation phenol (one-way yield of 60%) and 4-substituted phenol (one-way yield of 60%~90%) was realized. The ortho-selectivity of carboxylation products synthesized by this method is as high as 100%.关键词：Kolbe-Schmitt reaction;CO2;Cs2CO3;2,4,6-trimethylphenol;5-substituted salicylic acid;carboxylation73|0|0更新时间：2025-02-27 -
摘要：With the rapid development of polyester industry in China, the demand for ethylene glycol（EG） continues to increase, and the use of additives to modify copper-based catalysts has become one of the effective strategies to improve the yield of ethylene glycol. Zr additive-doped Cu/SiO2 nanotube catalysts were prepared by one-pot method for dimethyl oxalate hydrogenation to ethylene glycol. The catalysts were characterized by XRD, N2 adsorption/desorption, FT-IR, TEM, H2-TPR and XPS. The effects of Zr contents (n(Zr)/n(Cu)) on catalytic performances was investigated. The results show that introduction of appropriate amount of Zr (n(Zr)/n(Cu) = 0.05) is conducive to the copper species uniform distribution on the nanotubes, which improves the dispersion of copper species. In addition, the electron transfer between Cu and Zr enhances the interaction between metals, which is conducive to the stability of Cu+ species on catalyst surface, thereby improving the activity and stability of catalyst. Under the conditions of reaction temperature of 210 ℃, reaction pressure of 2.4 MPa, n(H2)/n(DMO) of 100, weight hourly space velocity of 0.405 h-1 and reaction time of 40 h, Cu-Zr0.05/SiO2 shows the best catalytic performance. The DMO conversion and EG selectivity of Cu-Zr0.05/SiO2 reach 99.1% and 91.9%, respectively.关键词：ethylene glycol;dimethyl oxalate hydrogenation;zirconia additive;Cu/SiO2 nanotube90|0|0更新时间：2025-02-27 -
摘要：Biomass is green renewable energy with abundant reserves and is expected to replace fossil energy to reduce carbon emissions. However, its high oxygen content, high moisture content and high dispersion lead to a series of problems such as poor grinding performance and difficult storage and transportation, making it difficult to use as resources. The research progress on torrefaction pre-conditioning technology (hereinafter referred to as “torrefaction”) to optimize the quality of biomass and its pyrolysis products at home and abroad was reviewed. It is emphasized that torrefaction can improve physicochemical properties of biomass and optimize the quality of pyrolysis products. The emission reduction and energy conservation effects of torrefaction were summarized. Torrefaction can improve the grinding energy, calorific value and activation energy of biomass, and help the energy characteristics of torrefied biomass to reach the level of fuel coal. The specific surface area of biochar after torrefaction combined pyrolysis increases, the pore structure becomes more complex, the contents of oxygen and acidic substance decrease, and the content of combustible components in pyrolysis gas increases, so the quality of products is improved. Suggestions were made for the development of this technology, and its potential applications were discussed. It is proposed that the torrefaction combined with pyrolysis technology can replace coal as one of the important thermal conversion technologies for preparing clean oil, carbon materials and syngas, and torrefaction biomass combined with thermal conversion and utilization of coal can improve the clean utilization level of coal, so as to realize the low-carbon reengineering of future industrial processes, and provide technical supports for China to achieve “carbon peaking and carbon neutrality” goals, revitalize rural areas and ensure energy security.关键词：biomass;torrefaction;pyrolysis;physicochemical properties;product quality;emission reduction and energy conservation79|0|0更新时间：2025-02-27 -
摘要：Slurry bed residue hydrocracking technology is an important means for refinery transformation and development, and a major approach for the green and efficient utilization of residue oil. The core of the technology is to ensure the efficient conversion of asphaltenes and other polycyclic aromatic hydrocarbons, while inhibiting coke formation through condensation, which can be enhanced by optimizing reaction conditions, developing high-performance catalysts, and improving the equipment and processes. In recent years, slurry bed residue hydrocracking technology has developed rapidly and has been applied in industrial production. The research progress was summarized from the perspectives of reaction condition optimization, high-performance catalyst development, and equipment and process optimization. Through the optimization of blending components, reaction temperature and space velocity, catalysts, equipment and processes, relevant studies have achieved varying degrees of improvement in the yield of high-value components, the techno-economic performance, and the operating cycle of the equipment.关键词：residue;asphaltene;slurry bed hydrocracking;high-efficient conversion;catalyst82|0|0更新时间：2025-02-27 -
摘要：The fundamental goal of developing clean and efficient coal conversion technologies is to improve the utilization efficiency of the effective elements C, H and O in coal. Coal is rich in C element, which will inevitably produce CO2 during the utilization process. Therefore, in the process of coal utilization, the generated CO2 is coupled through chemical reactions to be reused into organic chemicals (such as alcohols, ethers, acids and esters, etc.), which has important academic significance and significant social benefits in coal chemical technology and in the field of organic synthesis chemistry. Starting from the carbon emission characteristics of the coal processing and utilization industry, three coal low-carbon conversion technologies, namely coal coupled with renewable energy, carbon capture, utilization and storage and CO2 chemical utilization were introduced, respectively. By chemical reactions to convert CO2 generated during the process of coal processing and utilization into oxygen-containing chemicals can not only reduce the direct emission of CO2 while ensuring that the original process is not changed, but also produce high value-added chemicals needed by the human society, turning “waste” into treasure. For this purpose, the latest chemical process research progress on simulating CO2 to prepare oxygen-containing organic compounds such as methanol, formic acid, dimethyl ether and dimethyl carbonate by Aspen Plus was emphasized. The technical characteristics of the process and the performance parameters, such as material conversion, energy utilization, economic benefits and so on were summarized. Based on advanced low-carbon coal conversion technologies, a new process of coal-based CO2 low-carbon conversion was proposed, which is dedicated to promoting the development of clean coal conversion technology coupled with CO2 chemical reuse to industrial applications.关键词：efficient coal conversion;low-carbon technology;CO2 chemical utilization;oxygen-containing organic compounds124|0|0更新时间：2025-02-27 -
摘要：CO preferential oxidation (CO-PROX) reaction is a key step in H2 purification of fuel cells, which is of great significance to improve the efficiency of fuel cells and reduce harmful emissions. Monolithic catalysts with good thermal stability and anti-aggregation, low pressure drop, high mechanical strength and good mass and heat transfer characteristics have gradually become the focus of research. Research progress on monolithic catalysts (metal monolithic catalysts, ceramic monolithic catalysts and 3D printed polymer monolithic catalysts) in CO-PROX reaction was reviewed, with the focus on analyzing the effects of monolithic frames and catalyst coating preparation techniques on their catalytic performances. And the advantages and disadvantages of different types of CO-PROX reaction monolithic catalysts were compared. The current challenges faced by CO-PROX reaction monolithic catalysts were analyzed and their future research directions were prospected.关键词：CO preferential oxidation reaction;monolithic catalysts;fuel cells;monolithic frames;catalyst coatings158|0|0更新时间：2025-02-27 -
摘要：Direct air carbon capture (DAC) technology is a negative carbon emission technology with good application prospect, and chemical absorption DAC technology is one of the research hotspots in the field. The development of carbon dioxide absorbent, improvement of carbon dioxide absorption tower and optimization of carbon dioxide absorption process for chemical absorption DAC technology were reviewed. The reaction processes and mechanisms of strong alkali solutions, amine solutions, amino acid salt solutions and ionic liquids as carbon dioxide absorbents were introduced. The operation performances and improvements of carbon dioxide absorption towers, such as laminar flow tower, open-cell foam exchanger, plate air contactor and biomass carbon interfacial reactor were described. The effects of waste heat utilization and energy introduction on chemical absorption DAC system were analyzed. The analysis results of technical economy and carbon efficiency of chemical absorption DAC system were summarized, and the future developments of chemical absorption DAC technology were prospected.关键词：direct air carbon capture;chemical absorption;process optimization;technical economy analysis;carbon efficiency100|0|0更新时间：2025-02-27 -
摘要：Carbon capture, utilization and storage (CCUS) technology is essential for achieving CO2 emission reduction. However, the high energy consumption of the capture processes is a significant barrier to the widespread adoption of CCUS technology. To address this issue, the low efficiency of waste heat recovery in the Rankine cycle of Ca and Cu looping CO2 capture technology, a novel Ca and Cu-combined looping post-combustion CO2 capture technology is proposed. Using cement plant flue gas as the capture source, a process simulation model was constructed using Aspen Plus software. Thermodynamic performance and economic cost analysis were conducted for the typical Ca looping cement plant integrated system (system I), the conventional Ca and Cu looping cement plant integrated system (system II), and the novel Ca and Cu-combined looping cement plant integrated system (system III). Additionally, the impact of various operational parameters on the thermal performance of system III was investigated. The results indicate that under carbon capture rate of 90% and according to unit mass CO2, the primary energy consumption for CO2 reduction in system III is -0.87 MJ/kg and the reduction cost is 265.8 CNY/t. Compared to system I and system II, the primary energy consumption for CO2 reduction in system Ⅲ decreases by 2.91 MJ/kg and 2.00 MJ/kg, respectively, while the reduction cost decreases by 42.67% and 41.41%, respectively. Under certain conditions, reducing the CO2 capture rate, increasing the calciner temperature or increasing the air reactor temperature can reduce the energy consumption of system III. When the air reactor temperature is 950 ℃, system III with pressure of 1.5 MPa can lead to the lowest energy consumption (-0.87 MJ/kg).关键词：CO2 capture;Ca and Cu-combined looping;integrated system;emission reduction63|0|0更新时间：2025-02-27 -
摘要：Molecular dynamics simulations, as an important tool for studying microscopic dynamics, have been widely applied in gas hydrate research. The progress on molecular dynamics simulation studies of gas hydrates was summarized, focusing on simulation methods, evaluation parameters, and current applications. The selection of appropriate force field models, ensembles and boundary conditions is critical for accurately simulating the hydrate formation process. Key evaluation parameters include angular order parameters, hydrate cage counts, radial distribution functions, mean square displacement and diffusion coefficients. Molecular dynamics simulations have played a significant role in understanding the nucleation mechanism of hydrates and the mechanism of single additive effects. Future research should further explore the synergistic mechanisms of different hydrate additives and fully utilize molecular dynamics simulations to provide support and guidance for the development of new hydrate additives, thereby enhancing the application level and environmental performance of hydrate-related technologies.关键词：hydrate;nucleation;additives;molecular dynamics98|0|0更新时间：2025-02-27 -
摘要：As a low energy consumption CO2 capture technology, hydrate method has a good application prospect. However, there are still some problems such as slow CO2 hydrates growth rate and low CO2 capture efficiency in CO2 capture by hydrate method. By combining first principles, Monte Carlo simulation and kinetic experiments, the kinetic mechanism and capture performance of carbon nanotubes for CO2 capture from flue gas by hydrate method were studied under low initial pressure (from 0.50 MPa to 4.50 MPa). The results show that for the flue gas with the gas compositions (volume fraction) of 20% CO2 and 80% N2, double-walled carbon nanotubes have preferential adsorption of CO2 through the intermolecular van der Waals force under 0.10 MPa to 0.50 MPa. The CO2 adsorption capacity and CO2 selection rate both reach peak values near 0.80 MPa. Under comprehensive consideration, the compound accelerator system (multi-walled nanotubes mass fraction of 0.01% and tetrahydrofuran mole fraction of 4%) show relative good capture performance under 2.50 MPa, with the gas storage capacity of (3.54 ± 0.28) mmol/mol, the induction time of (24.33 ± 1.53) min and the CO2 capture efficiency of 76.75% ± 5.49%.关键词：CO2 capture;hydrate method;carbon nanotubes;compound accelerator system;kinetic mechanism103|0|0更新时间：2025-02-27
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