最新刊期
卷 50 ， 期 4 ， 2025
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摘要：Carbonyl functional groups are widely present in the structures of natural products, pharmaceuticals, agrochemicals, and polymer materials. The development of innovative, efficient and green carbonylation methods is one of the hottest research topics in the field of synthetic chemistry. As important energies and chemical raw materials, alkanes and alkylarenes are widely prevalent in petroleum and natural gas. The highly selective preparation of high value-added carbonyl derivatives through direct carbonylation of C—H bonds, starting from simple alkanes (e.g., cyclopentane, cyclohexane) or alkylarenes (e.g., toluene, ethylbenzene), represents a challenging and promising research area. Among the diverse carbonyl donors, carbon monoxide (CO) is the most extensively utilized carbonylation reagent owing to its 100% atomic efficiency and cost-effectiveness. Based on the significant achievements in the field of radical carbonylation of alkanes or alkylarenes with carbon monoxide over the past fifteen years, the progress on the synthesis of high value-added carbonyl derivatives such as acids, esters, amides (including acyl hydrazides, amides, α-ketoamides, β-lactams and imides) and ketones (including chiral amino ketones) by utilizing peroxide-type compounds or photocatalysts as the initiators, and H2O, H2O2, alcohols, arylsulfinates, azodicarboxylates, amines, imines, amides or olefins as the reaction partners was summarized. Then, the product types of carbonylation reactions were classified and explained, and the substrate scopes and typical reaction mechanisms were discussed. Finally, the challenges and opportunities in the field of radical carbonylation of alkanes and alkylarenes were analyzed and prospected.关键词：alkanes;alkylarenes;carbon monoxide;radical carbonylation;high value-added carbonyl derivatives900|230|0更新时间：2025-04-27 -
摘要：To achieve the goal of “dual carbon” and alleviate environmental pollution, utilization of CO2 has become a focal point in current research. Due to the limitations of CO2 molecular structure and the complexity of hydrogenation routes, the development of highly active and selective catalysts is crucial for achieving high-value utilization of CO2. Supported metal catalysts are widely used in CO2 hydrogenation to CH4/CO reaction due to the advantages of large specific surface area and high dispersion. To enhance the catalytic activity and product selectivity of catalysts, it is essential to understand the role of interfacial modulation in supported metal catalysts during CO2 hydrogenation to CH4/CO reaction. The interfacial structure is influenced by metal structures, carrier properties and metal-carrier interactions, which determine the catalytic performance of catalysts. The thermodynamics and reaction mechanisms of CO2 hydrogenation to CH4/CO were summarized, with a focus on the research progress on supported metal catalysts. The interfacial modulation and future development direction of supported metal catalysts for CO2 hydrogenation to CH4/CO were discussed.关键词：CO2 hydrogenation;interfacial modulation;reaction mechanism;supported metal catalysts353|310|0更新时间：2025-04-27 -
摘要：Cu based catalysts are one of efficient green catalysts for catalytic CO reduction to methanol, and different crystal surfaces of Cu based catalysts exhibit different catalytic performances. Therefore, clarifying the reaction mechanisms on different surfaces is crucial for design and development of catalysts. At present, the reaction mechanisms of stepped Cu(221) surface with the highest stability for CO hydrogenation to methanol are not clear. Based on density functional theory, the optimal pathway for methanol synthesis on the stepped Cu(221) surface was determined via compared activation energies and reaction heats of related elementary reactions. The rate determining step energy barriers during the optimal pathways of methanol synthesis over the terrace Cu(100) and Cu(111) surfaces with higher coordination numbers and stepped Cu(110), Cu(211), Cu(611) and Cu(221) surfaces with lower coordination numbers of Cu active sites were systematically compared (Cu(221): 0.77 eV, Cu(611): 0.88 eV, Cu(211): 0.99 eV, Cu(110): 1.04 eV, Cu(100): 1.05 eV and Cu(111): 1.21 eV). It is confirmed that stepped Cu(221) surface has the best methanol synthesis performance. Combined with Bader charge, density of state, differential charge density and Crystal Orbital Hamiltonian Popution, the CO activation and conversion process was further revealed at the microscopic electronic level. It is found that the strong electrostatic interaction between the step edge site with stronger electronegativity and key species is the essential reason for the high catalytic activity of the stepped Cu(221) surface.关键词：density functional theory;stepped Cu(221) surface;CO activation;methanol;reaction mechanisms470|200|0更新时间：2025-04-27 -
摘要：Isobutylaldehyde, as an important organic chemical raw material, can be synthesized in one-step from methanol and ethanol. Currently, the catalysts used for isobutyraldehyde synthesis are unable to achieve the highly efficient conversion of methanol and ethanol, and selectivity of isobutyraldehyde is relatively low. This has seriously hampered the development of the industrialization of the one-step synthesis of isobutyraldehyde from methanol and ethanol. Hence, there is an urgent need to develop highly efficient and stable catalysts for isobutyraldehyde synthesis. The Cu/SiO2 and xCuMg/SiO2 catalysts were prepared using the ammonia evaporation method. The physicochemical properties of these catalysts were characterized by N2 adsorption/desorption, H2-TPR, CO2-TPD, XRD, XPS and TEM. The impact of different Mg-doping amounts on the performance of the xCuMg/SiO2 catalysts in the one-step synthesis of isobutyraldehyde was investigated. The results show that the Mg-doping not only increases the basic sites on the catalyst surface and the active sites of Cu particles but also enhances the dispersion degree of the active component Cu particles. As a result, it increases the conversion rate of ethanol and the selectivity of isobutyraldehyde. Under the conditions of normal pressure, reduction temperature of 320 ℃, reaction temperature of 360 ℃, liquid hourly space velocity of 1.42 h-1 and V(methanol):V(ethanol) of 10:1, the 1CuMg/SiO2 catalyst exhibits better performance, with the ethanol conversion rate can reach 97.26% and selectivity of isobutyraldehyde is 89.03%. Furthermore, no obvious deactivation is observed after continuous reaction for 200 h, indicating the catalyst has high stability.关键词：CuMg/SiO2 catalyst;methanol;ethanol;isobutyraldehyde;Mg-doping455|255|0更新时间：2025-04-27 -
摘要：As essential feedstocks in the chemical industry, the demand for light olefins is steadily increasing. Cracking of alkanes is one of the main routes to obtain light olefins. The reaction mechanisms (carbocation and free radical mechanisms) involved in the catalytic cracking of alkanes to light olefins were summarized. The research progress of catalysts (molecular sieves, metal oxides, and bifunctional catalysts) utilized for the reaction were analyzed. Furthermore, future directions for the development and optimization of catalysts for alkane catalytic cracking to light olefins were prospected.关键词：alkanes catalytic cracking;light olefins;cracking mechanisms;molecular sieves;bifunctional catalysts848|776|0更新时间：2025-04-27 -
摘要：Adjusting alkaline strength is one of the important methods to improve the transesterification catalytic performances of CaO-based catalysts. ZnO-CaO catalysts with different ZnO mass fractions (xZnO-CaO) were prepared by equal volume impregnation method and applied to transesterification of methyl acetate and propylene glycol methyl ether. The phase compositions and micro-morphologies of xZnO-CaO were characterized by XRD and SEM, etc,. The effects of ZnO mass fractions on xZnO-CaO’s alkaline strengths were studied by CO2-TPD. The transesterification conditions were optimized by single factor analysis method. The results show that the ZnO-CaO catalyst with ZnO mass fraction of 5% (5ZnO-CaO) has suitable alkaline strength and good catalytic performance. Under the conditions of V(methyl acetate)/V(propylene glycol methyl ether) of 10, reaction temperature of 160 °C, catalyst dosage of 0.100 g and reaction time of 2 h, the propylene glycol methyl ether conversion rate and propylene glycol methyl ether acetate selectivity of 5ZnO-CaO are 70.0% and greater than 98.0%, respectively. The conversion of active phase CaO to inactive phase Ca(AC)2 or Ca(AC)2·0.5H2O is the main cause of catalyst deactivation. The deactivated 5ZnO-CaO can be regenerated by roasting, and propylene glycol methyl ether conversion rate of the regenerated 5ZnO-CaO is 69.5% under the above-mentioned reaction conditions.关键词：ZnO-CaO catalysts;transesterification;propylene glycol methyl ether acetate;alkaline strength;catalyst regeneration369|223|0更新时间：2025-04-27 -
摘要：Copper-silicon catalysts exhibit excellent performance in the dehydrogenation of cyclohexanol to cyclohexanone, and reducing the selectivity of by-product phenol is a key research focus of industrial catalysts for cyclohexanol dehydrogenation. Copper-silicon catalysts with different aging time (C-1 (aging time of 0 min), C-2 (aging time of 30 min) and C-3 (aging time of 1 h)) were prepared by precipitation method, and the effect of aging time on the catalytic performance of the catalysts was investigated. The physical and chemical properties of the catalysts were analyzed by XRD, TEM, H2-TPR, FT-IR and N2 physical adsorption/desorption, and their catalytic performances were investigated. The catalyst (C-2) with the lowest phenol selectivity was selected for industrial production and application analysis. The results show that with extension of aging time, the specific surface area and crystallite size of the active component CuO gradually increase, while the pore volume and average pore size initially increase and then decrease. When the aging time is 30 min, strong interaction between CuO and the support SiO2 is formed. In the dehydrogenation of cyclohexanol to cyclohexanone, the conversion of cyclohexanol is over 51.00% and the selectivity of cyclohexanone is over 98.00%. Among them, C-2 exhibits the lowest phenol selectivity (0.7%), and its industrial application in a cyclohexene hydration method for cyclohexanone production plant further confirms its excellent ability to suppress phenol formation. Under the same preparation conditions, adjusting the aging time can modify the accumulation morphology of the active components and metal-support interactions, thereby influencing the selectivity of specific by-products.关键词：copper-silicon catalysts;aging time;physicochemical properties;cyclohexanol dehydrogenation performance;phenol selectivity257|111|0更新时间：2025-04-27 -
摘要：Coke oven gas, as a valuable gaseous resource, is often used as a chemical raw material. However, sulfur impurities such as thiophene (C4H4S) in the gas exhibit strong poisoning effects on catalysts. Industrially, deep removal of thiophene is typically achieved via secondary Ni-Mo hydrodesulfurization. To investigate the effect of metal loading on catalyst performance, NiMo/Al2O3 catalysts with varying NiO contents (5%, 10%, 15% and 20%, mass fraction) were prepared using the impregnation method. The hydrodesulfurization performance of these catalysts in coke oven gas was tested under conditions of reaction temperatures from 250 ℃ to 390 ℃, the pressure of 1 MPa, and the gas hourly space velocity of 4500 h-1. The effects of NiO content on the catalyst performance were analyzed using characterization techniques such as N2 adsorption/desorption, XRD, H2-TPR, and XPS. The results show that in the temperature range of 270 ℃ to 370 ℃, the C4H4S conversion rates of the catalysts decrease in the order of Ni5Mo15/Al2O3, Ni10Mo15/Al2O3, Ni15Mo15/Al2O3 and Ni20Mo15/Al2O3. Among them, the Ni5Mo15/Al2O3 catalyst achieves a C4H4S conversion rate of 70% at 290 ℃ and 90% at 330 ℃, significantly outperforming the other three catalysts. This is attributed to the formation of more active MoS2 species during the presulfurization process, resulting in a higher degree of sulfuration. However, with increasing NiO content, the phenomenon of NiO encapsulating MoO3 likely occurres, resulting in decreased sulfuration and diminished catalytic performance.关键词：NiO content;coke oven gas;thiophene;hydrodesulfurization;NiMo/Al2O3306|274|0更新时间：2025-04-27 -
摘要：The increasingly serious issue of antimony (Sb) pollution makes it crucial to search for an efficient and feasible method to treat Sb-containing wastewater. The Spartina alterniflora and Sycamore bark were used as raw materials to screen for the preferred biochar (FSC300 and FMC400), and EA, N2 adsorption/desorption, SEM, FT-IR and XRD techniques were used to characterize the surface physical and chemical properties of different biochar. The Sb(Ⅲ) adsorption kinetics and isothermal adsorption characteristics of preferred biochar and pristine biochar prepared at corresponding pyrolysis temperature were also studied. The results show that FSC300 has a high surface oxygen content and strong polarity, while FMC400 has a high carbon content and strong aromaticity. Compared to the pristine biochar, the specific surface areas of FSC300 and FMC400 increase by 1.35 and 1.10 times, respectively. FSC300 and FMC400 successfully load Fe3O4 and FeOOH. When the pH value of Sb-containing wastewater is 5 and the biochar dosage is 2.5 g/L, the Sb(III) adsorption capacities of FSC300 and FMC400 increase to 20.81 mg/g and 22.06 mg/g, which are 1.63 and 1.78 times higher than the initial biochar respectively. The adsorption process of Sb(Ⅲ) fits the Langmuir model and quasi-second-order kinetic model, mainly as monolayer chemical adsorption. The adsorption mechanisms include physical adsorption, surface complexation and ion exchange.关键词：antimony pollution;iron-based biochar;Sb adsorption;adsorption mechanism461|538|0更新时间：2025-04-27 -
摘要：The development of highly efficient radioactive iodine adsorption materials is of great significance for the disposal of nuclear waste and the safe utilization of nuclear energy. Two kinds of porous organic polymers were synthesized via Friedel-Crafts alkylation reaction using 2-phenylindole (2-PhIn) and 1-methyl-2-phenylindole (1-Me-2-PhIn) as the building units, formaldehyde dimethyl acetal (FDA) as the external cross-linker and anhydrous FeCl3 as the catalyst. The iodine vapor adsorption properties and structure-activity relationships of the polymers were investigated. It is found that the steric hindrance effect of methyl group has a negative impact on the polymerization process, resulting in polymers with poor pore texture. The iodine adsorption properties of polymers are influenced by both the adsorption sites and the pore structures. 1-Me-2-PhIn-P exhibits a higher iodine adsorption capacity (2.99 g/g), which is superior to commercial activated carbon. During the initial iodine vapor adsorption process, chemisorption plays a dominant role, where I2 interacts with the π-electron-rich polymer framework through Lewis acid/base interactions to form polyiodide anions ( -
摘要：Replacing fossil fuels with renewable energy is crucial for achieving the goals of “carbon peaking and carbon neutrality”.Methanol is an important chemical feedstock, as well as an ideal hydrogen carrier and energy storage medium. The CO2 hydrogenation to methanol technology offers a viable alternative to traditional fossil fuel-based methanol production routes and provides a pathway for CO2 utilization, which is expected to mitigate fossil fuel shortages and environmental pollution. The reactor is one of the core components of CO2 hydrogenation to methanol technology, among which the membrane reactor has advantages of high conversion efficiency and high product selectivity and shows great application potential in this field. The research status of membrane reactors for CO2 hydrogenation to methanol was summarized, and the structural characteristics of methanol synthesis membrane reactors were discussed, and the challenges in their industrial applications were analyzed, and future research directions were explored. This study aims to provide a reference for the industrial application of methanol synthesis membrane reactors.关键词：CO2 hydrogenation;methanol synthesis;membrane reactors410|580|0更新时间：2025-04-27 -
摘要：The coal-to-methanol production process is accompanied by significant carbon dioxide (CO2) emissions. Green hydrogen-coupled coal chemical technology can effectively reduce carbon emissions in coal chemical processes, yet the associated technical challenges and economic benefits have not been adequately assessed. Based on survey data, an accounting system for CO2 emissions in the green hydrogen-coupled coal-to-methanol process was established and the technological competitiveness of green hydrogen coupling under the low-carbon emission context was analyzed. The results indicate that the green hydrogen-coupled coal-to-methanol process, utilizing renewable energy for hydrogen and oxygen production, eliminates the need for the original CO conversion and air separation steps. For a 60 × 104 t/a coal-to-methanol project, the CO2 emissions of the traditional coal-to-methanol process amount to 205.94 × 104 t/a, whereas the green hydrogen-coupled process reduces emissions to 60.94 × 104 t/a, a reduction of approximately 70%. With strong national support for the renewable energy industry and rapid advancement of the energy transition strategy, when the price of green electricity decreases to 0.15 CNY/(kW·h), the cost of green hydrogen-coupled coal-to-methanol production is approximately 2883.33 CNY/t, comparable to the cost of traditional processes. If electricity prices continue to decline and are accompanied by carbon tax implementation, the economic advantages of the green hydrogen-coupled coal-to-methanol process will gradually emerge. This study can provide a reference for achieving net-zero carbon emissions in the coal chemical industry under the “carbon peaking and carbon neutrality” goals.关键词：green hydrogen;coal-to-methanol;carbon reduction;carbon dioxide1212|1194|0更新时间：2025-04-27 -
摘要：Alcohol amine CO2 capture technology is widely used for industrial carbon capture due to its mature technology. However, the emission of absorbents (such as organic amines) and their degradation products affect the CO2 capture efficiency and increase the environmental and health risk. Therefore, it is necessary to control the amine escape from the CO2 capture system by alcohol amine method. The main types of amine escape (physical entrainment, gaseous emission and aerosol emission) were summarized, and the causes and control difficulties of the main amine escape modes were analyzed. The principles, advantages and disadvantages and effects of various amine escape control technologies (multi-stage water washing, acid washing, dry bed, wet electrostatic precipitator, steam injection and mist eliminator, etc.) were compared, and the future direction of amine escape control research was prospected.关键词：alcohol amine CO2 capture technology;aerosol;amine escape;control technologies818|620|0更新时间：2025-04-27 -
摘要：High regeneration energy consumption for CO2 capture by traditional aqueous amine solution is still one of the bottlenecks restricting its wide application in CO2 capture field. In order to reduce the regenerative energy consumption of the absorbent, an energy-efficient amino acid solution solid-liquid phase change absorbent was proposed. Potassium L-threonine solutions (PL-T) with different concentrations were prepared as the solid-liquid phase change absorbent. The CO2 absorption and desorption processes of PL-T were investigated, and the absorption and desorption rates, reaction heat and sensible heat were evaluated. The results show that under absorption and desorption temperatures of 313K and 363 K, respectively, the absorption and desorption rates both reach the maximum values with PL-T concentration of 4 mol/L, which are 2.20 × 10-5 mol/s and 1.43 × 10-4 mol/s, respectively. Under 313 K, the reaction heat of 5 mol/L PL-T with CO2 is -80.94 kJ/mol, and its absolute value is less than the corresponding value (-88.22 kJ/mol) of 5 mol/L monoethanolamine solution, leading to a lower desorption energy consumption. When only solid precipitate of 5 mol/L PL-T is desorbed, its sensible heat can be reduced by 51.4%, compared to 5 mol/L MEA.关键词：CO2 capture;solid-liquid phase change absorbent;amino acid salt;regeneration energy;absorption heat;sensible heat428|408|0更新时间：2025-04-27 -
摘要：Chemical absorption is an important CO2 capture technology, among which water-lean absorbent has been widely studied due to their advantages of fast capture rate, high CO2 absorption capacity and low regeneration energy consumption, etc. Chemical absorbent based on 1,3-diaminopropane (DAP)/tetramethylethylenediamine (TMEDA)/H2O exhibits excellent CO2 capture performance, while the amine water-lean absorbent prepared by replacing part of H2O with physical solvent can further reduce regeneration energy consumption. Amine water-lean absorbent DAP/TMEDA/DMEDEG/H2O was prepared by the addition of diethylene glycol dimethyl ether (DMEDEG) to DAP/TMEDA/H2O. Effect of m(DMEDEG):m(H2O) on the CO2 absorption and desorption performance of DAP/TMEDA/DMEDEG/H2O was investigated. Nuclear magnetic resonance (NMR) and quantum chemical calculation were used to analyze the reaction and phase-separation mechanisms of DAP/TMEDA/DMEDEG/H2O. Additionally, the corrosiveness and regeneration energy consumption of DAP/TMEDA/DMEDEG/H2O were studied. The results show that by fixing the DAP + TMEDA mass fraction in DAP/TMEDA/DMEDEG/H2O at 50%, DAP/TMEDA/DMEDEG/H2O exhibits the maximum CO2 cyclic load (3.549 mol/kg) with m(DMEDEG):m(H2O) of 1:9. The reaction between DAP and CO2 mainly produces carbamate (DAPCOO-), and the intermediate product (DAP+COO-) facilitates the protonation of TMEDA. After 7 d of corrosion of 20# carbon steel sample under certain conditions, the corrosion rate of DAP/TMEDA/DMEDEG/H2O is -1.035. Under certain conditions, the regeneration energy consumption of DAP/TMEDA/DMEDEG/H2O (approximately 4.13 GJ/t) is slightly lower than the regeneration energy consumption (approximately 4.20 GJ/t) of monoethanolamine with mass fraction of 30%.关键词：water-lean amine absorbent;CO2 capture;diethylene glycol dimethyl ether;phase separation mechanism;regeneration energy450|242|0更新时间：2025-04-27 -
摘要：Formic acid is colorless, low toxicity, easy to store and transport, and can be produced by CO2 hydrogenation and biomass conversion, which is an ideal hydrogen carrier. As an active metal, Pd has high catalytic activity in formic acid dehydrogenation, but the Pd-based heterogeneous catalysts are still facing the problems of low catalytic activity and selectivity, poor stability and expensive, which cannot meet the needs of industrialization. In order to solve these problems, the research progress of Pd-based heterogeneous catalysts for the liquid-phase dehydrogenation of formic acid in recent years was reviewed, and the reaction mechanism of liquid phase dehydrogenation of formic acid was discussed, as well as the effects of key factors of liquid phase dehydrogenation of formic acid (Pd nanoparticles (Pd NPs) size/microstructure, carrier structure/surface properties and reaction additives) on the catalytic activity and stability were discussed. It is found that the alloying, core-shell structure, pore confinement effect of porous materials, amino functionalization/nitrogen doping modification of carrier surface and metal oxide defect effect, etc. could obtain Pd NPs with smaller sizes, then improve the dispersion and stability of Pd NPs and reduce the amount of Pd, and at the same time adjust and optimize the microstructure of Pd NPs, resulting in the improvement of the activity and stability of the catalysts for the dehydrogenation of formic acid, which can provide useful reference for the development of novel Pd-based heterogeneous catalytic systems for the efficient dehydrogenation of formic acid.关键词：hydrogen;formic acid dehydrogenation;Pd-based catalysts;heterogeneous catalysts;reaction mechanism387|218|0更新时间：2025-04-27 -
摘要：External temperature-controlled cylindrical solid hydrogen storage tanks have advantages of simple structure, low cost, easy mass production, and series parallel combination applications. The hydrogen absorption and desorption performance of two cylindrical hydrogen storage tanks with different aspect ratios were tested and analyzed by a self-designed solid-state hydrogen absorption and desorption performance testing device. The aim is to evaluate the actual utilization of their theoretical hydrogen storage capacity and investigate influence of parameters such as hydrogen absorption and desorption temperature and pressure on their hydrogen absorption and desorption performance. The results show that under different hydrogen absorption and desorption conditions, the hydrogen absorption and desorption rate of the two experimental storage tanks exhibites a three-stage characteristic of “short-term steep rise, short-term steep fall and slowly approaching zero”, while the cumulative hydrogen absorption and desorption amount shows a two-stage characteristic of “short-term steep rise and slow climb” over time. The hydrogen absorption time in the “short-term steep rise” stage accounts for less than 2% of the total hydrogen absorption time. The maximum hydrogen absorption rate in this stage is 6.545 L/s, and the hydrogen absorption rate in the “slowly approaching zero” stage is less than 0.5 L/s. Due to incomplete activation of the alloy bed and insufficient heat transfer in the core, within the operating range of this article, the hydrogen absorption saturation is less than 60%, and the reversible hydrogen desorption rate can reach over 90%. When the initial temperature of the bed remains constant, both the total hydrogen absorption and release time and the cumulative hydrogen absorption and release amount increase with the increase of the initial pressure difference. When the initial hydrogen absorption and desorption pressure remains constant, the total hydrogen absorption time, cumulative hydrogen absorption amount, and hydrogen absorption saturation are all negatively correlated with the initial temperature of the alloy bed, while the total hydrogen release time, cumulative hydrogen release amount, and reversible hydrogen release rate are positively correlated with the initial temperature of the bed. Appropriately increasing the aspect ratio can significantly improve the comprehensive heat transfer efficiency, thereby significantly enhancing the hydrogen absorption and desorption performance.关键词：solid state hydrogen storage;hydrogen absorption and desorption performance;hydrogen absorption saturation;reversible hydrogen release rate308|425|0更新时间：2025-04-27
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