## 优先发表

, doi: 10.19906/j.cnki.JFCT.2022053

, doi: 10.19906/j.cnki.JFCT.2022068

, doi: 10.19906/j.cnki.JFCT.2022071

, doi: 10.19906/j.cnki.JFCT.2022058

, doi: 10.19906/j.cnki.JFCT.2022054

The complexity and diversity of lignin derived bio-oil (LDB) has posed a great challenge to the subsequent processing and utilization. In this work, HZSM-5 was modified by sodium hydroxide and followed by Ni, Cu and Ru species. LDB was used as the raw biocrude to prepare bio-oil rich in aromatic hydrocarbons with modified HZSM-5 catalysts under supercritical ethanol conditions (320 °C, 14 MPa). Results showed that the desilicated HZSM-5 with the loading of Ni, Cu and Ru (Ni-Cu-Ru/DeHZSM-5) exhibited the best catalytic performance with a high relative amount of aromatic hydrocarbons of 28.95%. After catalytic hydrodeoxygenation (HDO) of LDB, 80.40% upgraded bio-oil (UBO) with 96.32% energy recovery was obtained in the presence of Ni-Cu-Ru/DeHZSM-5. Demethoxylation and dehydration were the main reactions in the catalytic HDO process. Potential reaction pathways of guaiacol, syringol and creosol were also proposed in this paper. The heating value of UBO reached 35.22 MJ/kg compared with LDB, which was increased by 19.80%. The water content and viscosity of UBO were also significantly improved. The micro-mesoporous structure of modified HZSM-5 with loading of Ni, Cu and Ru was beneficial to promote the yield of the aromatic hydrocarbons. The complexity and diversity of lignin derived bio-oil (LDB) has posed a great challenge to the subsequent processing and utilization. In this work, HZSM-5 was modified by sodium hydroxide and followed by Ni, Cu and Ru species. LDB was used as the raw biocrude to prepare bio-oil rich in aromatic hydrocarbons with modified HZSM-5 catalysts under supercritical ethanol conditions (320 °C, 14 MPa). Results showed that the desilicated HZSM-5 with the loading of Ni, Cu and Ru (Ni-Cu-Ru/DeHZSM-5) exhibited the best catalytic performance with a high relative amount of aromatic hydrocarbons of 28.95%. After catalytic hydrodeoxygenation (HDO) of LDB, 80.40% upgraded bio-oil (UBO) with 96.32% energy recovery was obtained in the presence of Ni-Cu-Ru/DeHZSM-5. Demethoxylation and dehydration were the main reactions in the catalytic HDO process. Potential reaction pathways of guaiacol, syringol and creosol were also proposed in this paper. The heating value of UBO reached 35.22 MJ/kg compared with LDB, which was increased by 19.80%. The water content and viscosity of UBO were also significantly improved. The micro-mesoporous structure of modified HZSM-5 with loading of Ni, Cu and Ru was beneficial to promote the yield of the aromatic hydrocarbons.

, doi: 10.19906/j.cnki.JFCT.2023003

, doi: 10.19906/j.cnki.JFCT.2023002

Methyl N-phenylcarbamate (MPC) is an important intermediate for the synthesis of diphenylmethane diisocyanate (MDI), and its preparation using CO2 or its equivalents/derivatives as carbon source represents a green and sustainable manner for fine chemicals synthesis. This review will highlight the development of MPC synthetic methods from the viewpoint of chemical fixation of CO2. The contents mainly include the introduction of MPC synthesis through CO2 equivalents (urea or phenyl urea) alcoholysis, dimethyl carbonate (DMC) aminolysis, and the coupling of DMC and diphenyl urea. Further more, one-pot synthesis of carbamates/MPC from aliphatic amines/aniline, CO2 and alcohols is highlighted which represents one of the most promising schemes in direct CO2 utilization. What is more, the reaction mechanisms and selection of catalysts are also discussed in detail. The advances will provide important theories on further improving the efficiency of green catalysis and sustainable chemical processes. Methyl N-phenylcarbamate (MPC) is an important intermediate for the synthesis of diphenylmethane diisocyanate (MDI), and its preparation using CO2 or its equivalents/derivatives as carbon source represents a green and sustainable manner for fine chemicals synthesis. This review will highlight the development of MPC synthetic methods from the viewpoint of chemical fixation of CO2. The contents mainly include the introduction of MPC synthesis through CO2 equivalents (urea or phenyl urea) alcoholysis, dimethyl carbonate (DMC) aminolysis, and the coupling of DMC and diphenyl urea. Further more, one-pot synthesis of carbamates/MPC from aliphatic amines/aniline, CO2 and alcohols is highlighted which represents one of the most promising schemes in direct CO2 utilization. What is more, the reaction mechanisms and selection of catalysts are also discussed in detail. The advances will provide important theories on further improving the efficiency of green catalysis and sustainable chemical processes.

, doi: 10.19906/j.cnki.JFCT.2022073

, doi: 10.19906/j.cnki.JFCT.2022074

, doi: 10.19906/j.cnki.JFCT.2022092

, doi: 10.19906/j.cnki.JFCT.2022095

, doi: 10.19906/j.cnki.JFCT.2022093

, doi: 10.19906/j.cnki.JFCT.2022089

, doi: 10.19906/j.cnki.JFCT.2022075

, doi: 10.19906/j.cnki.JFCT.2022079

Direct synthesis of liquefied petroleum gas from syngas via Fischer-Tropsch synthesis route was systematically investigated over a nano-level core@shell catalyst. We introduced an incorporation of FeMg catalyst into mesoporous silica shell, with a further modification of Cu particles on the silica surface. The modified Cu/FeMg@SiO2 nano core-shell catalysts were synthesized by the combination of co-precipitation, modified sol-gel and facile impregnation methods. The as-synthesized catalysts’ physicochemical property was characterized by XRD, TEM, N2 adsorption-desorption, H2-TPR, XPS and CO2-TPD techniques. The catalytic performance of Cu/FeMg@SiO2 catalyst shows a high CO conversion of 96.6%, rather low CO2 selectivity of 21.9% and considerable LPG selectivity of 37.9%. The catalytic results indicate that the SiO2 shell restrains the formation of CH4 and contributes to increasing long-chain products. Meanwhile, the enhanced CO conversion of Cu/FeMg@SiO2 was ascribed to the active metal Cu dispersed on SiO2 shell, which also promoteolefin hydrogenation and cracking of C\begin{document}${}^+_5$\end{document} hydrocarbons products. The proposed catalyst preparation method will provide a new strategy for the synthesis of nano level catalyst with combinations of metal- and zeolite-based catalyst. Direct synthesis of liquefied petroleum gas from syngas via Fischer-Tropsch synthesis route was systematically investigated over a nano-level core@shell catalyst. We introduced an incorporation of FeMg catalyst into mesoporous silica shell, with a further modification of Cu particles on the silica surface. The modified Cu/FeMg@SiO2 nano core-shell catalysts were synthesized by the combination of co-precipitation, modified sol-gel and facile impregnation methods. The as-synthesized catalysts’ physicochemical property was characterized by XRD, TEM, N2 adsorption-desorption, H2-TPR, XPS and CO2-TPD techniques. The catalytic performance of Cu/FeMg@SiO2 catalyst shows a high CO conversion of 96.6%, rather low CO2 selectivity of 21.9% and considerable LPG selectivity of 37.9%. The catalytic results indicate that the SiO2 shell restrains the formation of CH4 and contributes to increasing long-chain products. Meanwhile, the enhanced CO conversion of Cu/FeMg@SiO2 was ascribed to the active metal Cu dispersed on SiO2 shell, which also promoteolefin hydrogenation and cracking of C${}^+_5$ hydrocarbons products. The proposed catalyst preparation method will provide a new strategy for the synthesis of nano level catalyst with combinations of metal- and zeolite-based catalyst.

, doi: 10.19906/j.cnki.JFCT.2022082

, doi: 10.19906/j.cnki.JFCT.2022081

, doi: 10.19906/j.cnki.JFCT.2022085

CO2催化加氢是CO2转化利用的有效途径之一。尽管目前CO2加氢在金属氧化物及分子筛复合催化剂上制备异构烷烃及汽油方面已取得显著进展，但仍存在C5 + 烃及C5 + 烃中异构烷烃选择性低，副产物CO选择性高的问题。本文中，我们将锌锆氧化物(ZnZr)与HZSM-5分子筛有效耦合制得系列ZnZr/HZSM-5复合催化剂，分别考察了HZSM-5硅铝比及Zn/Zr比例对复合催化剂上CO2加氢制备C5 + 异构烷烃性能的影响。结果表明，SiO2/Al2O3 = 130，Zn/Zr = 1∶5制得的ZnZr-4/HZSM-5复合催化剂表现出最优的CO2加氢制C5 + 异构烷烃性能，CO2转化率为17%，CO选择性抑制到25%，C5 + 烃及C5 + 烃中异构烷烃选择性分别达60%及89%。而且，该复合催化剂稳定性良好，连续运转120 h未出现失活现象。ZnZr氧化物与HZSM-5分子筛的良好匹配对CO2加氢高选择性合成C5 + 异构烷烃至关重要。 CO2催化加氢是CO2转化利用的有效途径之一。尽管目前CO2加氢在金属氧化物及分子筛复合催化剂上制备异构烷烃及汽油方面已取得显著进展，但仍存在C5 + 烃及C5 + 烃中异构烷烃选择性低，副产物CO选择性高的问题。本文中，我们将锌锆氧化物(ZnZr)与HZSM-5分子筛有效耦合制得系列ZnZr/HZSM-5复合催化剂，分别考察了HZSM-5硅铝比及Zn/Zr比例对复合催化剂上CO2加氢制备C5 + 异构烷烃性能的影响。结果表明，SiO2/Al2O3 = 130，Zn/Zr = 1∶5制得的ZnZr-4/HZSM-5复合催化剂表现出最优的CO2加氢制C5 + 异构烷烃性能，CO2转化率为17%，CO选择性抑制到25%，C5 + 烃及C5 + 烃中异构烷烃选择性分别达60%及89%。而且，该复合催化剂稳定性良好，连续运转120 h未出现失活现象。ZnZr氧化物与HZSM-5分子筛的良好匹配对CO2加氢高选择性合成C5 + 异构烷烃至关重要。

, doi: 10.19906/j.cnki.JFCT.2022084

Efficient utilization of low-temperature coal tar is important for coal pyrolysis or coking. The low-temperature coal tar is rich in phenols with different reactive sites, resulting in a much higher substitution rate (40%) of phenol than high-temperature coal tar and its distillations. In this study, coal tar-based phenolic foam (CPF) was prepared using low-temperature coal tar as raw material to partially replace phenol. The chemical structure, apparent morphology, compressive strength, thermal stability, flame retardancy and thermal insulation properties of CPFs were characterized. The results show that CPFs have similar chemical structures to conventional phenolic foam. Comparing with conventional phenolic foam, the compressive strength of 30%CPF and 40%CPF increases by 18.3% and 55.9%, and the pulverization rate decreases by 22.9% and 50.8%, respectively. The results indicated that toughness was significantly strengthened due to the incorporation of aliphatic structures such as alkylphenols. In addition, the thermal stability of CPFs in the low temperature stage also improves. Although the limited oxygen index of CPFs decreases and thermal conductivity of CPFs increases, they still maintain good flame retardancy and thermal insulation properties. The obtained results prove that low-temperature coal tar can significantly replace phenol to prepare phenolic foam with good performance, which provides a new idea for the high-value utilization of low-temperature coal tar. Efficient utilization of low-temperature coal tar is important for coal pyrolysis or coking. The low-temperature coal tar is rich in phenols with different reactive sites, resulting in a much higher substitution rate (40%) of phenol than high-temperature coal tar and its distillations. In this study, coal tar-based phenolic foam (CPF) was prepared using low-temperature coal tar as raw material to partially replace phenol. The chemical structure, apparent morphology, compressive strength, thermal stability, flame retardancy and thermal insulation properties of CPFs were characterized. The results show that CPFs have similar chemical structures to conventional phenolic foam. Comparing with conventional phenolic foam, the compressive strength of 30%CPF and 40%CPF increases by 18.3% and 55.9%, and the pulverization rate decreases by 22.9% and 50.8%, respectively. The results indicated that toughness was significantly strengthened due to the incorporation of aliphatic structures such as alkylphenols. In addition, the thermal stability of CPFs in the low temperature stage also improves. Although the limited oxygen index of CPFs decreases and thermal conductivity of CPFs increases, they still maintain good flame retardancy and thermal insulation properties. The obtained results prove that low-temperature coal tar can significantly replace phenol to prepare phenolic foam with good performance, which provides a new idea for the high-value utilization of low-temperature coal tar.

, doi: 10.19906/j.cnki.JFCT.2022059

, doi: 10.19906/j.cnki.JFCT.2022070

, doi: 10.19906/j.cnki.JFCT.2022069

Oxidation treated carbon materials for the exploitation of efficient and stable loaded catalysts have been proven to be valid. The surfaces of carbon aerogels (CA) were functionalized with different oxidizing agents, H2O2 and HNO3. A series of Ru-supported catalysts were prepared by impregnation on carbon aerogel (CA) with/without functionalized. The impact of oxidation treatment on the texture features of carbon aerogels, the types and contents of formed surface oxygen-containing functional groups, the metal-support interactions and the Fischer-Tropsch synthesis reaction performance of the catalysts were systematically investigated using XRD, Raman spectra, N2-physisorption, H2-TPR, FTIR and XPS. The experimental results showed that Ru/CA catalyst displayed the highest initial activity but poor stability. In contrast, the Ru/CA-H2O2 catalyst exhibited excellent activity and C5+ selectivity. Characterization results demonstrated that the oxidation treatment increased the carbon aerogels defects, thereby enhanced the specific surface area. The increased content of oxygen-containing functional groups on the surface enhanced the interaction between the support and Ru nanoparticles and improved the stability of the catalyst. Nevertheless, the excessive oxygen-containing functional groups on the surface decrease the activity and C5+ selectivity of carbon aerogels-loaded Ru catalysts. Oxidation treated carbon materials for the exploitation of efficient and stable loaded catalysts have been proven to be valid. The surfaces of carbon aerogels (CA) were functionalized with different oxidizing agents, H2O2 and HNO3. A series of Ru-supported catalysts were prepared by impregnation on carbon aerogel (CA) with/without functionalized. The impact of oxidation treatment on the texture features of carbon aerogels, the types and contents of formed surface oxygen-containing functional groups, the metal-support interactions and the Fischer-Tropsch synthesis reaction performance of the catalysts were systematically investigated using XRD, Raman spectra, N2-physisorption, H2-TPR, FTIR and XPS. The experimental results showed that Ru/CA catalyst displayed the highest initial activity but poor stability. In contrast, the Ru/CA-H2O2 catalyst exhibited excellent activity and C5+ selectivity. Characterization results demonstrated that the oxidation treatment increased the carbon aerogels defects, thereby enhanced the specific surface area. The increased content of oxygen-containing functional groups on the surface enhanced the interaction between the support and Ru nanoparticles and improved the stability of the catalyst. Nevertheless, the excessive oxygen-containing functional groups on the surface decrease the activity and C5+ selectivity of carbon aerogels-loaded Ru catalysts.

, doi: 10.19906/j.cnki.JFCT.2022060

, doi: 10.19906/j.cnki.JFCT.2022094

, doi: 10.19906/j.cnki.JFCT.2023008

, doi: 10.19906/j.cnki.JFCT.2023007

, doi: 10.19906/j.cnki.JFCT.2023006

CH4干重整（DRM）技术能够同时将CH4和CO2两种温室气体转化为合成气，以实现温室气体减排及资源化利用，因此，越来越受到研究者的青睐。生物质炭具有高比表面积、发达的孔隙结构、高的热稳定性、优异的耐酸碱性、丰富的碱/碱土金属和含氧官能团含量以及成本低廉等优点，其应用于DRM，可以适用于页岩气、油田伴生气、焦炉煤气和煤层气等不同的重整体系，省去部分废气的脱硫等预处理过程，具有重要的工业应用前景。本工作对用于DRM的生物质炭基催化剂载体的制备工艺进行了总结。综述了不同的炭化工艺及其对生物质炭产量和性质的影响；介绍了生物质炭的理化性质对重整反应的影响及影响理化性质的因素；分析了不同的活化方法对生物质炭基催化剂催化性能的影响；并对影响催化剂稳定性的碳消耗进行了介绍。 CH4干重整（DRM）技术能够同时将CH4和CO2两种温室气体转化为合成气，以实现温室气体减排及资源化利用，因此，越来越受到研究者的青睐。生物质炭具有高比表面积、发达的孔隙结构、高的热稳定性、优异的耐酸碱性、丰富的碱/碱土金属和含氧官能团含量以及成本低廉等优点，其应用于DRM，可以适用于页岩气、油田伴生气、焦炉煤气和煤层气等不同的重整体系，省去部分废气的脱硫等预处理过程，具有重要的工业应用前景。本工作对用于DRM的生物质炭基催化剂载体的制备工艺进行了总结。综述了不同的炭化工艺及其对生物质炭产量和性质的影响；介绍了生物质炭的理化性质对重整反应的影响及影响理化性质的因素；分析了不同的活化方法对生物质炭基催化剂催化性能的影响；并对影响催化剂稳定性的碳消耗进行了介绍。

, doi: 10.19906/j.cnki.JFCT.2022051

Selective hydrogen combustion (SHC) is a potential technology to improve the energy efficiency and per-pass conversion of light alkane dehydrogenation processes. Exploring SHC catalysts with high selectivity and stability are essential for successful process integration. In the present study, the kinetic behaviour and active sites evolution processes of Pt-based catalysts were investigated. It was found that highly selective hydrogen combustion could be achieved over Sn modified Pt-based catalysts in presence of both propane and propene (over 98%). The stability tests, kinetic study and catalyst characterization revealed that the existence of oxygenated species is the reason for accelerated coking reactions. The formation of graphitized cokes serving as additional unselective active sites and the oxidation of tin in PtSn alloy phases are the primary reasons causing the catalytic selectivity loss during long-run tests under propene-rich condition. Selective hydrogen combustion (SHC) is a potential technology to improve the energy efficiency and per-pass conversion of light alkane dehydrogenation processes. Exploring SHC catalysts with high selectivity and stability are essential for successful process integration. In the present study, the kinetic behaviour and active sites evolution processes of Pt-based catalysts were investigated. It was found that highly selective hydrogen combustion could be achieved over Sn modified Pt-based catalysts in presence of both propane and propene (over 98%). The stability tests, kinetic study and catalyst characterization revealed that the existence of oxygenated species is the reason for accelerated coking reactions. The formation of graphitized cokes serving as additional unselective active sites and the oxidation of tin in PtSn alloy phases are the primary reasons causing the catalytic selectivity loss during long-run tests under propene-rich condition.

, doi: 10.19906/j.cnki.JFCT.2023001

, doi: 10.19906/j.cnki.JFCT.2023004

, doi: 10.19906/j.cnki.JFCT.2023005

CO2的化学转化作为碳减排的有效手段受到了广泛关注，近年来，通过热催化工艺将CO2加氢转化为乙醇已经取得了突破性的进展，但仍然存在乙醇选择性及产率低、副产物较多等问题。本文对热催化CO2加氢制取乙醇的研究进展进行了综述，主要论述了以分子筛、金属氧化物、钙钛矿、二氧化硅、有机框架、金属碳化物等为载体的催化剂的应用，分析了不同金属间的协同作用对CO2转化过程的影响以及各类活性物种的介入对于反应的促进作用，总结了能够有效促进C–C键偶联以及CO2吸附和活化的催化剂体系。在此基础上分析了影响CO2加氢制取乙醇的因素，并对反应机理进行了讨论。综述为CO2加氢制备乙醇的催化剂设计、合成工艺条件优化以及催化机理的探究提供参考。 CO2的化学转化作为碳减排的有效手段受到了广泛关注，近年来，通过热催化工艺将CO2加氢转化为乙醇已经取得了突破性的进展，但仍然存在乙醇选择性及产率低、副产物较多等问题。本文对热催化CO2加氢制取乙醇的研究进展进行了综述，主要论述了以分子筛、金属氧化物、钙钛矿、二氧化硅、有机框架、金属碳化物等为载体的催化剂的应用，分析了不同金属间的协同作用对CO2转化过程的影响以及各类活性物种的介入对于反应的促进作用，总结了能够有效促进C–C键偶联以及CO2吸附和活化的催化剂体系。在此基础上分析了影响CO2加氢制取乙醇的因素，并对反应机理进行了讨论。综述为CO2加氢制备乙醇的催化剂设计、合成工艺条件优化以及催化机理的探究提供参考。

, doi: 10.19906/j.cnki.JFCT.2022072

, doi: 10.19906/j.cnki.JFCT.2022091

The oxophilicity of Co3O4 makes it competent for electrocatalytic oxygen evolution reaction (OER), but its electrocatalytic activity is restricted by the fewer active sites, hindering large-scale application. In this work, a Fe-doped Co3O4 OER electrocatalyst supported by an N-doped hollow nanocage carbon framework (Fe-Co3O4/NC) was successfully prepared by anion exchange and annealing in an air atmosphere strategy. XRD and HRTEM characterizations confirm that Fe the incorporation of Fe into the lattice of Co3O4. XPS characterization clarifies that the valence state of Co increases after the introduction of Fe, which originates from the electrons transfer from Co2 + /Co3 + to Fe3 + and is induced by the valence electron configuration of cations. It simulates Co sites in situ derived into CoOOH active species during the OER process, which is confirmed by the HRTEM and XPS characterization after the OER stability test. Electrochemical performance tests show that the Fe-Co3O4/NC electrocatalyst only exhibits 275 mV overpotential to achieve a current density of 10 mA cm−2 and stably maintains for 20 h at 100 mA cm−2. Together with 20% Pt/C electrocatalyst, the composed two-electrode system only needs 2.041 V applied potential to achieve 100 mA cm−2 for total water splitting in a self-made membrane electrode device, which has industrial application prospects. The oxophilicity of Co3O4 makes it competent for electrocatalytic oxygen evolution reaction (OER), but its electrocatalytic activity is restricted by the fewer active sites, hindering large-scale application. In this work, a Fe-doped Co3O4 OER electrocatalyst supported by an N-doped hollow nanocage carbon framework (Fe-Co3O4/NC) was successfully prepared by anion exchange and annealing in an air atmosphere strategy. XRD and HRTEM characterizations confirm that Fe the incorporation of Fe into the lattice of Co3O4. XPS characterization clarifies that the valence state of Co increases after the introduction of Fe, which originates from the electrons transfer from Co2 + /Co3 + to Fe3 + and is induced by the valence electron configuration of cations. It simulates Co sites in situ derived into CoOOH active species during the OER process, which is confirmed by the HRTEM and XPS characterization after the OER stability test. Electrochemical performance tests show that the Fe-Co3O4/NC electrocatalyst only exhibits 275 mV overpotential to achieve a current density of 10 mA cm−2 and stably maintains for 20 h at 100 mA cm−2. Together with 20% Pt/C electrocatalyst, the composed two-electrode system only needs 2.041 V applied potential to achieve 100 mA cm−2 for total water splitting in a self-made membrane electrode device, which has industrial application prospects.

Gasification is a highly efficient method to deal with direct coal liquefaction residue for syngas production. In this work, to better understand catalytic gasification process of direct coal liquefaction residue rich in sodium species, char structure evolution and behaviors of sodium species during its gasification under CO2 atmosphere were investigated in detail by N2 adsorption, FTIR, XRD, SEM, and Raman analyses. The results show that sodium species developed pore structure of direct coal liquefaction residue during gasification, especially expanded mesoporous structures which increased from 0.05 cm3/g to 0.16 cm3/g at maximum. With the increase of gasification time, different crystalline compounds were formed in chars. Most of the mineral matters identified by XRD were calcium-containing ones, whereas no obvious sodium-containing crystalline compounds were found. This was because that most of sodium species volatilized at high temperature and the crystalline forms of sodium-containing compounds had defects. Compared with sodium species, calcium species were more prone to react with aluminosilicates, which happened to make sodium species remain active during gasification process. The ratio of (GR + VL + VR)/D rose initially and then reduced, which could be explained as the dissociation of the large aromatic and the rearrangement of small aromatic rings into large aromatic structures. Moreover, release ratio of sodium species was closely related with gasification time and 49.8 wt.% of them released in the initial stage of gasification process (within 15 mins). Compared with that of direct coal liquefaction residue reloaded with water-soluble sodium species, the release ratio of sodium species in the original direct coal liquefaction residue was on a lower level (85.2 wt.% versus 89.7 wt.%). Gasification is a highly efficient method to deal with direct coal liquefaction residue for syngas production. In this work, to better understand catalytic gasification process of direct coal liquefaction residue rich in sodium species, char structure evolution and behaviors of sodium species during its gasification under CO2 atmosphere were investigated in detail by N2 adsorption, FTIR, XRD, SEM, and Raman analyses. The results show that sodium species developed pore structure of direct coal liquefaction residue during gasification, especially expanded mesoporous structures which increased from 0.05 cm3/g to 0.16 cm3/g at maximum. With the increase of gasification time, different crystalline compounds were formed in chars. Most of the mineral matters identified by XRD were calcium-containing ones, whereas no obvious sodium-containing crystalline compounds were found. This was because that most of sodium species volatilized at high temperature and the crystalline forms of sodium-containing compounds had defects. Compared with sodium species, calcium species were more prone to react with aluminosilicates, which happened to make sodium species remain active during gasification process. The ratio of (GR + VL + VR)/D rose initially and then reduced, which could be explained as the dissociation of the large aromatic and the rearrangement of small aromatic rings into large aromatic structures. Moreover, release ratio of sodium species was closely related with gasification time and 49.8 wt.% of them released in the initial stage of gasification process (within 15 mins). Compared with that of direct coal liquefaction residue reloaded with water-soluble sodium species, the release ratio of sodium species in the original direct coal liquefaction residue was on a lower level (85.2 wt.% versus 89.7 wt.%).

Single-atom Fe-modified nitrogen-doped carbon (Fe SA/N-C) is an effective alternative to Pt-based carbon for the cathode oxygen reduction reaction (ORR) of fuel cells. Herein, we anchored atomically dispersed Fe–N4 sites on hollow N-doped carbon spheres (Fe SAs/HNCSs-800) for electrocatalytic ORR; the obtained material exhibited electrocatalytic activity and stability comparable to that of commercial Pt/C, with an onset potential of 0.925 V and a half-wave potential of 0.867 V. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy results confirmed the presence of highly dispersed Fe single atoms in Fe SAs/HNCSs-800. The results of experiments and theoretical calculations show that the single-atom dispersed Fe-N4 serve as the ORR active sites, and the adjacent C defects can effectively regulate the electronic structure of Fe atoms and improve the electrocatalytic ORR activity. Single-atom Fe-modified nitrogen-doped carbon (Fe SA/N-C) is an effective alternative to Pt-based carbon for the cathode oxygen reduction reaction (ORR) of fuel cells. Herein, we anchored atomically dispersed Fe–N4 sites on hollow N-doped carbon spheres (Fe SAs/HNCSs-800) for electrocatalytic ORR; the obtained material exhibited electrocatalytic activity and stability comparable to that of commercial Pt/C, with an onset potential of 0.925 V and a half-wave potential of 0.867 V. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy results confirmed the presence of highly dispersed Fe single atoms in Fe SAs/HNCSs-800. The results of experiments and theoretical calculations show that the single-atom dispersed Fe-N4 serve as the ORR active sites, and the adjacent C defects can effectively regulate the electronic structure of Fe atoms and improve the electrocatalytic ORR activity.

, doi: 10.19906/j.cnki.JFCT.2022087

, doi: 10.19906/j.cnki.JFCT.2022090

, doi: 10.19906/j.cnki.JFCT.2022088

, doi: 10.19906/j.cnki.JFCT.2022083

, doi: 10.19906/j.cnki.JFCT.2022086

CO2催化加氢被认为是生产高附加值化学品和燃料最实用的途径之一。然而由于其化学惰性、C–C键偶联过程的高能垒和诸多的竞争反应，因此开发高效的催化剂以促进CO2的活化并转化为多样的化工产物显得至关重要。近年来，氧化铟因具有丰富的氧缺陷位点，在催化CO2加氢方面对甲醇的高选择性以及对CO2转化的高活性引起了人们的广泛关注。本文主要对In2O3的结构及其与氧化物负载或金属元素掺杂的复合催化剂用于催化CO2加氢制备甲醇的催化性能进行了综述。随后又探讨了In2O3与不同类型的分子筛的接近度和元素迁移在CO2加氢制烃类产物中的影响。最后对In2O3基催化剂在CO2选择性加氢方面存在的挑战和发展方向进行了总结。 CO2催化加氢被认为是生产高附加值化学品和燃料最实用的途径之一。然而由于其化学惰性、C–C键偶联过程的高能垒和诸多的竞争反应，因此开发高效的催化剂以促进CO2的活化并转化为多样的化工产物显得至关重要。近年来，氧化铟因具有丰富的氧缺陷位点，在催化CO2加氢方面对甲醇的高选择性以及对CO2转化的高活性引起了人们的广泛关注。本文主要对In2O3的结构及其与氧化物负载或金属元素掺杂的复合催化剂用于催化CO2加氢制备甲醇的催化性能进行了综述。随后又探讨了In2O3与不同类型的分子筛的接近度和元素迁移在CO2加氢制烃类产物中的影响。最后对In2O3基催化剂在CO2选择性加氢方面存在的挑战和发展方向进行了总结。

, doi: 10.19906/j.cnki.JFCT.2022080

, doi: 10.19906/j.cnki.JFCT.2022063

CO2甲烷化反应是一个十分复杂的多相催化过程，在反应过程中会产生各种各样的中间体，其反应路径目前还存在许多争议和矛盾。深入系统地研究CO2甲烷化反应中催化剂表面中间体的演变过程，可以进一步从机理的角度优化催化剂的设计方案，提高催化性能。本文主要基于原位红外光谱表征技术，总结梳理了最近关于CO2甲烷化反应路径研究的相关工作，着重探讨了负载型催化剂的活性金属、载体、助剂、合成方法等因素对CO2甲烷化反应路径的影响以及由此对催化剂性能所产生的积极效果。同时针对现阶段所面临的争论点，即反应气CO2与H2的活化位点、催化剂的活性位点以及未来可行的研究方法进行了详细论述。 CO2甲烷化反应是一个十分复杂的多相催化过程，在反应过程中会产生各种各样的中间体，其反应路径目前还存在许多争议和矛盾。深入系统地研究CO2甲烷化反应中催化剂表面中间体的演变过程，可以进一步从机理的角度优化催化剂的设计方案，提高催化性能。本文主要基于原位红外光谱表征技术，总结梳理了最近关于CO2甲烷化反应路径研究的相关工作，着重探讨了负载型催化剂的活性金属、载体、助剂、合成方法等因素对CO2甲烷化反应路径的影响以及由此对催化剂性能所产生的积极效果。同时针对现阶段所面临的争论点，即反应气CO2与H2的活化位点、催化剂的活性位点以及未来可行的研究方法进行了详细论述。

To explore the catalytic performance of three perovskites (LaBO3--LaCoO3, LaFeO3, LaNiO3), the experimental characterization methods (GC−MS, FT−IR, elemental analysis) and DFT calculation were combined for researching liquefaction of lignin. The effects of time, temperature, catalyst dosage and B cation on the conversion rate, bio-oil yield and bio-oil component distribution were investigated. The results showed that all the three catalysts could promoted the liquefaction of lignin to produce aromatic compounds. Among them, LaCoO3 had the greatest promoting on bio-oil yield, and the highest bio-oil yield of 67.20wt% was obtained at 180 °C for 60 min over 5wt% LaCoO3, followed by LaNiO3 and LaFeO3. The relative content of mono-aromatic compounds reached 89.59% under LaCoO3. Mechanism studies suggested that the adsorption of oxygen atoms on the surface of LaBO3 crystal with lignin reduced the dissociation energy of bonds of lignin. Moreover, LaCoO3 had moderate redox capacity, largest adsorption energy, loose and porous morphology, which could effectively promoted the fracture of C−C and CAr−OCH3 of lignin, so that achieved macromolecular depolymerization and demethoxylation reaction to produce high value-added compounds such as phenol. To explore the catalytic performance of three perovskites (LaBO3--LaCoO3, LaFeO3, LaNiO3), the experimental characterization methods (GC−MS, FT−IR, elemental analysis) and DFT calculation were combined for researching liquefaction of lignin. The effects of time, temperature, catalyst dosage and B cation on the conversion rate, bio-oil yield and bio-oil component distribution were investigated. The results showed that all the three catalysts could promoted the liquefaction of lignin to produce aromatic compounds. Among them, LaCoO3 had the greatest promoting on bio-oil yield, and the highest bio-oil yield of 67.20wt% was obtained at 180 °C for 60 min over 5wt% LaCoO3, followed by LaNiO3 and LaFeO3. The relative content of mono-aromatic compounds reached 89.59% under LaCoO3. Mechanism studies suggested that the adsorption of oxygen atoms on the surface of LaBO3 crystal with lignin reduced the dissociation energy of bonds of lignin. Moreover, LaCoO3 had moderate redox capacity, largest adsorption energy, loose and porous morphology, which could effectively promoted the fracture of C−C and CAr−OCH3 of lignin, so that achieved macromolecular depolymerization and demethoxylation reaction to produce high value-added compounds such as phenol.

, doi: 10.19906/j.cnki.JFCT.2022077

, doi: 10.19906/j.cnki.JFCT.2022067

, doi: 10.19906/j.cnki.JFCT.2022061