Heteroatom-doped meso/micro-porous carbon materials are conventionally produced by harsh carbonization under an inert atmosphere involving specific precursors,hard/soft templates,and heteroatom-containing agents.Herei...Heteroatom-doped meso/micro-porous carbon materials are conventionally produced by harsh carbonization under an inert atmosphere involving specific precursors,hard/soft templates,and heteroatom-containing agents.Herein,we report a facile synthesis of N and O co-doped meso/micro-porous carbon(NOMC)by template-free carbonization of a small-molecule precursor in a semi-closed system.The semi-closed carbonizaiton process yields hydrophilic NOMCs with large surface area in a high yield.The porous structure as well as the elemental composition of NOMCs can be modulated by changing the holding time at a particular temperature.NOMCs as metal-free heterogeneous catalysts can selectively oxidize benzyl alcohol and its derivatives into aldehydes/ketones with>85%conversion in aqueous solution,which is much higher than that of the control sample obtained in tube furnace(21%conversion),mainly due to their high N content,high percentage of pyridinic N,and large surface area.The presence of O-containing moieties also helps to improve the hydrophilicity and dispersion ability of catalysts and thus facilitates the mass transfer process during aqueous oxidation.The NOMC catalysts also dispayed excellent activity for a wide range of substrates with a selectivity of>99%.展开更多
This article briefly reviewed the advances in the process of the direct oxidation of methane to methanol (DMTM) with both heterogeneous and homogeneous oxidation. Attention was paid to the conversion of methane by t...This article briefly reviewed the advances in the process of the direct oxidation of methane to methanol (DMTM) with both heterogeneous and homogeneous oxidation. Attention was paid to the conversion of methane by the heterogeneous oxidation process with various transition metal ox‐ides. The most widely studied catalysts are based on molybdenum and iron. For the homogeneous gas phase oxidation, several process control parameters were discussed. Reactor design has the most crucial role in determining its commercialization. Compared to the above two systems, aque‐ous homogenous oxidation is an efficient route to get a higher yield of methanol. However, the cor‐rosive medium in this method and its serious environmental pollution hinder its widespread use. The key challenge to the industrial application is to find a green medium and highly efficient cata‐lysts.展开更多
基金supported by National Natural Science Foundation of China(Grant No.51772089 and 21872046)the Youth 1000 Talent Program of China+3 种基金the Outstanding Youth Scientist Foundation of Hunan Province(Grant No.2018JJ1009)the Natural Science Foundation of Hunan Province(Grant No.2020JJ4174)Provincial Science and Technology Innovation Platform and Talent Plan-Changsha,Zhuzhou and Xiangtan High-level Talents Accumulation Project(Grant No.2017XK2023)Research and Development Plan of Key Areas in Hunan Province(Grant No.2019GK2235)
文摘Heteroatom-doped meso/micro-porous carbon materials are conventionally produced by harsh carbonization under an inert atmosphere involving specific precursors,hard/soft templates,and heteroatom-containing agents.Herein,we report a facile synthesis of N and O co-doped meso/micro-porous carbon(NOMC)by template-free carbonization of a small-molecule precursor in a semi-closed system.The semi-closed carbonizaiton process yields hydrophilic NOMCs with large surface area in a high yield.The porous structure as well as the elemental composition of NOMCs can be modulated by changing the holding time at a particular temperature.NOMCs as metal-free heterogeneous catalysts can selectively oxidize benzyl alcohol and its derivatives into aldehydes/ketones with>85%conversion in aqueous solution,which is much higher than that of the control sample obtained in tube furnace(21%conversion),mainly due to their high N content,high percentage of pyridinic N,and large surface area.The presence of O-containing moieties also helps to improve the hydrophilicity and dispersion ability of catalysts and thus facilitates the mass transfer process during aqueous oxidation.The NOMC catalysts also dispayed excellent activity for a wide range of substrates with a selectivity of>99%.
基金supported by the Petrochemical Joint Funds of NSFC-CNPC (U1362202)the Postgraduate Innovation Project of China University of Petroleum (East China) (YCXJ2016030)~~
文摘This article briefly reviewed the advances in the process of the direct oxidation of methane to methanol (DMTM) with both heterogeneous and homogeneous oxidation. Attention was paid to the conversion of methane by the heterogeneous oxidation process with various transition metal ox‐ides. The most widely studied catalysts are based on molybdenum and iron. For the homogeneous gas phase oxidation, several process control parameters were discussed. Reactor design has the most crucial role in determining its commercialization. Compared to the above two systems, aque‐ous homogenous oxidation is an efficient route to get a higher yield of methanol. However, the cor‐rosive medium in this method and its serious environmental pollution hinder its widespread use. The key challenge to the industrial application is to find a green medium and highly efficient cata‐lysts.