We demonstrate for the first time that a short time of microwave irradiation on the oxide precursor of a Cu/ZnO/Al2O3 catalyst can provide unique opportunity for tailoring the microstructure and activity of the cataly...We demonstrate for the first time that a short time of microwave irradiation on the oxide precursor of a Cu/ZnO/Al2O3 catalyst can provide unique opportunity for tailoring the microstructure and activity of the catalyst for methanol steam reforming. It is shown by in situ XRD that a considerable increase in the microstrain of Cu nanocrystals could be achieved in the catalysts processed by microwave irradiation for 310 min, which correlates well with the enhanced CH3OH conversion as observed on the corresponding samples. The present work also confirms that although the high specific surface area of Cu is a prerequisite for catalytic activity, it does not account for the observed changes in activity and selectivity alone without taking bulk microstructural changes into account.展开更多
A number of nanostructured carbon materials were proposed as new effective promoters for preparing modified Cu/ZnO/Al 2O 3 catalyst system for efficient hydrogen production from methanol steam reforming. Compared to t...A number of nanostructured carbon materials were proposed as new effective promoters for preparing modified Cu/ZnO/Al 2O 3 catalyst system for efficient hydrogen production from methanol steam reforming. Compared to the catalysts modified by other type of carbon materials, the ACF-promoted catalyst prepared via carbonate-coprecipitation method exhibit the highest performance in the low-temperature steam reforming of methanol. It was suggested that the intrinsic high surface area nature of ACF material may favor the generation of modified catalysts with a high surface area and improved component dispersion, thus leading to improved performance for methanol steam reforming.展开更多
The effects of reaction temperature,input velocity,molar ratio of methanol to water and reaction time on the conversion of methanol,concentration of carbon monoxide and selectivity of carbon dioxide in the micro-chann...The effects of reaction temperature,input velocity,molar ratio of methanol to water and reaction time on the conversion of methanol,concentration of carbon monoxide and selectivity of carbon dioxide in the micro-channel reactor were investigated.The optimum reaction conditions of micro-channel reactor are as follows:reaction temperature is 260℃,input velocity of methanol liquid is 0.04ml/min and ratio of water to methanol is 1.3.At this reaction conditions,the selectivity of carbon dioxide is 94.3% and conversion of methanol is 52.9%.展开更多
在自制的泡沫金属微结构反应器中,以多孔泡沫镍为载体,负载Cu6Zn3Al0.5Ce0.5/HZSM-5双功能催化剂,用于二甲醚水蒸汽重整制氢的研究。考察负载方法、水醚比、空速、反应温度以及催化剂焙烧温度等条件对二甲醚水蒸汽重整反应的影响。通过...在自制的泡沫金属微结构反应器中,以多孔泡沫镍为载体,负载Cu6Zn3Al0.5Ce0.5/HZSM-5双功能催化剂,用于二甲醚水蒸汽重整制氢的研究。考察负载方法、水醚比、空速、反应温度以及催化剂焙烧温度等条件对二甲醚水蒸汽重整反应的影响。通过X射线衍射(XRD)、程序升温还原(H2-TPR)等手段对催化剂负载方法与催化性能的关系进行探索。结果表明:直接将催化剂Cu6Zn3Al0.5Ce0.5/HZSM-5涂覆在泡沫镍上的催化效果最好,催化剂的最适宜煅烧温度为450℃。在275℃,空速5180 m L/(g·h),水醚比为5的反应条件下,二甲醚转化率和氢收率分别可达99%和95%,反应进行40 h催化剂活性没有明显降低,二甲醚的转化率保持在97%以上。展开更多
文摘We demonstrate for the first time that a short time of microwave irradiation on the oxide precursor of a Cu/ZnO/Al2O3 catalyst can provide unique opportunity for tailoring the microstructure and activity of the catalyst for methanol steam reforming. It is shown by in situ XRD that a considerable increase in the microstrain of Cu nanocrystals could be achieved in the catalysts processed by microwave irradiation for 310 min, which correlates well with the enhanced CH3OH conversion as observed on the corresponding samples. The present work also confirms that although the high specific surface area of Cu is a prerequisite for catalytic activity, it does not account for the observed changes in activity and selectivity alone without taking bulk microstructural changes into account.
文摘A number of nanostructured carbon materials were proposed as new effective promoters for preparing modified Cu/ZnO/Al 2O 3 catalyst system for efficient hydrogen production from methanol steam reforming. Compared to the catalysts modified by other type of carbon materials, the ACF-promoted catalyst prepared via carbonate-coprecipitation method exhibit the highest performance in the low-temperature steam reforming of methanol. It was suggested that the intrinsic high surface area nature of ACF material may favor the generation of modified catalysts with a high surface area and improved component dispersion, thus leading to improved performance for methanol steam reforming.
文摘The effects of reaction temperature,input velocity,molar ratio of methanol to water and reaction time on the conversion of methanol,concentration of carbon monoxide and selectivity of carbon dioxide in the micro-channel reactor were investigated.The optimum reaction conditions of micro-channel reactor are as follows:reaction temperature is 260℃,input velocity of methanol liquid is 0.04ml/min and ratio of water to methanol is 1.3.At this reaction conditions,the selectivity of carbon dioxide is 94.3% and conversion of methanol is 52.9%.
文摘在自制的泡沫金属微结构反应器中,以多孔泡沫镍为载体,负载Cu6Zn3Al0.5Ce0.5/HZSM-5双功能催化剂,用于二甲醚水蒸汽重整制氢的研究。考察负载方法、水醚比、空速、反应温度以及催化剂焙烧温度等条件对二甲醚水蒸汽重整反应的影响。通过X射线衍射(XRD)、程序升温还原(H2-TPR)等手段对催化剂负载方法与催化性能的关系进行探索。结果表明:直接将催化剂Cu6Zn3Al0.5Ce0.5/HZSM-5涂覆在泡沫镍上的催化效果最好,催化剂的最适宜煅烧温度为450℃。在275℃,空速5180 m L/(g·h),水醚比为5的反应条件下,二甲醚转化率和氢收率分别可达99%和95%,反应进行40 h催化剂活性没有明显降低,二甲醚的转化率保持在97%以上。
