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我们研究了镍-铁双金属催化剂在乙酸水蒸气重整制氢反应中的催化性能.研究结果显示单金属铁催化剂对乙酸重整反应活性很低,但是对一氧化碳的中温变换反应有较好的催化性能.镍单金属催化剂对乙酸水蒸气重整制氢反应有非常好的初始催化活性,但是催化剂的长期稳定性很差.镍-铁复合催化剂的低温活性(623 K)和长期稳定性(100 h)都远好于单金属催化剂.这主要是因为铁的加入可以促进镍的分散,形成更多的表面活性位同时有助与防止镍的烧结.我们也对乙酸重整反应中的两个主要气体副产物(一氧化碳和甲烷)的反应路径进行了分析.研究发现反应温度决定一氧化碳和甲烷的反应路径.673 K是一个临界温度.低于此温度,甲烷的产生主要来自于一氧化碳和二氧化碳的甲烷化,而高于673 K,甲烷主要来自于乙酸的直接裂解.对于一氧化碳副产物而言,低于673 K其主要来自于乙酸的裂解或者不充分的水蒸气重整反应,而高于673 K产生的一氧化碳则主要来自与逆水煤气变换反应.
We studied the catalytic performance of nickel-iron bimetallic catalysts in the steam reforming of acetic acid to form hydrogen.The results show that the monometallic iron catalysts have low reactivity to acetic acid reforming, but have a better performance for carbon monoxide mid-temperature shift reaction Catalytic properties of nickel-metal catalysts are very good for steam reforming of acetic acid, but the long-term stability of the catalyst is very poor.The low-temperature activity (623 K) and long-term stability 100 h) are far better than the single metal catalyst.This is mainly because the addition of iron can promote the dispersion of nickel to form more surface active sites help prevent nickel sintering .We also acetic acid reforming reaction in the two (Carbon monoxide and methane) reaction pathways were analyzed.The study found that the reaction temperature determines the reaction path of carbon monoxide and methane .673 K is a critical temperature below this temperature, the methane produced mainly from carbon monoxide and carbon dioxide While above 673 K, methane is mainly derived from the direct cleavage of acetic acid below 673 K for carbon monoxide by-products, which mainly comes from Acetic acid pyrolysis or inadequate steam reforming reaction, and more than 673 K of carbon monoxide generated mainly from the reaction with the reverse water gas shift reaction.