负载型Fe-Ni纳米合金的制备及其催化丁二烯选择性加氢性能

Synthesis and Catalytic Activity of Supported Fe-Ni Nano-Alloys forButadiene Selective Hydrogenation

采用尿素沉积-沉淀法制备了负载型Fe-Ni纳米合金催化剂,通过调变Fe/Ni摩尔比,研究了金属组分对其还原温度、合金结构及催化丁二烯选择性加氢性能的影响。结果表明:Fe-Ni复合能有效降低Fe、Ni单金属催化剂的还原温度;随着Fe摩尔分数由0增加至100%,金属相结构逐渐由面心立方向体心立方结构转变;在催化加氢过程中,Fe的引入降低了Ni基催化剂活性,但丁烯选择性得到大幅提高;当Fe/Ni摩尔比为25/75时,Fe_(25)Ni_(75)/TiO_(2)-R催化剂中富Ni的Ni3Fe相在丁二烯催化活性(完全转化温度T_(100%)约95℃)和单烯烃选择性(>93%)最佳。

Supported Fe-Ni nano-alloy catalysts were prepared by deposition-precipitation with urea.The impact of Fe-Ni composition on the reduction temperature,alloy structure and selective hydrogenation of butadiene performance were investigated by regulating Fe/Ni molar ratio.The results show that Fe-Ni composition can effectively reduce the reduction temperature of mono-metal catalysts Fe and Ni.As Fe molar fraction increases from 0 to 100%,the structure of metal phase gradually changes from face-centered cubic to body-centered cubic.During catalytic hydrogenation,the introduction of Fe has reduced the activity of Ni-based catalysts,but the selectivity to butenes is greatly improved.When Fe/Ni molar ratio is 25/75,the supported Ni_(3)Fe phase of Ni-rich Fe_(25)Ni_(75)/TiO_(2)-R catalyst exhibits excellent catalytic activity for butadiene(T_(100%)≈95℃)and mono-olefin selectivity(>93%).