微乳法制备铑基催化剂及C_2含氧化合物的合成

Rh-Based Catalysts Prepared by Microemulsion for Synthesis of C_2-Oxygenates

采用微乳沉积法和微乳浸渍法将纳米Rh粒子负载在纳米硅胶(NS)载体上制成双纳米尺度的Rh/NS催化剂;采用微乳浸渍法制备了Rh-M n/NS催化剂,并用于催化CO加氢合成C2含氧化合物;初步考察了制备条件对Rh-M n/NS催化剂催化CO加氢性能的影响。实验结果表明,相对于普通浸渍法,由微乳技术制备的Rh/NS催化剂的性能较好,采用微乳沉积法制备的Rh/NS催化剂,乙酸收率较高;增加NS载体用量和n(水)∶n(壬基酚聚氧乙烯(5)醚)及延长接触时间可明显提高Rh-M n/NS催化剂对C2含氧化合物的选择性,但活性降低。分析了采用微乳浸渍法制备的Rh-M n/NS催化剂活性很低的原因。

Rh/Nanosilica（NS） catalysts for hydrogenation of CO to C2-oxygenates were prepared by microemulsion deposition and microemulsion impregnation to load nano-Rh particles onto NS support. The obtained catalysts exhibit better activities than that prepared by ordinary impregnation. Yield of acetic acid on Rh/NS catalyst prepared by microemulsion deposition is higher. Mn was added to Rh/NS catalyst as promotor by microemulsion impregnation to improve its catalytic activity. Effect of preparation conditions for Rh-Mn/NS catalyst on CO hydrogenation was investigated. Increasing NS dosage ,prolonging contact time and raising mole ratio of water to surfactant（ polyethylene（5 ）glycol-pnonylphenylether）could improve Rh-Mn/NS catalyst selectivity to C2-oxygenates but lower activity. The reason for poor activity of Rh-Mn/NS catalyst was also analyzed. Further study is necessary to improve activity of Rh-Mn/NS catalyst.