H4SiW12O40/SiO2催化正丁醛自缩合反应  

n-Butyraldehyde aldol self-condensation catalyzed by H_4SiW_(12)O_(40)/SiO_2

作　　者：陈翠娜[1] 刘肖红 安华良[1] 赵新强[1] 王延吉[1] 

机构地区：[1]河北工业大学化工学院 绿色化工与高效节能河北省重点实验室,天津300130

出　　处：《化工学报》2014年第6期2106-2112,共7页CIESC Journal

基　　金：国家自然科学基金项目(21076059);天津市自然科学基金项目(12JCYBJC12800);河北省应用基础研究计划重点基础研究项目(12965642D)~~

摘　　要：正丁醛自缩合合成辛烯醛是工业生产辛醇的重要步骤之一。首先考察了3种杂多酸H3PW12O40、H4SiW12O40和H3PMo12O40对正丁醛自缩合反应的催化性能,发现H4SiW12O40的催化性能最好。其次,利用浸渍法制备了负载型H4SiW12O40催化剂,考察了载体和制备条件对催化剂性能的影响,确定以SiO2为载体,H4SiW12O40负载量为50%(质量分数),在150℃焙烧2 h的制备条件。探讨了反应条件对催化剂性能的影响,确定了适宜反应条件:催化剂与正丁醛的质量比为0.15,反应温度120℃,反应时间6 h。在此条件下,正丁醛的转化率为90.4%,辛烯醛的选择性为89.2%。通过对催化剂进行ICP-AES分析和XRD表征,发现活性组分流失是造成催化剂稳定性差的主要原因。为减缓H4SiW12O40的流失,以[emim]BF4离子液体为模板剂,采用溶胶-凝胶法制备了H4SiW12O40/SiO2催化剂,实验结果表明,催化剂稳定性有一定程度的提高。Aldol self-condensation of n-butyraldehyde to 2-ethyl-2-hexenal is one of the important processes for industrial production of 2-ethyl hexanol. Firstly, the catalytic performance of H3PW12O40, H4SiW12O40 and H3PMo12O40 was evaluated and the results showed that H4SiW12O40 presented the best catalytic activity. Secondly, supported H4SiW12O40 catalysts were prepared with the impregnation method and the influence of the kind of support and preparation process parameters on catalyst performance was investigated. The suitable preparation conditions were determined as follows：taking SiO2 as support, loading of H4SiW12O40=50%（mass）, calcination temperature of 150℃ and calcination time of 2 h. The effect of reaction conditions on the catalyst performance of H4SiW12O40/SiO2 was also studied and the suitable reaction conditions was determined as follows：mass ratio of catalyst to n-butyraldehyde 0.15, reaction temperature of 120℃ and reaction time of 6 h. Under the above conditions, the conversion of n-butyraldehyde and the selectivity to 2-ethyl-2-hexenal were 90.4% and 89.2%, respectively. However, the reusability of H4SiW12O40/SiO2 catalyst was poor. Analysis of ICP-AES and XRD demonstrated that the loss of active species H4SiW12O40 was the main reason. In order to decrease the loss of H4SiW12O40, H4SiW12O40/SiO2 catalyst was prepared with the sol-gel method using [emim]BF4 ionic liquid as template. The activity test result showed that the reusability of the prepared catalyst was improved to some extent.

关 键 词：正丁醛 催化剂 羟醛缩合 合成 辛烯醛 多相反应 

分 类 号：TQ032[化学工程]