Ag-Pd/C催化四氯化碳液相加氢反应的研究  

Hydrogenation of Carbon Tetrachloride over Ag-Pd/C Catalysts in Liquid Phase

作　　者：孙建芝[1] 张东宝[1,2] 鲁墨弘[1] 李明时[1] 单玉华[1] 朱建军[1] 

机构地区：[1]常州大学化学化工系,江苏常州213164 [2]南通海迪化工有限公司,江苏海门226125

出　　处：《高校化学工程学报》2010年第5期795-800,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金资助项目(20976076);江苏省基础研究计划(自然科学基金)资助项目(BK2009536);教育部留学回国人员科研启动基金资助项目

摘　　要：制备了Ru-Pd/C,Fe-Pd/C,Ni-Pd/C,Cu-Pd/C和Ag-Pd/C催化剂,并考察了它们对四氯化碳液相加氢脱氯成氯仿的反应性能,重点考察了Ag/Pd摩尔比对Ag-Pd/C催化剂反应性能的影响。结果表明,在所有考察的催化剂中,Ag加入到Pd/C可有效抑制副产物甲烷的生成,显著提高氯仿的选择性。在Ag-Pd/C(2:1)催化剂上四氯化碳转化率为100%时,氯仿选择性高达97%。在Ag-Pd合金催化剂中,Ag可能主要起断裂C-Cl键的作用,而Pd主要提供加氢所需的活化H原子。溶剂对Ag-Pd/C催化剂四氯化碳液相加氢脱氯反应的活性和选择性有重要的影响,四氯化碳液相加氢生成CHCl3和CH2Cl2的反应在甲醇溶剂中是平行反应,而在正庚烷溶剂中则是连串反应。A series of Ru-Pd/C,Fe-Pd/C,Ni-Pd/C,Cu-Pd/C and Ag-Pd/C catalysts were prepared and their performances for hydrodechlorination of carbon tetrachloride into chloroform in the liquid phase were investigated.Especially,the effect of Ag/Pd molar ratios on the performances of Ag-Pd/C bi-metal catalysts was studied.It shows that the formation of by-product methane is suppressed by the addition of Ag to Pd/C,and thus the selectivity of chloroform increases significantly.Using catalyst Ag-Pd/C（2：1）,the selectivity of chloroform can up to 97% when the conversion of carbon tetrachloride is near 100%.It is reasonable to propose that the dissociation of C-Cl bond in carbon tetrachloride takes place on the surface of Ag,and the activated H atoms needed are supplied by Pd on the surface of the Ag-Pd alloy.It was found that the performances of Ag-Pd/C catalyst are greatly affected by the solvent.During conducting hydrodechlorination of carbon tetrachloride into CHCl3 and CH2Cl2 over Ag-Pd/C catalyst,parallel reactions were observed when methanol was used as solvent,while sequential reactions were observed when n-heptane was used as solvent.

关 键 词：四氯化碳 加氢脱氯 Ag-Pd/C 摩尔比 溶剂 

分 类 号：O643.38[理学—物理化学] TQ222.214[理学—化学]