热处理对K_2MoO_4-P_(0.2)/SiO_2催化剂结构及性能的影响  

Effect of Heat Treatment on Structure and Performance of K_2MoO_4-P_(0.2)/SiO_2 Catalyst

作　　者：王静[1] 王琪[1,2,3] 陈亚中[1] 郭红彦[1] 鲁骥[1] 崔鹏[1] 

机构地区：[1]合肥工业大学化工学院可控化学与材料化工安徽省重点实验室,安徽合肥230009 [2]合肥工业大学材料科学与工程博士后流动站,安徽合肥230009 [3]安徽六国化工股份有限公司博士后工作站,安徽铜陵244021

出　　处：《石油化工》2013年第9期962-966,共5页Petrochemical Technology

基　　金：国家自然科学基金项目(21106027)

摘　　要：采用等体积浸渍法制备了K2MoO4-P0.2/SiO2催化剂,通过XRD,TG,H2-TPR,XPS方法对催化剂进行了表征,考察了焙烧气氛、焙烧温度对催化剂表面结构及其催化性能的影响。实验结果表明,空气中焙烧的催化剂由于添加剂柠檬酸在焙烧过程中发生燃烧反应,造成局部过热,导致催化剂表面活性物种部分烧结长大,从而降低了催化剂的活性;而在氮气中焙烧的催化剂,由于柠檬酸缓慢分解且形成了还原性气氛,将易还原的Mo-O物种还原,形成了更多的活性Mo物种,且活性组分分散更均匀,从而表现出了比空气中焙烧的催化剂更高的活性。对于甲硫醇合成反应,后者的CO转化率提高约10%,甲硫醇选择性提高约7%。A series of K2MoO4-P0.2/SiO2 catalysts were prepared through incipient wetness impregnation.The effects of calcination atmosphere and temperature on the surface texture and catalytic performance of the catalysts for the synthesis of methyl mercaptan from H2,CO and H2S were investigated.The catalysts were characterized by means of XRD,TG,H2-TPR and XPS.The results showed that the catalysts calcined in air were sintered seriously because of the combustion of the additive citric acid,which caused high local temperature and led to the sintering of active species.In nitrogen atmosphere,the citric acid decomposed slowly,forming a reducing atmosphere,which resulted in the reduction of some easily reducible Mo species,so more active species were generated and the active components were dispersed more uniformly.The conversion of CO and the selectivity to CH3SH on the catalysts calcined in nitrogen atmosphere were about 10％ and 7％ higher than those on the catalysts calcined in air,respectively.

关 键 词：热处理 钼酸钾-磷 二氧化硅催化剂 高硫合成气 甲硫醇 

分 类 号：TQ426.82[化学工程]