碱金属修饰的MoVTeO_x/SiO_2上异丁烷选择氧化制MAL反应研究  

Effect of Alkali Metal Doping on the Performance of Silica-supported MoVTeO_x Catalysts for Selective Oxidation of Isobutane to Methacrolein

作　　者：孙晓丹[1] 金浩[1] 张舒冬[1] 张信伟[1] 尹泽群[1] 刘全杰[1] 翁维正[2] 万惠霖[2] 

机构地区：[1]中国石油化工股份有限公司抚顺石油化工研究院,辽宁抚顺113001 [2]固体表面物理化学国家重点实验室醇醚酯化工清洁生产国家工程实验室厦门大学化学化工学院,福建厦门361005

出　　处：《当代化工》2013年第1期9-13,共5页Contemporary Chemical Industry

摘　　要：采用常规浸渍法制备了相同含量碱金属(Li、Na、K和Cs)修饰的负载型MoV0.8Te0.23MmOx/SiO2催化剂,在对催化剂进行异丁烷选择氧化制甲基丙烯醛(MAL)反应性能评价的基础上,采用BET、XRD、Raman和H2-TPR等表征技术分别考察了催化剂的比表面积、相结构、表面氧物种和可还原性等,并将实验结果与催化剂的性能进行了关联。研究表明:在反应温度为420℃时,Cs与Mo摩尔比为0.2的催化剂上MAL的收率最高;经Cs修饰的3%MoV0.8Te0.23Ox/SiO2催化剂中出现了晶相TeO2物种,在反应过程中,TeO2中的Te-O活性位被还原后能快速得到体相晶格氧的补充,从而促进晶格氧的传递。Based on 3% MoV0.8Te0.23Ox /SiO2 catalyst,effect of alkali metal（Li,Na,k,Cs） doping on its catalytic performance was investigated.Alkali-free and alkali-doped MoV0.8Te0.23Ox /SiO2 catalysts were characterized by BET,XRD,Raman and H2-TPR.In addition,the relationship between characterization results and catalytic performance was also studied.The results show that the highest MAL yield can be obtained on the catalyst with Cs/Mo molar ratio of 0.2 at the reaction temperature of 420 ℃.The enhanced catalytic performance in the selective oxidation of isobutane to MAL on the Cs-doped catalyst seems to be related to the crystalline TeO2 species appearing on the catalyst,the Te-O active site of which can be supplied with bulk lattice oxygen fast after reduction,which can promote the delivering of lattice oxygen.

关 键 词：异丁烷 碱金属 甲基丙烯醛 铯 

分 类 号：TQ426[化学工程]