溴甲烷制异丁烯催化剂活性中心探索研究  

Investigation on active sites of catalyst for reaction of methyl bromide to isobutylene

作　　者：张信伟[1] 张舒东 李杰[1] 孙晓丹[1] 倪向前[1] 尹泽群[1] 刘全杰[1] 方向晨[1] 

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

出　　处：《天然气化工—C1化学与化工》2017年第4期6-10,89,共6页Natural Gas Chemical Industry

基　　金：中国石油化工股份有限公司资助项目(SH1413)

摘　　要：溴甲烷制异丁烯催化剂在活化过程中依次经历了氧化态、溴化态、还原态的变化。针对这三种状态,分别制备了相应的模型催化剂,采用多种方法表征其性质,并考察了不同状态催化剂的反应性能。研究表明,溴甲烷催化反应产物类型与催化剂的状态和酸性密切相关。氧化态促使溴甲烷转化为二甲醚;溴化态无催化活性;酸性较强的还原态可将溴甲烷转化为低碳烷烃;而富含中强酸的还原态则能高选择性生成异丁烯。其中,溴化态在构建Br-Zn-O复合活性中心过程中具有至关重要的作用,并通过还原处理消除强酸位,为溴甲烷制异丁烯反应的有效进行提供了适宜的酸性。In the process of activation, the catalyst for synthesis of isobutylene from methyl bromide in turn experienced three states： oxidation state, bromination state and reduction state. Aiming at these three states, the corresponding model catalysts were prepared, and their properties were characterized by various methods. The reaction performance of different catalysts was also investigated. The results show that reaction products are closely related to the state and acidity of catalyst. The oxidation state catalyst can directly convert methyl bromide to dimethyl ether. The bromination state catalyst hasn＇t catalytic activity. The reduction state catalyst with strong acid sites can convert methyl bromide to light alkanes, however, the reduction state catalyst rich in medium strong acid sites has the excellent ability to convert methyl bromide to isobutylene with high selectivity. Bromination state plays an important role in building the active site structure of Br-Zn-O. The strong acid sites can be eliminated by reduction, which provides an appropriate catalyst acidity to ensure the reaction of methyl bromide to isobutylene run effectively.

关 键 词：溴甲烷 异丁烯 催化剂 活性中心 酸性 

分 类 号：O643.3[理学—物理化学] TQ032[理学—化学]