铜锰系高温变换催化剂制备、表征与催化性能

PREPARATION,CHARACTERIZATION AND CATALYTIC PERFORMANCE OF COPPER-MANGANESE HIGH TEMPERATURE SHIFT CATALYST

本文采用湿法共沉淀工艺制备了铜锰高温变换催化剂,利用微反-色谱联合装置考察了催化剂样品的变换活性,利用XRD、TGA-DTA、AA S、粒度分布及孔结构与比表面测定等测试技术对催化剂的物相结构进行了研究.分析了催化剂体相结构和组成对其活性的影响.研究结果表明,催化剂耐热后活性与催化剂的体相组成和微观结构密切相关,当催化剂体相为铜锰1∶2的尖晶石型复合氧化物结构CuM n2O4时,催化剂的粒径相对较小,分布窄,此时铜锰系变换催化剂具有较好的催化性能.因此要使铜锰系高温变换催化剂具有高活性,关键是要在制备过程中创造产生尖晶石相CuM n2O4的生成条件,减少其他杂晶的形成,关键的控制因素是:中和母液体的组成(Cu/M n)、pH和焙烧温度.

Copper-manganese catalysts for high temperature water-gas reaction are prepared by wet-chemical co-precipitation. Catalytic performance of the catalyst samples in a tubular fixed-bed reactor is studied through micro-reaction and online gas chromatography. XRD,TGA-DTA,AAS,et al are used to characterize these samples. The effects of structure ,texture and composition of the catalyst samples on the catalytic performance are investigated. Results show that are effects are definitely significant. When the catalyst is CuMn2O4,with the ratio of Cu ： Mn being 1 ： 2 and the structure being spinel composite oxide,the grain size of the catalyst is relatively small and the distribution of catalyst granularity is relatively narrow,the catalytic activity is higher than in other cases. Therefore, the availability of spinel composite oxideCuMn2O4 is the key to the production of high catalytic activity for high temperature water-gas reaction. While ,the crucial factors for successful preparation of spinel composite oxide CuMn2O4 are Cu/Mn in the mother liquor,PH and the calcinations temperature.