前体法制备铜锰催化剂及其变换反应催化性能的研究

Copper-Manganese Catalysts Prepared by Precursor Method for Water-Gas Shift Reaction

采用水热法合成出碱式醋酸铜(Cu2(OH)3(OCOCH3).H2O),以碱式醋酸铜为前体,经离子交换、焙烧制得铜锰催化剂.利用XRD、SEM/TEM、FT-IR、TG/DTA、低温氮气吸脱附、TPR等对样品进行表征,并考察了铜锰催化剂在水煤气变换反应中的催化性能.结果表明,所合成的碱式醋酸铜为典型层状化合物,其层间距为0.93 nm,经MnO4-离子交换后,层间距变为0.74 nm.不同焙烧温度的离子交换产物经变换反应后主相均为单质铜,随焙烧温度的升高,铜的结晶度逐渐增加,1 000℃时铜的结晶度减小,1 000℃样品的催化活性显著高于其它温度焙烧的样品,且热稳定性良好.

Using basic copper acetate（Cu2（OH）3（OCOCH3）·H2O） which was prepared by hydrothermal method as Precursor,Copper-Manganese catalysts were prepared by ion exchange and calcinations.The as-prepared catalyst samples were characterized by XRD,SEM/TEM,FT-IR,TG/DTA and low temperature N2 adsorption/desorption,TPR,and tested for water gas shift（WGS） reaction.The results show that the synthesis of basic copper acetate were typical layered compounds and its interlayer distance was 0.93 nm.After MnO-4 exchanging,the interlayer distance became 0.74 nm.The exchanges of products were calcined at different temperatures,which main crystalline phases were Cu after the WGS reaction.With the increased Calcinations temperature,the crystallinity of copper gradually increased,but it decreases at 1 000 ℃.The activity of samples at calcinations temperature of 1 000 ℃ was significantly higher than other calcined samples and its thermal-stability was good.