钴-钼系催化剂失活的研究 (I)失活催化剂物相和比表面的分析

Study on Co-Mo Spent Catalysts(I):Analyses of Phase and Specific Surface of Spent Catalysts

本文利用X射线衍射和表面孔径测定仪对工业使用后失活的Co-Mo催化剂进行了分析。分析结果表明:失活后的催化剂中主要晶相杂质为FeS、FeSO_4等;与未失活催化剂相比,主要活性相MoS_2晶化明显;钾以K_2SO_4等形式存在;变换炉进空气后造成温度暴涨(T>700℃)使部分K_2SO_4变成K_2S_4O_6相,部分MoS_2蒸发掉。杂质的污染使得催化剂比表面从113m^2/g减小到20m^2/g左右,这是造成Co-Mo系催化剂永久性失活的主要原因之一。

In the paper the Co-Mo spent catalysts in industrial shift reactors were determined by XRD and ST—03 Specific surface analyzer. The results show: The main crystal phases in spent catalysts are FeSO_4 and FeS. Moreover, MoS_2 crystallization is clear. Potassium exists as the form of K_2SO_4. The temperature of catalyst in shift reactors increases and the catalysts crystallizes when air inlets into the catalyst bed. The specific surface reduces to 20m^2/g from 113m^2/g, due to the catalyst is covered with impurity. This is the main cause for the deactivation of Co-Mo shift catalysts.