原位漫反射红外光谱法研究Rh—Mn—Li/SiO_2催化剂的还原过程

Study of Rh—Mn—Li/SiO_2 Catalyst Reduction by in—situ-DR—FTIR

采用原位漫反射红外光谱法研究了Rh—Mn—Li／SiO2催化剂的升温还原过程，结果显示：催化剂在整个还原过程中经历了两个阶段，首先是表面自由水和组分结晶水的脱除，然后是催化剂中硝酸盐组分的分解和氧化物的还原过程。水的脱除主要发生在50-110℃；而氧化物的还原过程主要发生在170℃以后，且在190-330℃温度范围内时还原速度最快，还原反应的主要产物是可分解的或气态的氮化物。实验结果还显示整个还原过程在350℃稳定还原70min后基本结束。

In this paper, in-situ-DR-FTIR technique was employed to investigate the TPR（tempemmre programmed reduction） of Rh-Mn-Li/SiO2 catalyst. The results showed that the whole course of reduction included two processes in which the first was water＇s escaping from the surface of the Rh-Mn-Li/SiO2 catalyst at 50 - 110℃ and the second was the descomposition of nitrate and the reduction of oxide after 170℃ .The reaction products were mainly diffrangible or gasous nitric compounds. And the reaction rate was the highest at the temperature from 190℃ to 330℃. At the same time the experimental results also showed that the whole reduction course almost ended after the catalyst was treated for 70 minutes at 350℃.