脉冲重量法测镍催化剂的镍表面积和还原镍量

镍催化剂在热重仪内773K还原后,用氮吹扫,降至室温,脉冲进空气,根据增重量算出金属镍的表面积。逐渐升温氧化测得还原镍量。在473K脉冲进CO也可以测得镍表面积。分别用脉冲重量O_2吸附法,脉冲重量CO吸附法,测量了几种负载镍催化剂的镍表面积,并与脉冲色谱O_2吸附法和静态容量H_2吸附法所测结果进行比较。

Pulsed-Gravinsetric determination of nickel surface area and reduced nickel of nicked catalysts

A nickel catalyst was reduced with hydrogen at 773°K in a TG set and then purged with nitrogen. When the temperature of the catalyst was lowered to room temperature, air was pulsed through it. The nickel surface area could be calcuiated from the increased weight of the sample. The amount of reduced nickel could be determined by oxidizing the catalyst at higher temperatures. The nickel surface area also could be measured by using pulsed-gravimetry of CO adsorption at 473°K. Nickel surface areas of four supported nickel catalysts ware measured by pulsed-gravimetry-O adsorption and pulsod-gravimetry-CO adsorption and compared with pulsed-GC-O adsorption and static volume hydrogen adsorption measurements.