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以氢氧化钾、碳酸钠和碳酸氢钠为沉淀剂,采用共沉淀法制备3种铁酸铜催化剂,并对其水煤气变换活性和热稳定性进行了评价。测试发现,以氢氧化钾为沉淀剂制得的催化剂表现出优异的水煤气变换活性。通过X射线粉末衍射仪(XRD)、N2物理吸附(N2-physisorption)、H2-程序升温还原(H2-TPR)、CO2-程序升温脱附(CO2-TPD)和循环伏安法(CV)等技术手段研究了不同的沉淀剂对催化剂的微观结构和表面性质的影响。结果发现,氢氧化钾能有效促进CuFe2O4的生成、抑制CuO和CuFe2O4晶格的长大、促使CuO在催化剂表面的较好分散、增强催化剂的还原能力、增加弱碱性位点的数量。它们显著改善了催化剂的催化活性和热稳定性。
Three kinds of copper ferrite catalysts were prepared by coprecipitation method using potassium hydroxide, sodium carbonate and sodium bicarbonate as precipitants. The water gas shift activity and thermal stability were also evaluated. The test found that potassium hydroxide as a precipitating agent prepared catalyst showed excellent water gas shift activity. The results of X-ray powder diffraction (XRD), N2-physisorption, H2-TPR, CO2-TPD and CV Technical means to study the different precipitants on the catalyst microstructure and surface properties. The results showed that potassium hydroxide can effectively promote the formation of CuFe2O4, inhibit the growth of CuO and CuFe2O4 crystal lattice, promote the better dispersion of CuO on the catalyst surface, enhance the reduction ability of the catalyst and increase the number of weakly basic sites. They significantly improve the catalytic activity and thermal stability of the catalyst.