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首先利用共沉淀沉积法制备CuZnAl催化剂前驱体,并且通过添加聚乙二醇(PEG600)对其进行改性,最后采用完全液相法对前驱体进行热处理制得浆状催化剂,考察了其在浆态床合成气一步法制二甲醚反应中的催化性能,采用X射线粉末衍射、程序升温还原、氨程序升温脱附和X射线光电子能谱对其进行了表征.结果表明,PEG600的添加促进了催化剂中铜组分在热处理过程中被还原成低价铜,提高了催化剂中Cu2O的分散性,改变了催化剂表面酸量和酸强度的分布,同时PEG600的添加方式对催化剂的甲醇合成和甲醇脱水能力有显著影响.在硝酸铜和硝酸锌水溶液中添加0.5 wt%的PEG600时,在热处理过程中形成的Cu2O最稳定,不易被还原,其晶粒度小,进而使CO转化率大幅度提高.
Firstly, CuZnAl catalyst precursor was prepared by coprecipitation deposition method, and its precursor was modified by adding polyethylene glycol (PEG600). Finally, the precursor was treated by heat treatment to obtain slurry catalyst. X-ray powder diffraction, temperature-programmed reduction, ammonia temperature-programmed desorption and X-ray photoelectron spectroscopy were used to characterize the catalytic performance of one-step synthesis of dimethylsulfoxide in the state-bed syngas.The results showed that the addition of PEG600 promoted the formation of The copper component was reduced to copper during the heat treatment to improve the dispersibility of Cu2O in the catalyst and change the distribution of acidity and acid strength on the surface of the catalyst. Meanwhile, the addition mode of PEG600 affected the methanol synthesis and methanol dehydration ability of the catalyst Had a significant effect.When 0.5wt% PEG600 was added into the aqueous solution of copper nitrate and zinc nitrate, the Cu2O formed during the heat treatment was the most stable and not easy to be reduced, the grain size was small, and the CO conversion was greatly increased.