研磨法和浸渍法制备Cu/SBA-15和Cu-ZnO/SBA-15及对甲醇脱氢制甲酸甲酯的催化性能

Catalytic Activity of Methanol Dehydrogenation to MF over Cu/SBA-15 and Cu-ZnO/SBA-15 Prepared by Grinding and Impregnation

以介孔分子筛SBA-15做载体,用研磨法制备Cu/SBA-15-G和Cu-ZnO/SBA-15-G,对它们进行XRD、TEM、TPR和氮气吸附-脱附表征,考察其对甲醇脱氢制甲酸甲酯的催化活性,并与浸渍法制备的Cu/SBA-15-I和Cu-ZnO/SBA-15-I进行对比。实验表明研磨法制备的样品其Cu和ZnO在载体上的分散性比浸渍法的差,其CuO的还原温度明显低于浸渍法的还原温度,加入ZnO能提高产物的选择性。当反应温度为270℃时,研磨法制备的Cu-ZnO/SBA-15-G对甲醇转化率和甲酸甲酯的选择性分别为15.23%和79.81%,浸渍法制备的Cu-ZnO/SBA-15-I对甲醇转化率和甲酸甲酯的选择性分别为13.41%和83.36%。

Using SBA-15 molecular sieve as the support,Cu/SBA-15-G and Cu-ZnO/SBA-15-G catalysts were prepared by grinding.They were characterized by XRD,TEM,TPR and nitrogen adsorption/desorption methods.Their catalytic activities of the methanol dehydrogenation to methyl formate(MF) were studied and compared with those of the catalysts Cu/SBA-15-I and Cu-ZnO/SBA-15-I prepared by impregnation.The results obtained indicated that the Cu and ZnO in the catalysts prepared by grinding had a worse dispersity than that prepared by impregnation.However,the reduction temperature of the CuO in the catalysts prepared by grinding was obviously lower than that prepared by impregnation and the selectivity to MF can be improved by adding ZnO.The experiments showed that the methanol conversion rate and selectivity to MF were 15.23% and 79.81% at 270℃ for Cu-ZnO/SBA-15-G,respectively.For CuZnO/SBA-15-I,the methanol conversion rate and selectivity to MF were 13.41% and 83.36% respectively.