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合成了分子筛复合超强酸催化剂 Zr O2 - Dy2 O3/SO4 2 - - HZSM- 5;以柠檬酸和正丁醇的酯化反应为探针 ,运用 Hammett指示剂法、 BET、 XRD和 AES等方法 ,考察了催化剂的制备条件与结构性能的关系 .结果表明 ,Dy2 O3与 Zr O2 的质量比为 0 .0 3∶ 1时 ,催化剂性能较好 ;最适宜焙烧温度为 550℃ ,在此温度下制得的催化剂具有较大的比表面积和较强的酸性 ,催化剂中的 Zr O2 以四方晶形存在 ,该催化剂能使柠檬酸的转化率达 97.67% ;反复使用后催化活性下降的主要原因是由于表面积炭 ,在 50 0℃焙烧 2 h后催化活性能基本恢复 .
Synthesis of molecular sieve composite super acid catalyst Zr O2 - Dy2 O3 / SO4 2 - - HZSM-5; citric acid and n-butanol esterification reaction as a probe, using Hammett indicator method, BET, XRD and AES The relationship between the preparation conditions and the structural properties of the catalyst was investigated. The results show that the catalyst has good performance when the mass ratio of Dy 2 O 3 to ZrO 2 is 0. 0 3: 1, and the optimal calcination temperature is 550 ℃. Of the catalyst has a large specific surface area and strong acidity. ZrO2 in the catalyst exists in tetragonal form. The catalyst can make the conversion rate of citric acid reach 97.67%. The main reason for the decrease of the catalytic activity after repeated use is that the surface area carbon , At 50 0 ℃ calcined 2 h catalytic activity recovered.