研究分子筛催化剂HYI在合成乙酸异龙脑酯反应中的性能,考察焙烧温度、反应温度及颗粒度对催化剂反应性能的影响,在优化反应条件下考察催化剂稳定性.结果表明,在焙烧温度500℃制备的催化剂具有较高的活性、选择性和稳定性,催化剂直径小于2mm条件下,可以消除内扩散对催化剂的影响.在反应温度75℃、常压和莰烯空速0.6h-1条件下,莰烯转化率74％,乙酸异龙脑酯选择性94％,成型催化剂在固定床反应器上连续稳定反应2500h以上.利用N2吸附-脱附、NH3-TPD和TG-DSC对HYI催化剂进行表征,分析催化剂的失活原因,结果表明,催化剂失活主要与反应过程中积炭导致的比表面积和孔容下降有关,催化剂活性可以通过烧焦再生恢复,具有良好的工业应用前景.%The catalytic performance of the zeolite catalyst HYI for the esterification of camphene and acetic acid to isobomyl acetate and the effects of calcination temperature, reaction temperature and grain size on the performance of the catalyst were studied. The catalyst stability was investigated in a fix-bed reactor under the optimum reaction condition. The results indicated that HYI catalyst prepared at calcinic-ition temperature 500 t exhibited high esterification activity, selectivity and stability; the conversion of camphene and the selectivity to isobornyl acetate were 74% and 94% respectively under the condition of reaction temperature 80 t and camphene space velocity 0. 6 h"1. When the particle diameter of the catalyst was smaller than 2 mm, the effect of intraparticle diffusion could be ignored. The catalyst could continiously and stably run for over 2 500 h in the fix-bed reactor. The fresh and deactivated HYI catalysts were characterized by NH3-TPD,N2 adsorption-desorption and TG-DSC in order to know the deactivation causes of the catalyst. The results showed that carbon deposition which reduced the specific surface area and pore volume was the main reason of the catalyst deactivation. HYI catalyst was regenerated by burning the carbon deposition and exhibited good commercial application prospects.
展开▼
