放大制备SAPO-34分子筛催化剂,在实验室的流化床反应器中考察其对甲醇制低碳烯烃的催化性能.主要研究了反应温度、空速(WHSV)、进料组成随反应时间对产物中低碳烯烃(乙烯+丙烯)摩尔分率的影响;同时在流化床中,对失活催化剂进行再生实验,考察了再生温度和再生时间的影响,并用XRD、SEM、N2等温吸附/脱附和NH3-TPD手段对催化剂进行表征.实验结果表明,在475℃,空速2.5h-1,甲醇90 ％(mol)进料时,产物中低碳烯烃的摩尔分率高达90 3％;再生温度600℃,再生时间大于30 min条件下催化剂的再生效果较好,且微观结构和强弱酸中心的分布没有发生明显变化,可以循环使用.%In order to study the catalytic performances of scale-up prepared SAPO-34 molecular sieve catalyst for methanol to light olefins, the SAPO-34 was synthesized in the scale-up test device, and then its catalytic performances were investigated in a lab fluidized bed reactor. The effects of reaction temperature, space velocity (WHSV) and feed composition on the molar fraction of ethylene and propylene in the products were investigated. The deactivated catalyst after use was regenerated in the fluidized bed reactor and then the performances of the regenerated catalyst were investigated to find out the optimal regeneration temperature and time. The results indicate that: with feed methanol composition of 90%(mol), the total molar fraction of ethylene and propylene in the products can reach 90.3% under optimal reaction conditions of 475°C, and WHSV=2.5 h"1; the regenerated catalyst performs well after regenerated at 600'C for more than 30 minutes. Both the fresh and the regenerated catalyst SAPO-34 were characterized by XRD, SEM, N2 isothermal adsorption/desorption and NH3-TDP. The results show that the microstructure and the distribution of both strong and weak acid sites of regenerated catalyst SAPO-34 have no evident change, and it can be used repeatedly.
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