【作者】 顾海霞；

【导师】 应卫勇；

【作者基本信息】 华东理工大学 ， 化学工艺， 2012， 硕士

【摘要】 以煤或天然气为原料,经由甲醇制低碳烯烃(MTO)的工艺过程,被认为是一条极具魅力的非石油制低碳烯烃的路线。甲醇制低碳烯烃反应催化剂的研究是MTO工艺技术研究领域的重要课题,其中催化剂的放大研究是催化剂工业化进程中的重要阶段,也是必经阶段。论文在中试装置上放大制备了MTO催化剂SAPO-34分子筛,在实验室流化床中考察了其催化性能和再生条件。采用体积为1m3的晶化反应釜放大制备SAPO-34分子筛催化剂,并在实验室反应-再生流化床反应装置中,对甲醇制低碳烯烃反应-再生进行了研究,获得了较佳的反应-再生过程的操作条件。在密相段为Φ30mm×320mm、稀相段为Φ68mm×160mm的流化床反应器中,采用放大制备的SAPO-34分子筛催化剂,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；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对再生催化剂催化性能的影响；用XD、SEM、N2等温吸附/脱附、NH3-TPD等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90wt%进料时,产物中低碳烯烃(乙烯+丙烯)的摩尔分率高达90.3%；再生温度600℃,再生时间90min条件下催化剂的再生效果最好,且微观结构没有发生明显变化,可以循环使用；放大催化剂再现了实验室制备催化剂的良好催化性能。更多还原

【Abstract】 Methanol to olefins process based on coal or natural gas is considered to be the most attractive process to take place of petroleum route process. Research on the catalyst for methanol to olefins is of importance for the methanol to olefins process technology development. And in the process of industrialization of catalyst, investigation of catalyst scale-up preparation is an important stage as well as an essential stage. The paper gives some results about the performances of SAPO-34 molecular sieve catalyst prepared in the test device over methanol to olefins reaction.SAPO-34 molecular sieves are synthesized in autoclave being of lm3 and used as the catalyst for methanol to olefins reaction in the lab’s reaction-regeneration fluidized bed with dimensions ofΦ30mm×320mm for its dense section andΦ68mm×160mm for its thin section. The effects of reaction temperature, space velocity (WHSV) and feed composition on molar fraction of ethylene and propylene are investigated. Meanwhile, the deactivated catalyst is regenerated in the fluidized bed and then the catalytic performances of the regenerated catalyst is studied to decide the optimal temperature and time of the regeneration. Also, the catalyst SAPO-34 and the regenerated catalyst are characterized by means of XRD, SEM, N2 isothermal adsorption/desorption, NH3-TDP, respectively.The results indicate that, under optimal conditions for proceeding operation methanol to olefins:i. e. temperature of 475℃, WHSV of 2.5h-1 and feed methanol composition of 90wt%, the total molar fraction of ethylene and propylene among the products can reach 90.3% which is very close to the molar fraction while the MTO reaction was catalyzed by the lab catalyst SAPO-34, and the regenerated catalyst performs as well as the fresh one when regenerated at 600℃for 90min. Also, the catalyst SAPO-34 and the regenerated catalyst were characterized by means of XRD, SEM, N2 isothermal adsorption/desorption, NH3-TPD. It comes out that, the microstructure and the distribution of the strong and weak acid site have no evident changes. The study shows that pilot-scale SAPO-34 catalyst acts as well as laboratorial SAPO-34 catalyst.更多还原