摘要
以ZSM-5分子筛(n(Si)/n(Al)=360)为催化剂,在固定床反应器上考察了反应温度、水醇比、原料空速和反应时间对甲醇制低碳烯烃(MTO)各产物选择性的影响。结果表明:随反应时间增加,丙烯的选择性逐渐增大,乙烯的选择性先增大后减小,所有产物的选择性均在6.5h后趋于稳定;随反应温度升高,低碳烯烃的选择性先增大后减小;原料中适量掺杂水对反应有利,n(水)/n(醇)为2时,低碳烯烃的选择性最高;空速增加,低碳烯烃的选择性逐渐下降,但空速过低催化剂易积炭失活。最佳反应条件确定为:430℃,LHSV=2.2h-1,n(水)/n(醇)=2,此时乙烯+丙烯的选择性达69.36%,其中丙烯的选择性为53.54%。
Effects of reaction conditions,including temperature,feed ratio of water to methanol,space velocity and time on stream,on the selectivities of products in the conversion of methanol to olefins over the catalyst ZSM-5 zeolite（n（Si）/n（Al）=360） in a fixed bed reactor were investigated.The results showed that with the increase of time on stream,the selectivity to propylene increased,the selectivity to ethylene first increased and then decreased,and the selectivities of all products tended to be stable after reaction for 6.5 hours;with the increase of reaction temperature,the selectivities to ethylene and propylene first increased and then decreased;adding appropriate amount of water in the feedstock was beneficial to the reaction,and the highest selectivity to ethylene and propylene was obtained at the molar ratio of water to methanol of 2;with the increase of LHSV,the selectivity to ethylene and propylene decreased,but low space velocity caused easily the coke deposition and deactivation of the catalyst.The optimum reaction conditions were determined as follows： 430℃,LHSV of 2.2h-1,molar ratio of water to methanol of 2,under above conditions the selectivity to ethylene and propylene was up to 69.36%（53.54% propylene ＋ 15.82% ethylene）.
出处
《天然气化工—C1化学与化工》
CAS
CSCD
北大核心
2013年第3期28-33,共6页
Natural Gas Chemical Industry
基金
贵州省工业攻关项目(黔科合GY字2012-3057)
贵阳市科技局(筑科合同2012101-25)
贵州赤天化集团有限责任公司产学研合作项目
