摘要
采用沉淀法制备了经Al、Cr、Cu和Zn等掺杂的Ni/SiO2催化剂,用于甘油与乙二胺固定床气相催化缩环制2-甲基吡嗪(2-MP),并详细考察了催化剂焙烧温度、反应温度、载气空速和原料液水含量对缩环反应的影响。结果表明,ZnO物种可使Ni/SiO2催化剂同时具有适量的酸位与碱位,有助于甘油与乙二胺分子的活化,从而使2-MP的收率得以提高;焙烧温度对Ni-Zn/SiO2催化性能的影响较为重要,500℃最佳;Ni-Zn/SiO2催化甘油与乙二胺缩环反应的最佳工艺条件为:反应温度为380℃、载气N2空速150 h-1、原料液中水质量分数为70%,此时甘油与乙二胺的转化率均为100%,2-MP收率为66.4%。
Ni/SiO2 catalysts modified by Al, Cr, Cu and Zn were prepared by precipitation and applied in the fixed-bed gas-phase catalytic cyelization of ethanediamine （EDA） with glycerol to give 2- methylpyrazine（2-MP） in the present work. And at the same time, the effects of calcination and reaction temperature, GHSV and water content on the catalytic properties of Ni-Zn/SiO2 in cyclization were also investigated. The results indicate that the presence of ZnO led to the simultaneous production of acidic and alkali sites over Ni-Zn/SiO2, which was helpful to the activation of EDA and glycerol molecules and 2-MP formation through cyclization was improved. It was also found that the calcination temperature was an important factor in affecting the catalytic property of catalysts in eyelization. And Ni-Zn/SiO2 calcined at 500 ℃ exhibited the highest 2-MP yield of 66.4% along with complete conversion towards glycerol reaction conditions ： reaction and EDA was obtained over temperature 380℃, GHSV of Ni-Zn/SiO2 catalyst under the optimum carrier N2 150 h^-1, water content in the reaction liquid 70%.
出处
《精细化工》
EI
CAS
CSCD
北大核心
2014年第6期801-806,共6页
Fine Chemicals
基金
四川省杰出青年学术技术带头人培育计划项目(2012JQ0047)
"大气环境模拟与污染控制"四川省高校重点实验室自主课题(ZZKT2012003)~~
关键词
甘油
生物柴油副产物
催化缩环
2-甲基吡嗪
glycerol
biodiesel by-product
catalytic cyclization
2-methylpyrazine
