摘要
以高频感应炉制备了熔铁催化剂，并进行了K2CO3溶液处理，采用ICP、XRD和H2-TPR等手段，对费托合成熔铁催化剂的物相与组成进行表征。于固定床积分反应器中进行催化剂的费托合成性能评价，反应条件为220℃-350℃，2.0MPa， V（H2）/V（CO）=2，GHSV=3000h-1。结果表明，由于石墨坩埚的使用，使得感应炉制备的熔铁催化剂中引入了大量的Si和Al元素，这些元素与铁氧化物形成固熔体，造成催化剂难以被还原、表面碱度严重被削弱、产物以低碳烃为主。经K2CO3溶液处理后，催化剂中固熔体部分被溶解，还原难度逐步降低。同时，随着K2CO3溶液浓度的增加，催化剂的表面碱度逐渐增强，产物中CH4选择性由44.82%降到28.82%， C2-C4烯烃选择性也逐渐增加。
Fused iron catalysts for Fischer-Tropsch synthesis （FTS）were prepared by induction furnace and then treated with K2CO3 aqueous solution. ICP, XRD and H2-TPR were used to the catalysts, and the FTS performances of the catalysts were investigated in a fixed-bed reactor under the conditions of 220 ℃-350 ℃, 2.0 MPa, H2/CO mole ratio of 2, GHSV of 3000h-1. The results showed that Al and Si introduced from graphite crucible reacted with iron oxide to form solid solution, which severely suppressed the reduction and surface basicity of catalysts and brought high C2-C4 selectivity in FTS. After treatment with K2CO3 aqueous solution, the solid solution was partly dissolved and the extent of reduction gradually increased. As the concentration of K2CO3 aqueous solution increased, surface basicity of catalysts enhanced, which made CH4 selectivity decreased from 44.82% to 28.82%and C2-C4 olefins selectivity improved.
出处
《天然气化工—C1化学与化工》
CAS
CSCD
北大核心
2014年第3期48-52,共5页
Natural Gas Chemical Industry
基金
国家自然科学基金资助项目(21373254)
武汉凯迪工程技术研究总院有限公司资助项目(2013WT101)
煤转化国家重点实验室自主研究课题资助项目(2013BWZ004)
关键词
费托合成
熔铁催化剂
感应炉
固熔体
碳酸钾溶液
Fischer-Tropsch synthesis
fused iron catalyst
induction furnace
solid solution
potassium carbonate solution
