摘要
分别采用水热、水热-包覆、球磨法制备了Fe3O4、聚酰亚胺(PI)改性的Fe3O4@PI和Fe3O4-PI催化剂用于费托合成反应,对比研究了PI改性及其含量变化对Fe基催化剂催化CO加氢产物分布的影响规律。结合XRD、SEM、TEM、H2-TPR、COTPD、FT-IR、XPS、TG和接触角实验等手段对催化剂样品进行了表征。结果表明,Fe3O4、Fe3O4@PI和Fe3O4-PI样品均为球形颗粒;PI改性促进了Fe3O4的还原,亲水性增强。Fe3O4@PI样品中,PI均匀包覆于Fe3O4表面,具有较好的热稳定性;与Fe3O4、Fe3O4-PI相比,Fe3O4@PI样品CO吸附增强。在CO加氢反应中,与Fe3O4相比,PI改性的Fe3O4@PI和Fe3O4-PI样品催化活性下降,二次加氢能力受到抑制,烯烃选择性提高;Fe3O4@PI样品烯烃选择性增加明显,烯烷比(O/P)由改性前的0.50提高至2.15;适宜含量的PI改性促进C5+烃生成。
Polyimide(PI) modified Fe3 O4@PI and Fe3 O4-PI catalyst samples were prepared by hydrothermalcoating and ball milling methods,respectively.The effect of PI modification on the product distribution of the Fe-based catalysts for Fischer-Tropsch synthesis was investigated.The catalysts were characterized by XRD,SEM,TEM,H2-TPR,CO-TPD,FT-IR,XPS,TG and contact angle measurements.The results showed that Fe3 O4,Fe3 O4@PI and Fe3 O4-PI were spherical with uniform particle size,and the Fe3 O4@PI particle size was smaller.PI modification promoted the reduction and the hydrophilicity of Fe304.For Fe3 O4@PI sample,PI was uniformly coated on Fe3 O4 surface,which led to good thermal stability.Compared with Fe304 and Fe3 O4-PI samples,CO adsorption was promoted on Fe3 O4@PI.Compared with Fe304,the catalytic activity of Fe3 O4@PI and Fe3 O4-PI decreased,and the secondary hydrogenation ability was inhibited,resulting in increase of olefin selectivity.For Fe3 O4@PI,the olefin selectivity was enhanced significantly with olefin to alkane ratio in C2-4fraction increased from 0.50 to 2.15.PI modification with suitable content favored the formation of C5+hydrocarbons.
作者
马龙
张玉玺
高新华
马清祥
张建利
赵天生
MA Long;ZHANG Yu-xi;GAO Xin-hua;MA Qing-xiang;ZHANG Jian-li;ZHAO Tian-sheng(State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering,Ningxia University,Yinchuan 750021,China)
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2020年第7期813-820,共8页
Journal of Fuel Chemistry and Technology
基金
宁夏重点研发计划(2018BEE03010)
国家自然科学基金(21968025,21965029)项目资助。
