无溶剂法原位合成多级孔Fe@MFI催化剂对费托合成反应性能的影响
|
摘要
采用联合浸渍法-无溶剂法制备了一系列负载型和封装型催化剂,通过XRD、N_2吸附-脱附、NH_3-TPD、SEM和TEM等手段对催化剂进行物化性能表征,并考察了所制备催化剂对合成气直接转化成汽油烃类的反应性能的影响。表征结果显示,采用无溶剂法成功合成了具有MFI骨架结构的Fe@MFI催化剂,Fe粒子较好地封装在沸石内部;催化剂的孔结构和酸中心的协调作用是影响费托合成产物分布的主要因素。实验结果表明,具有多级孔结构的Fe@MFI催化剂展现出良好的汽油选择性,离子交换作用有效改善了H型Fe@HZSM-5催化剂的孔结构和表面酸性,使得汽油和异构烷烃的选择性得到了明显提升。
A series of encapsulated catalysts were prepared by a combination of impregnation and solvent-free method. The physicochemical properties of the catalysts were characterized by XRD,N_2 adsorption-desorption,NH_3-TPD,SEM and TEM techniques,and the reaction performance of as-prepared catalysts on direct synthesis of gasoline-hydrocarbons from syngas was measured as well.These results showed that Fe@MFI catalyst with MFI skeleton structure was successfully synthesized by solvent-free strategy and the iron particles were well encapsulated inside the zeolite cage. The coordination between the pore structure and the acid center of the catalyst was the main factor affecting the distribution of products of Fischer-Tropsch synthesis reaction. The results showed that Fe@MFI catalyst with hierarchical pore structure exhibited good gasoline selectivity. Moreover,for H-type Fe@HZSM-5 catalyst,the selectivity to gasoline and isoparaf?n was signi?cantly improved,due to the fact that the ion exchange effectively improved the pore structure and the surface acidity.
A series of encapsulated catalysts were prepared by a combination of impregnation and solvent-free method. The physicochemical properties of the catalysts were characterized by XRD,N_2 adsorption-desorption,NH_3-TPD,SEM and TEM techniques,and the reaction performance of as-prepared catalysts on direct synthesis of gasoline-hydrocarbons from syngas was measured as well.These results showed that Fe@MFI catalyst with MFI skeleton structure was successfully synthesized by solvent-free strategy and the iron particles were well encapsulated inside the zeolite cage. The coordination between the pore structure and the acid center of the catalyst was the main factor affecting the distribution of products of Fischer-Tropsch synthesis reaction. The results showed that Fe@MFI catalyst with hierarchical pore structure exhibited good gasoline selectivity. Moreover,for H-type Fe@HZSM-5 catalyst,the selectivity to gasoline and isoparaf?n was signi?cantly improved,due to the fact that the ion exchange effectively improved the pore structure and the surface acidity.
引文
[1]Galvis H M,de Jong K P.Catalysts for production of lower olefins from synthesis gas:A review[J].ACS Catal,2013,3(9):2130-2149.
[2]Zhang Qinghong,Kang Jincan,Wang Ye,et al.Development of novel catalysts for Fischer-Tropsch synthesis:Tuning the product selectivity[J].ChemCatChem,2010,2(9):1030-1058.
[3]Cheng Shilin,Mazonde B,Zhang Guihua,et al.Co-based MOR/ZSM-5 composite zeolites over a solvent-free synthesis strategy for improving gasoline selectivity[J].Fuel,2018,223:354-359.
[4]Li Xingang,He Jingjiang,Meng Ming,et al.One-step synthesis of H-βzeolite-enwrapped Co/Al2O3 Fischer-Tropsch catalyst with high spatial selectivity[J].J Catal,2009,265(1):26-34.
[5]Li Wenze,He Yingluo,Li Hangjie,et al.Spatial confinement effects of zeolite-based micro-capsule catalyst on tuned Fischer-Tropsch synthesis product distribution[J].Catal Commun,2017,98:98-101.
[6]Sun Bo,Yu Guobin,Lin Jun,et al.A highly selective Raney Fe@HZSM-5 Fischer-Tropsch synthesis catalyst for gasoline production:One-pot synthesis and unexpected effect of zeolites[J].Catal Sci Technol,2012,2(8):1625-1629.
[7]Javed M,Cheng Shilin,Zhang Guihua,et al.Complete encapsulation of zeolite supported Co based core with silicalite-1shell to achieve high gasoline selectivity in Fischer-Tropsch synthesis[J].Fuel,2018,215:226-231.
[8]Ren Limin,Wu Qinming,Yang Chengguang,et al.Solvent-free synthesis of zeolites from solid raw materials[J].JAm Chem Soc,2012,134(37):15173-15176.
[9]Cheng Shilin,Zhang Guihua,Javed M,et al.Solvent-free synthesis of 1D cancrinite zeolite for unexpectedly improved gasoline selectivity[J].Chem Select,2018,3(7):2115-2119.
[10]Mazonde B,Cheng S,Zhang G,et al.A solvent-free in situ synthesis of a hierarchical Co-based zeolite catalyst and its application to tuning Fischer-Tropsch product selectivity[J].Catal Sci Technol,2018,8(11):2802-2808.
[11]Groen J C,Moulijn J A,Perezramirez J,et al.Desilication:On the controlled generation of mesoporosity in MFI zeolites[J].J Mater Chem,2006,16(22):2121-2131.
[12]Verboekend D,Perezramirez J.Design of hierarchical zeolite catalysts by desilication[J].Catal Sci Technol,2011,1(6):879-890.
[13]Liu Yunqi,Liu Chunying,Liu Chengguang,et al.Sn-modified Pt/SAPO-11 catalysts for selective hydroisomerization of n-paraffins[J].Energy Fuels,2004,18(5):1266-1271.
[14]Deldari H.Suitable catalysts for hydroisomerization of longchain normal paraffins[J].Appl Catal,A,2005,293(1):1-10.
[15]Gopal S,Smirniotis P G.Factors affecting isomer yield for n-heptanehydroisomerization over as-synthesized and dealuminated zeolitecatalysts loaded with platinum[J].J Catal,2004,25(2):278-287.
[2]Zhang Qinghong,Kang Jincan,Wang Ye,et al.Development of novel catalysts for Fischer-Tropsch synthesis:Tuning the product selectivity[J].ChemCatChem,2010,2(9):1030-1058.
[3]Cheng Shilin,Mazonde B,Zhang Guihua,et al.Co-based MOR/ZSM-5 composite zeolites over a solvent-free synthesis strategy for improving gasoline selectivity[J].Fuel,2018,223:354-359.
[4]Li Xingang,He Jingjiang,Meng Ming,et al.One-step synthesis of H-βzeolite-enwrapped Co/Al2O3 Fischer-Tropsch catalyst with high spatial selectivity[J].J Catal,2009,265(1):26-34.
[5]Li Wenze,He Yingluo,Li Hangjie,et al.Spatial confinement effects of zeolite-based micro-capsule catalyst on tuned Fischer-Tropsch synthesis product distribution[J].Catal Commun,2017,98:98-101.
[6]Sun Bo,Yu Guobin,Lin Jun,et al.A highly selective Raney Fe@HZSM-5 Fischer-Tropsch synthesis catalyst for gasoline production:One-pot synthesis and unexpected effect of zeolites[J].Catal Sci Technol,2012,2(8):1625-1629.
[7]Javed M,Cheng Shilin,Zhang Guihua,et al.Complete encapsulation of zeolite supported Co based core with silicalite-1shell to achieve high gasoline selectivity in Fischer-Tropsch synthesis[J].Fuel,2018,215:226-231.
[8]Ren Limin,Wu Qinming,Yang Chengguang,et al.Solvent-free synthesis of zeolites from solid raw materials[J].JAm Chem Soc,2012,134(37):15173-15176.
[9]Cheng Shilin,Zhang Guihua,Javed M,et al.Solvent-free synthesis of 1D cancrinite zeolite for unexpectedly improved gasoline selectivity[J].Chem Select,2018,3(7):2115-2119.
[10]Mazonde B,Cheng S,Zhang G,et al.A solvent-free in situ synthesis of a hierarchical Co-based zeolite catalyst and its application to tuning Fischer-Tropsch product selectivity[J].Catal Sci Technol,2018,8(11):2802-2808.
[11]Groen J C,Moulijn J A,Perezramirez J,et al.Desilication:On the controlled generation of mesoporosity in MFI zeolites[J].J Mater Chem,2006,16(22):2121-2131.
[12]Verboekend D,Perezramirez J.Design of hierarchical zeolite catalysts by desilication[J].Catal Sci Technol,2011,1(6):879-890.
[13]Liu Yunqi,Liu Chunying,Liu Chengguang,et al.Sn-modified Pt/SAPO-11 catalysts for selective hydroisomerization of n-paraffins[J].Energy Fuels,2004,18(5):1266-1271.
[14]Deldari H.Suitable catalysts for hydroisomerization of longchain normal paraffins[J].Appl Catal,A,2005,293(1):1-10.
[15]Gopal S,Smirniotis P G.Factors affecting isomer yield for n-heptanehydroisomerization over as-synthesized and dealuminated zeolitecatalysts loaded with platinum[J].J Catal,2004,25(2):278-287.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |