溶液燃烧法制备的Ni基催化剂及其浆态床甲烷化催化性能  

Solution Combustion Prepared Ni-Based Catalysts and Their Catalytic Performance for Slurry Methanation

作　　者：吉可明[1] 孟凡会[1] 高源[1] 李忠[1] 

机构地区：[1]太原理工大学,煤科学与技术教育部和山西省重点实验室,太原030024

出　　处：《无机化学学报》2015年第2期267-274,共8页Chinese Journal of Inorganic Chemistry

基　　金：国家"973"计划(No.2012CB723105);山西省青年基金(No.2013021007-4);中国博士后科学基金(2013M541210);太原理工大学校青年团队基金(No.2013T091)资助项目

摘　　要：分别以硝酸铝、硝酸氧锆、硝酸镧和硝酸铈为载体前驱体,与硝酸镍和尿素配制水溶液,采用溶液燃烧法制备了Ni-Al2O3、Ni-ZrO2、Ni-La2O3和Ni-CeO2催化剂,研究了浆态床CO甲烷化催化性能,并进行了低温N2吸附-脱附、XRD、SEM、TEM、H2-TPR和H2化学吸附等表征分析.结果表明,以硝酸铝为前驱体制备Ni-Al2O3催化剂时燃烧火焰稳定且持续时间长,达23 s,样品比表面积（468 m2· g^-1）和金属Ni表面积（10 m2·g^-1）均较大、Ni粒径小（3～5 nm）且分散度高,CO甲烷化催化活性和稳定性好,CO转化率和CH4选择性分别达到94％和95％,在100 h的甲烷化反应中未出现明显失活;以硝酸氧锆和硝酸镧为前驱体制备样品时未出现明显的燃烧火焰,持续时间仅为12s和5s,催化剂比表面积、金属表面积及催化活性均较低;以硝酸铈为前驱体制备样品时燃烧过程迅速而剧烈,样品比表面积（22 m^2·g^-1）和金属Ni表面积（5 m^2·g^-1）小、Ni粒径大且分散性差,甲烷化催化性能最差,CO转化率仅为41％,CH4选择性仅为89％.Ni-Al2O3, Ni-ZrO2, Ni-La2O3 and Ni-CeO2 catalysts were prepared by solution combustion method using AI（NO3）3, ZrO（NO3）2, La（NO3）3 and Ce（NO3）3 （mixed with Ni（NO3）2 and urea in aqueous solution） as the support precursor, respectively. The CO methanation performances of catalysts were studied in slurry-bed reactor, and the catalysts were characterized by low temperature N2 adsorption-desorption, XRD, SEM, TEM, H2-TPR and H2 chemsorption. The results show that the combustion preparation process of Ni-Al2O3 catalyst using Al（NO3）2 as the precursor is stable for long-duration （up to 23 s） and the catalyst has larger surface area （468 m^2·g^-1） and metal surface area （10 m^2·g^-1）, smaller Ni particle （3-5 nm）, excellent dispersion of Ni, and the catalyst has good catalytic performance, whose CO conversion and CH4 selectivity are 94% and 95%, respectively, and no catalyst deactivation is observed in 100 h. The preparation process for catalysts using ZrO（NO3）2 and La（NO3）3 as precursors does not show obvious flame and burning time is also shorter （12 s and 5 s）, the surface areas, metal surface areas and catalytic performances are lower than that of Ni-Al2O3 while that for the catalyst using Ce（NO3）2 as the precursor has high intensity combustion. The catalyst obtained from Ce （NO3）2 precursor shows lower surface area （22 m^2·g^-1） and metal surface area （5 m^2·g^-1）, larger Ni particle and worse dispersion of Ni and the worst methanation catalytic performance with CO conversion and CH4 selectivity of 41% and 89%, respectively.

关 键 词：催化 催化剂制备 浆态床反应器 CO甲烷化 溶液燃烧法 镍催化剂 载体 

分 类 号：O614[理学—无机化学] O643.3[理学—化学]