燃料对燃烧法制备Ni-Al2O3催化剂结构及浆态床甲烷化催化性能的影响  

Effect of Fuel on Structure and Catalytic Performance for Slurry Methanation over Ni-Al_2O_3 Catalysts Prepared by Combustion Method

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：《高等学校化学学报》2016年第1期134-141,共8页Chemical Journal of Chinese Universities

基　　金：山西省青年基金(批准号:2013021007-4);中国博士后科学基金(批准号:2013M541210);国家“九七三”计划项目(批准号:2012CB723105)资助~~

摘　　要：分别采用浸渍燃烧法和共燃烧法制备了一系列Ni-Al2O3催化剂,并对催化剂进行了表征,研究了燃料种类对不同方法制备的催化剂结构及浆态床CO甲烷化性能的影响.结果表明,以尿素、甘氨酸和乙二醇为燃料时,采用浸渍燃烧法制备的Ni-Al2O3催化剂织构性质均与载体相近,各催化剂金属Ni分散度和Ni晶粒相差不大,甲烷化性能接近,在260℃反应温度下CO转化率在80.1%~83.5%之间.而共燃烧法制备的Ni-Al2O3催化剂受燃烧过程影响明显,以甘氨酸和乙二醇为燃料时制得的催化剂比表面积较小,金属Ni分散度低且Ni晶粒较大,因而甲烷化活性较低;以尿素为燃料制备的催化剂比表面积大且Ni晶粒较小,CO转化率和CH4选择性分别达到84.7%和91.1%.A series of Ni-Al2O3 catalysts was prepared by impregnation combustion method and co-combustion method,and the catalysts were characterized by N2 adsorption-desorption,XRD,TEM,H2-TPR and H2 chemisorption. The effect of fuel type on structure and catalytic methanation performance over Ni-Al2O3 catalysts in a slurry-bed reactor was studied. The results show that Ni-Al2O3 catalysts,prepared by impregnation combustion method using urea,glycine or ethylene glycol as fuel,exhibited similar textural properties,metallic Ni dispersion and Ni crystallite size as those of the support,and the CO conversion was between 80.1% and 83.5% at 260 ℃. However,the Ni-Al2O3 catalysts,prepared by co-combustion method,were significantly affected by the combustion process. The specific surface area of the catalysts prepared using glycine and ethylene glycol as fuel was small,and the metallic Ni dispersion was low and Ni crystallite size was large,which resulted in the low CO conversion. The Ni-Al2O3 catalyst using urea as fuel exhibited the large specific surface area and metallic Ni dispersion and small Ni crystallite size,and the CO conversion and CH4 selectivity reached 84. 7% and 91. 1%,respectively.

关 键 词：浆态床甲烷化 Ni-Al2O3催化剂 浸渍燃烧法 共燃烧法 燃料 

分 类 号：O643.3[理学—物理化学] O614[理学—化学]