B_2O_3负载量对MoO_3/CeO_2-Al_2O_3耐硫甲烷化性能的影响  

Impact of B_2O_3 loading on sulfur-resistant methanation activity of MoO_3/CeO_2-Al_2O_3 catalyst

作　　者：刘震[1] 王保伟[1] 王玮涵[1] 孟大钧 李振花[1] 马新宾[1] 

机构地区：[1]天津大学化工学院绿色合成与转化教育部重点实验室,天津300072

出　　处：《化工学报》2016年第9期3672-3677,共6页CIESC Journal

基　　金：国家高技术研究发展计划项目(2015AA050504)~~

摘　　要：考察B_2O_3负载量对于MoO_3/CeO_2-Al_2O_3催化剂对耐硫甲烷化活性的影响,利用BET、XRD、TEM、NH3-TPD等手段对催化剂进行了表征。结果表明,催化剂的耐硫甲烷化活性随B_2O_3负载量增加呈现先升高后降低的变化规律;当B_2O_3负载量为0.5%时,催化剂的耐硫甲烷化活性最高,CO转化率达到55%。结合表征分析,发现添加B_2O_3会影响催化剂载体的结构和表面酸度,从而影响活性组分的分散程度,进而影响MoO_3/CeO_2-Al_2O_3催化剂的耐硫甲烷化性能。催化剂的晶化程度太高或单位面积上的强酸量太多均不利于甲烷化反应;较好的活性组分分散度有利于催化剂甲烷化活性的提高。Synthetic natural gas（SNG） production from coal is considered again due to rising prices for natural gas, the wish for less dependency from natural gas imports and the opportunity of reducing green house gases. The technical, economic and ecological feasibility of SNG with Mo-based catalysts showed water-gas shift and sulfur-resistant methanation has been studied. In this paper the impact of B_2O_3 loading on the MoO_3/CeO_2-Al_2O_3 catalysts for sulfur-resistant methanation was investigated. The catalysts were prepared by impregnation method and characterized by means of BET, XRD, TEM and NH3-TPD. The results showed that the sulfur-resistant methanation activity of Mo O3/CeO_2-Al_2O_3 catalysts were increased at first and then decreased as the increase of B_2O_3 loading. The catalyst adding 0.5% B_2O_3 showed the highest activity and the conversion of CO was 55%. The characterization results indicated that the addition of B_2O_3 had influences on the structure and surface acidity of catalysts and the dispersion of active components, which further impacted the activity of catalysts. Highcrystallization and enhancement of strong acid quantity were not beneficial to the sulfur-resistant methanation, while the high dispersion of active components was favorable to the improvement of the catalyst activity.

关 键 词：催化剂 甲烷化 天然气 酸改性 氧化硼 载体 

分 类 号：TQ028.8[化学工程]