M-Mn-W/SiO_2/堇青石整体式催化剂及其甲烷氧化偶联反应性能  

Preparation of M-W-Mn/SiO_2/cordierite monolithic catalysts and their performances for oxidative coupling of methane

作　　者：唐晶晶[1] 季生福[1] 王开[1] 李成岳[1] 

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室,北京100029

出　　处：《天然气化工—C1化学与化工》2009年第3期19-23,26,共6页Natural Gas Chemical Industry

基　　金：国家重点基础研究规划(973)项目(批准号:2005CB221405)资助

摘　　要：以Na2WO4、Mn、M(M=Ce,Bi,Sr,La)为活性组分,采用浸渍法制备了一系列M-W-Mn/SiO2/堇青石整体式催化剂。在微型固定床反应器中对催化剂的甲烷氧化偶联反应性能进行了评价。采用XRD和TPR对催化剂的结构进行了表征。考察了反应条件对催化性能的影响。催化活性评价结果表明,在较大的空速下,M-W-Mn/SiO2/堇青石整体式催化剂具有较好的甲烷氧化偶联反应性能,其中活性最好的4%Ce-5%Na2WO4-2%Mn/SiO2/堇青石整体式催化剂,在甲烷转化率为32.9%时,甲烷转化率和C2烃选择性之和可达82.9%。XRD结果显示,M-W-Mn/SiO2/堇青石整体式催化剂除了堇青石的特征峰以外,存在α-方石英、Na2WO4、Mn2O3以及一些氧化物的物相。TPR结果显示,催化剂的各活性组分之间存在一定的相互作用,从而对催化剂的甲烷氧化偶联催化反应的性能有不同的影响。A series of M-W-Mn/SiO2/eordierite monolithic catalysts were prepared by impregnation method, with cordierite ceramics as supports and Na2WO4, Mn and M （M=Ce, Bi, Sr, La） as active components, and their catalytic activity for methane oxidative coupling reaction was evaluated in a conventional quartz fixed-bed flow microreactor. The catalysts were characterized by XRD and TPR, and the effects of reactive conditions on the catalytic activity were investigated. The results showed that Ce-Na2WO4-Mn/SiO2/ cordierite monolithic catalysts had excellent properties for oxidative coupling of methane under high feed space velocity, and the summation of methane conversion and C2 selectivity of 82.9% could be obtained with a methane conversion of 32.9% over the optimal catalyst 4%Ce-5%Na2WO4-2%Mn/SiO2/cordierite. XRD results showed that the M-W-Mn/SiOdcordierite monolithic catalysts conrained α-eristobalite, Na2WO4, Mn2O3 and some other oxides. TPR results showed that there were interactions between the active components, which brought different influences to the catalytic properties.

关 键 词：M—Mn—W/SiO2 堇青石 整体式催化剂 甲烷氧化偶联 

分 类 号：O643[理学—物理化学]