【摘要】 用EDTA 柠檬酸联合络合法合成了新型混合导体透氧膜材料 ,成功地制备了致密膜片并对其透氧性能进行了考察 .结果发现 ,此新材料具有非常大的透氧能力 ,850℃时在膜一端为干燥的流动空气而另一端为流动的氦气下 ,透氧量高达 0 744μmol/(cm2 ·s) .考察了膜片本身对甲烷的活化性能 ,发现导体膜对甲烷氧化偶联具有催化活性 ,随着甲烷流速的增加 ,甲烷转化率降低 ,而C2 选择性升高 .研究了膜反应器中甲烷部分氧化制合成气反应 ,甲烷转化率约为 90 % ,CO选择性约为 98% ,CO/H2 比约为 2 ;同时 ,膜的透氧量急剧增加到约 6 0 1 μmol/(cm2 ·s) ,这归结于膜反应侧氧分压的急剧降低 .更多还原

【Abstract】 A novel mixed conducting oxygen permeable membrane material, Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3- δ , was synthesized using combined EDTA citrate complexing method. The dense membrane made of such material was successfully fabricated, and its oxygen permeation was studied. The membrane had very high oxygen semipermeability, at 850 ℃ and under air/He with oxygen partial pressure gradient, a permeation flux of 0 744 μmol/(cm 2·s) was obtained. The intrinsic catalytic activity of the membrane for CH 4 oxidation was investigated. It was found that the membrane had higher catalytic activity for OCM to C 2, and C 2 selectivity increased but CH 4 conversion decreased with the increase of methane. For POM to syngas, CH 4 conversion was around 90%, CO selectivity was about 98% and V (CO)/ V (H 2) was around 2. Under POM reaction condition, an oxygen permeation flux as high as 6 01 μmol/(cm 2·s) was obtained owing to the increase in oxygen gradient across the membrane.更多还原