摘要
报道在催化剂装量３０ｍｌ的环形固定床和直管固定床两种反应器上，ＭｇＯ／ＢａＣＯ３催化剂甲烷氧化偶联反应的５００ｈ稳定性试验结果。采用甲烷和纯氧为原料气，水蒸汽为稀释剂的共进料模式。试验结果表明，ＭｇＯ／ＢａＣＯ３催化剂在５００ｈ稳定性试验中一直保持着较高的催化活性，在直管固定床反应器上，Ｃ２烃收率１６．３％，Ｃ２烃选择性６５．０％。在环形固定床反应器上，Ｃ２烃的收率１７．３％，Ｃ２烃选择性６７．０％。为了控制反应速度，水蒸汽作为稀释气引入到反应中。水蒸汽在反应中可分散和带走催化剂床层过多的反应热，减小床层温差。ＸＲＤ结果表明，反应后的催化剂与新鲜催化剂的结构基本一致，说明催化剂具有稳定的催化活性的原因，应归属于其结构的稳定性和具有一定的抗水蒸汽性能。还考察了不同甲烷空速、反应器管壁温度、水蒸汽含量对反应性能的影响。
wo types of circular and tubular thin layer fixed bed reactors were tised to facilitate the reaction heat transfer to carry out 500h stability tests on 30ml MgO/BaCO3 catalyst. The results indicated that the catalyst was very stable during the tests. In the tubular fixed-bed,with CH4: O2: H2O= 5: 1: 7. 8 and CH4 GHSV of 5000h-1,a CH4 conversion of 25%,a C2 selectivity of 65%and a C2 yield of 16. 2% were achieved. In the circular fixed-bed,with CH4: O2: H2O=5: 1: 2. 3and CH4 GHSV of 5700h-1,a CH4 conversion of 26%,a C2 selectivity of 67. 5% and a C2 yield of 17. 3% can be achieved. Pure oxygen as oxidant and water vapor as diluent facilitate the separations of the products. Water vapor is beneficial to the transfer of reaction heat and lowers the temperature difference in the catalyst bed.The XRD analysis indicates that the structure of the catalysts are almost the same before and after the reaction. The results confirm that the structure of the catalyst is very stable and the ability to resist water is superior.In addition, the effects of different reaction conditions, such as the residence time of CH4,temperature of reactor wall,water vapor content,have been investigated.
出处
《石油化工》
CAS
CSCD
北大核心
1996年第4期241-248,共8页
Petrochemical Technology
关键词
甲烷氧化偶联
稳定性
天然气
反应器
催化剂
ethane, catalyst, circular fixed-bed, water vapor, stability test
