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采用柠檬酸络合低温浸渍法制备分子筛负载钙钛矿型复合氧化物催化剂。采用XRD、SEM和H2-TPR等手段对催化剂性能进行表征,并在微型固定床反应器中对催化剂进行活性评价。结果表明,在钙钛矿型复合氧化物中进行B位离子掺杂,可以改善催化活性,碳颗粒燃烧温度降低。在20%LaCoO3/HZSM-5催化剂中用铁离子部分取代钴离子可以改善碳颗粒的燃烧性能,取代量增加碳颗粒燃烧温度降低,但是生成CO2的选择性也降低,以20%LaCo0.2Fe0.8O3/HZSM-5为催化剂,Tig、Tm和Tf分别为256℃、399℃和403℃,但生成CO2的选择性只有72.5%。在20%LaCo1-xFexO3/HZSM-5中的钙钛矿型复合氧化物B位离子中加入铜离子后,在碳颗粒燃烧反应中生成CO2的选择性得到明显改善,Sco2提高10个单位以上。以20%LaCo0.2Fe0.6Cu0.2O3/HZSM-5为催化剂,在碳颗粒燃烧反应中生成CO2的选择性可以达到94.7%,Tig、Tm和Tf分别为242℃、427℃和445℃。
Preparation of molecular sieve supported perovskite-type composite oxide catalyst by citric acid complexed low temperature impregnation method. The catalyst performance was characterized by XRD, SEM and H2-TPR, and the activity of the catalyst was evaluated in a miniature fixed bed reactor. The results show that B-ion doping in perovskite-type composite oxide can improve the catalytic activity and decrease the combustion temperature of carbon particles. Partial substitution of cobalt ions with iron ions in 20% LaCoO3 / HZSM-5 catalyst can improve the combustion performance of carbon particles. The substitution amount increases the burning temperature of carbon particles, but the selectivity of CO2 generation decreases with 20% LaCo0.2Fe0. 8O3 / HZSM-5 as catalyst, Tig, Tm and Tf were 256 ℃, 399 ℃ and 403 ℃ respectively, but the selectivity of CO2 generation was only 72.5%. The addition of copper ions to the B-site of perovskite-type complex oxide in 20% LaCo1-xFexO3 / HZSM-5 significantly improved the selectivity of CO2 generation in the combustion of carbon particles, increasing Sco2 by more than 10 units. With 20% LaCo0.2Fe0.6Cu0.2O3 / HZSM-5 as catalyst, the selectivity of CO2 generation in the combustion of carbon particles can reach 94.7% with Tig, Tm and Tf of 242 ℃, 427 ℃ and 445 ℃, respectively.