添加组分对Mo-Te-Ni催化性能的影响

Effect of the additives on the performance of Mo-Te-Ni ternary mixed oxied catalysts

采用微型反应———色谱联用装置评价了Mo Te Ni催化剂添加不同金属氧化物对异丁烯选择氧化生成甲基丙烯醛反应的催化性能的影响。添加Fe、Cu、Ce氧化物可促进催化剂自身的氧化还原循环,提高氧化活性,降低反应温度;添加适宜的碱金属氧化物调节催化剂的表面酸度可显著提高MAL的选择性;添加稀土Ce氧化物还改善了催化剂的表面结构可显著提高催化剂的热稳定性。利用XRD、PM、SEM、EDAX和比表面测定对催化剂进行了表征。

Catalytic activity and selecti632)vity of a variety of Mo-Te based multicomponent mixed oxide catalysts for selective oxidation of isobutylene to methacrolein were determined by a microreactor connected in series with a gas chromatograph. The effects of each main components of catalysts were studied. Addition of Fe,Cu,Ce metal′s oxides to promote the redox cycle of catalysts themselves,which increases oxidation activity and lowers reaction temperature;appropriate amounts of alkali metal′s oxides incorporated to modify surface acidity of the catalysts and increases markedly selectivity of MAL;promoting CeO_2 content in catalysts improves the surface condition (structure) of catalysts yet and increases markedly the thermostability of Mo-Te based mixed oxide catalysts. The catalysts were characterized by XRD,PM,SEM,EDAX and surface area determination .