摘要
采用共沉淀法制备了一系列ＭｎＯｘ／γＡｌ２Ｏ３催化剂，并利用连续流动反应装置考察了它们对苯甲酸加氢制苯甲醛反应的催化性能．结果表明，催化剂对本反应有理想的反应活性和选择性；催化剂Ｍｎ载量为１０％～２０％及反应温度为６９３Ｋ时，苯甲酸转化率为９９％，苯甲醛选择性为９６％．ＢＥＴ比表面积测定结果反映了焙烧温度和活性组分载量对催化剂比表面积的影响．ＸＲＤ结果揭示了催化剂还原前后的物相分别为Ｍｎ２Ｏ３和ＭｎＯ，并用热分析方法确定了Ｍｎ２Ｏ３于载体γＡｌ２Ｏ３表面的单层分散阈值．
The catalysts MnO x/γ Al 2O 3 were prepared by means of co precipitation method. The catalytic performance of Mn 2O 3/ γ Al 2O 3 catalyst for vapour phase hydrogenation of benzoic acid to benzaldehyde was investigated in a continuous flow and fixed bed reactor. The results showed that the Mn 2O 3/ γ Al 2O 3 catalyst had better activity and selectivity for the reaction. When Mn loading is 10%～20% and reaction temperature is 693 K, the conversion of benzoic acid is more than 98% and the selectivity for benzaldehyde is more than 96% . At the same time, the effects of calcination temperature and Mn loading on the surface area of catalysts were examined by BET technique. The surface composition of catalysts before and after reaction was disclosed by XRD technique, and the monolayer dispersion capacity of Mn 2O 3 on γ Al 2O 3 surface so called threshold value of dispersion was determined by TA technique.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
1997年第5期384-387,共4页
关键词
苯甲酸
氧化锰
锰
负载型催化剂
加氢
苯甲醛
Benzoic acid, Manganese oxide, Alumina, Supported catalyst, Catalytic hydrogenation, Benzaldehyde, Dispersion threshold
