采用分步浸渍法制备了一系列Ru1-La-O/γ-Al2O3复合氧化物催化剂,在固定床微反装置中进行CO选择性氧化催化性能研究。考察了催化剂上不同La2O3添加量、不同再生方法对催化剂CO选择性氧化反应性能的影响,并通过TPR、XRD等手段对催化剂进行了表征。结果表明,添加w(La)=10%的Ru1-La-O/γ-Al2O3催化剂在110℃~170℃温度区间具有99%以上的CO转化率,并且催化剂的选择性相对较高。经氮气、氢气及氧气再生处理后的Ru1-La-O/γ-Al2O3催化剂,其催化活性有所不同,其中经氧气处理后的催化剂,表面吸附氧含量较高,活性恢复较好。
Ru-La-O/γ-Al2O3 composite oxide catalysts with various La2O3 contents were prepared by two-step impregnation method, and the selective oxidation of CO in the hydrogen-rich gas over the prepared catalysts was studied in a fixedbed micro-reactor. The catalysts were characterized by means of TPR and XRD, and the effect of La2O3 loading and regeneration methods on the activity of catalysts were investigated. The results showed that high CO conversion (〉99%) and selectivity could be obtained in a wide temperature range of 110℃-170℃ over the catalysts with appropriate quantity of La2O3. The optimum catalyst was Ru1-La-O1/γ-Al2O3 with La mass fraction of 10%, and the deactivated catalyst could be regenerated to some extent by treating at 250℃ in nitrogen or 20% H2/N2 atmosphere, while it could be well regenerated in 20% O2/N2 at the same temperature, which was probably due to that the treatment in 20% O3/N2 atmosphere could increase the surface absorbed oxygen.