Preliminary Study On Catalysis And Acid/Basic Characters For The ZrO₂/γ-Al₂O₃ And La₂O₃/γ-Al₂O₃ Catalysts

In order to study catalytic and acid/basic characters for ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ catalysts, a MPV reaction, in which citronellal was reduced to citronellol, was selected as mode reaction. Effect of active component content on catalytic reactivity of ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ samples was studied, NH₃ and CO₂ was selected as probe molecules for IR and TPD technology. Surface area and surface acid / basic characters was measured for ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ samples by probe molecule - IR and -TPD technology. Main result as follow:1. ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ catalysts was prepared by impregnation. The active component content showed largely influence on catalytic reactivity of ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ samples. For ZrO₂/γ-Al₂O₃ samples, ZrO₂ content was 3.2～4.7 wt.%, conversion of citronellal and selectivity of citronellol is over 80%, and for La₂O₃/γ-Al₂O₃, La₂O₃ content was 10～13 wt.%, conversion of citronellal is 70～80% and selectivity of citronellol over 70% in MPV reduction of citronellal .2. In same preparation condition, influence on active component content on surface area and acid/basic characters has been observed for all catalyst samples. Surface area decreased with increase of active composition content of these samples. Basic amount increases with active composition content. Distribution of basic site was changed, conversion of citronellal increased.3. ZrO₂/γ-Al₂O₃ and La₂O₃/γ-Al₂O₃ samples can be recycled.