A Series Of Perovskite LaMnO₃ Catalyst Were Synthesized By DL-Alanine Solution Combustion

In the Paper, a series of perovskite LaMnO3 catalysts with the large surface area were successfully prepared by alanine solution combustion methods; The effects of calcination temperature(t), stoichiometric ratio of organic fuel to oxidizer ((?)), A-sites doped metal (Sr), B-sites doped transition metal (Ni) and the organic fuel,for LaMnO3 catalysts and the catalytic activity for CO combustion were studied. The synthesized samples were characterized by means of XRD,BET and SEM methods.1. The LaMnO3 catalysts were synthesized by DL-alanine solution combustion method. We find that,(?)= 1.5 and the calcination temperature t=600℃are the best technological parameters.2. The LaMnO3 catalysts of A-sites doped metal (Sr) were synthesized by alanine solution combustion method. We find that, the surface area of La1-xSrxMnO3 mixed oxides are all increased, as A-sites doped metal (Sr); with the(x) value's bigger and bigger, the surface area of La1-xSrxMnO3 enlarged firstly and then decreased; and the catalytic activity for CO combustion enhanced firstly and then decreased. When the (x) value is equal to 0.2, the surface area of La0.8Sr0.2MnO3 is the largest and the catalytic activity is the best of the series of La1-xSrxMnO3 catalysts.3. The LaMnO3 catalysts of B-sites doped metal (Ni) were synthesized by alanine solution combustion method. We find that, the surface area of La0.8Sr0.2Mn1-yNiyO3(y=0-0.3) are all decreased, as B-sites doped metc(Ni); but approached the surface area of La0.8Sr0.2MnO3. With the (y) value's bigger and bigger, the catalytic activities for carbonic oxide combustion decreased regurally. When the(y)value is equal to 0.4, the surface area of La0.8Sr0.2Mn0.6Ni0.4O3 is the largest and the catalytic activity is the best of the series of La0.8Sr0.2Mn1-yNiyO3 catalysts. The sequences of activities are: La0.8Sr0.2Mn0.8Ni0.2O3