Selective Oxidation Of Propane To Acrylic Acid

Acrylic acid and its esters are important industrial materials widely used inmany fields, such as the produce of dope, textile, and petrochemicals. There are twosteps to get them in industry: (1) The oxidative dehydrogenation of propane topropene, (2) The selective oxidation of propene to acrylic acid. Preparing acrylic acidwith propane is one of the hottest topics because of high costs of equipments andenergy waste.Many methods were used to prepare catalysts. It is found that the sol-gelmethod can be used to prepare muti-metals oxide catalysts. The catalysts prepared bysol-gel method will own much specific surface and higher separation of active matter,comparing to catalysts prepared by other methods, such as coprecipitating method,complexing method, dipping method, etc. The catalytic performance proves thatbetter activity and selectivity of acrylic acid can been obtained when catalyst isprepared by sol-gel method. Especially, more than 85% is aim product among allliquid products.A good catalyst Ag_yBi_1-x-yV_1-3xMo_3xO₄Ф_x/γ-Al₂O₃(X=0.23, Y=0.01)wasprepared by sol-gel method, Considering the effects of supports and other factors,and conversion of propane 20.2% and selectivity of acrylic acid 8.7% were obtained.For catalysts with scheelite structure, Ag⁺ contributes to oxygenation of intermediateproduct, Bi³⁺ to transmission of O^2- and absorption of O₂, V⁵⁺ to reaction ofpropane to propene, and Фx can prove a active position for selective oxidation.The supported inorganic membrane was prepared with different method. A neatand nice membrane was prepared, when the support membrane was dipped with themixture of active phase powder and sol.