The catalytic oxidation of propylene: IV. Preparation and characterization of α-bismuth molybdate

Abstract

A coprecipitation method is described which results in the preparation of the α-phass bismuth molybdate catalyst in high purity and which is reproducible. This preparation is based on the known principles of isopolymolybdate and molybdate heteropoly chemistry. The existence of a bismuth-molybdate heteropoly precursor having a stoichiometric ratio of bismuth to molybdenum of 2 to 3 is postulated using both the solution chemistry of the molybdates as well as X-ray diffraction measurements on several air-dried and oven-dried samples of precipitates obtained from the coprecipitation procedure.