Method and device for preparing cerium-based rare earth polishing powder by virtue of spray pyrolysis

The invention relates to a method and a device for preparing cerium-based rare earth polishing powder by virtue of spray pyrolysis and belongs to the technical field of materials. The method comprises the following steps: (1) dissolving rare earth chloride and a fluorine-containing additive in water to prepare a solution; and (2) by adopting air as a carrier gas, spraying the solution into a calcining furnace for calcining and naturally cooling calcined slag generated by the calcining to obtain the cerium-based rare earth polishing powder. The device comprises the calcining furnace and a cyclone separation device, wherein the inlet formed in the bottom of the calcining furnace is connected with a blowing pipe which is communicated with a liquid inlet tank and the liquid inlet tank is communicated with the outlet of an air compressor; the cyclone separation device comprises at least two stages of cyclone separators which are connected in series, and the gas outlet of the last-stage cyclone separator is communicated with the inlet of a tail gas absorption tower. F element in the cerium-based rare earth polishing powder prepared by the method, which is disclosed by the invention, only exists in a form of CeF3 so that the preparation of the cerium-based rare earth polishing powder by direct decomposition of the mixed solution of rare earth chloride can be achieved and the raw material consumption caused by calcining ammonium bicarbonate or fluorosilicic acid precipitates is avoided.