Separation of cerium and non-cerium rare earth, method of manufacturing cerium based relief polishing powder

Abstract

The invention relates to a technique for separating cerium and non-cerium rare earth from mixed rare earth and producing a by-product of cerium-based polishing powder. The invention adopts a high temperature fluorating method to add fluorin into the cerium-bearing mixed rare earth, 1 wt percent to 50 wt percent of CeO2 is added in the fluorin, and the mixed rare earth is fluorated for 0.5 to 8hr under the high temperature of 200 DWG C to 800 DWG C, the fluorin is firstly reacted with cerium to form a cerium fluorin compound which is indissolvable in acid, the cerium fluorin compound is dissolved by adding acid, after the dissolution, the non cerium rare earth soluble in acid is dissolved in the solution, and the fluorin is left in the slag, therefore the purpose of separating fluorin from non fluorin can be easily realized. The early dissolved slag comprises cerium and the fluorin, which are identical with the major components of cerium-based polishing powder, and particles with equalized sizes can be obtained after washing and ignition, sizes ranging from D50 to 2 to 5 microns comply with the standard of the polishing powder application. The invention has the advantages that the whole process reduces the solid-iquid separation step, the auxiliary material consumption is reduced, the production of equipment per unit is improved, the recovery rate of the rare earth is increased, and the pollution in the producing process is minor, F-bearing waste water discharging does not exist, in addition, the early dissolved slag product with low value is manufactured into polishing powder with high added value, so the production efficiency is greatly improved.

Description

technical field [0001] The invention belongs to the technical field of rare earth hydrometallurgy, and specifically relates to a technology for separating cerium and non-cerium rare earths from mixed rare earths and producing cerium-based polishing powder by-product. Background technique [0002] Since cerium can be oxidized to a tetravalent state, and the properties of cerium (IV) and other non-cerium rare earths are very different, various chemical methods are often used in the separation of rare earths to first oxidize cerium to cerium (IV) and then combine with non-cerium rare earths. Rare earth pre-separation. Common methods such as the electrolysis method mentioned in CN 86101332B, the hydrogen peroxide oxidation in CN 1119424C, the ozone method oxidation in CN 1021579C and CN 1047110A, the potassium permanganate method in CN 1028769C, the oxidation roasting method in CN 1683569A, etc., Both oxidize cerium (III) to cerium (IV) with various oxidizing agents first, and ...

AI Technical Summary

Problems solved by technology

However, this method is more strict on acid control, and this method has no obvious effect on mixed rare earth carbonates and mixed rare earth oxides.

[0009] Most of the above processes are based on monazite ore and mixed concentrate treatment methods, so there are some problems to varying degrees, such as: complex process, high cost, serious environmental pollution, etc.