A kind of preparation technology of cerium-based polishing powder

Abstract

The invention provides a preparation method of a cerium-based polishing powder. The preparation method comprises following steps: (1) an aqueous solution of magnesium bicarbonate and / or an aqueous solution of calcium bicarbonate is taken as a precipitating agent, and the precipitating agent and a salt solution containing cerium ions are mixed uniformly so as to obtain a slurry; (2) the slurry obtained via steps (1) is subjected to heat preservation aging for 0.5 to 48h at a temperature of 30 to 90 DEG C, and then is filtered and dried so as to obtain precursor powder of the cerium-based polishing powder; (3) the precursor powder is subjected to calcination at a temperature of 600 to 1100 DEG C, obtained powder is subjected to postprocessing of dispersing and sorting so as to obtain the cerium-based polishing powder. The preparation method is capable of improving properties of the cerium-based polishing powder, reducing production cost of the cerium-based polishing powder, and avoiding environmental pollution caused by ammonia-nitrogen wastewater.

Description

technical field [0001] The invention relates to a preparation process of cerium-based polishing powder, which belongs to the field of preparation of rare earth materials. Background technique [0002] The history of the development of rare earth polishing powder can be traced back to the First World War. The United States and Canada took the lead in using rare earth polishing powder with cerium oxide as the main component. Compared with traditional polishing powder, rare earth polishing powder has the advantages of fast polishing speed, high finish and long service life, and can improve polishing quality and operating environment. Rare earth polishing powder has become the first choice for glass polishing materials because of its high polishing efficiency brought about by its unique chemical-mechanical action principle. It is widely used in lenses, optical components (lenses, prisms), color TV glass shells, electronic glass for flat panel displays, Polishing of silicon wafe...

AI Technical Summary

Problems solved by technology

Although the current CeO 2 There are many reports on the preparation of CeO, but there are generally problems such as serious particle agglomeration and unstable performance, which affect the quality of CeO. 2 Abrasive performance

[0004] The preparation method of polishing powder at home and abroad generally adopts oxalic acid or ammonium bicarbonate precipitation, but oxalic acid is expensive, the production cost is high, and a large amount of oxalic acid wastewater is produced

However, ammonium bicarbonate is used as a precipitant to prepare polishing powder. The ammonium ions entrained in the precipitation process will form defects in the crystal lattice of the polishing powder during roasting, resulting in crystal deformation and performance degradation.

In addition, a large amount of ammonia nitrogen wastewater will be produced to pollute the environment. The cost of recycling and processing ammonia nitrogen wastewater is very high, and it is difficult to meet the requirements of environmental protection standards.

In order to eliminate ammonia nitrogen wastewater pollution, some enterprises use sodium carbonate or sodium hydroxide instead of ammonium bicarbonate and ammonium hydroxide as precipitants to produce metal carbonates, hydroxides or metal oxides, but the cost is doubled, and it also brings Sodium salt wastewater pollution