Method for removing impurity of mother liquid in preparation process of calcium carbonate crystal whisker

Abstract

The invention relates to a method for removing impurity of mother liquid in a preparation process of calcium carbonate crystal whisker, comprising the following steps of: (1) adding a barium chloride solid into the mother liquid in the preparation process of calcium carbonate crystal whisker; stirring the mixture to react for 0.5-2h at the normal temperature; and filtering in vacuum to obtain themother liquid subjected to the removal of sulfate radical; (2) adding a calcium removing agent in the mother liquid subjected to the removal of the sulfate radical; introducing CO2, stirring the mixture to react until a pH value of the mother liquid is 7; stopping aeration, and filtering in vacuum to obtain the mother liquid subjected to the removal of calcium; and (3) adding a flocculating agentwith mass concentration of 5 thousandth; stirring, standing and precipitating the mixture; and filtering in vacuum to remove the impurity. The invention has the advantages of simple operation and high impurity removal efficiency.

Description

technical field

[0001] The invention relates to the technical field of inorganic salt materials, in particular to a method for removing impurities from mother liquor in a calcium carbonate whisker production process. Background technique

[0002] At present, the methods for preparing calcium carbonate whiskers are mainly soluble calcium salt and carbonate preparation method, urea hydrolysis method, heating hydrolysis method with calcium bicarbonate, Ca(OH) 2 -CO 2 Gas-liquid reaction synthesis method, etc. Magnesium chloride is used as the crystal form control agent, and the calcium carbonate whiskers prepared by the carbonization method generally use quicklime as the raw material, bischofite as the crystal form control agent, and the calcium carbonate whiskers are prepared by the carbonation reaction of carbon dioxide. In this process, the main component of the mother liquor after whisker slurry filtration is magnesium chloride, in the follow-up preparation process of cal...