Production method of caking-proof strontium chloride hexahydrate

Abstract

The invention relates to a production method of strontium chloride hexahydrate for liquid crystal glass base plate production. The production method comprises the following steps: a, concentrating a strontium chloride solution at the temperature of less than 100 DEG C to 38-44 baume degrees; b, cooling and crystallizing the solution, wherein the specifically steps are as follows: firstly adding crystal seeds, which are strontium chloride hexahydrate crystals with a particle diameter of less than 1 millimeter, at the charging ratio above 2 kg / m<3> and controlling cooling speed; c, ageing a crystal slurry solution reaching the temperature for 1.5-3 hours under the stirring condition; and d, putting aged crystal slurry in an automatic centrifugal machine for dehydration, and drying with cold wind so as to obtain a finished product. According to the production method provided by the invention, the surface of the strontium chloride hexahydrate crystal has extremely low adhered water and low impurities; by a stacking test for 6 months, no caking phenomenon occurs; and by a stacking test for 9 months, little caking phenomenon occurs (the ratio of caking is 5-8%), and the cakes can be loosened by lightly pinching with hands.

Description

technical field [0001] The invention relates to a production method of strontium chloride hexahydrate, especially the strontium chloride hexahydrate mainly used in the production of liquid crystal glass substrates. Background technique [0002] Since liquid crystal glass substrates have extremely high requirements on the mixing uniformity of raw materials, all formula raw materials are required to have excellent looseness, so as to facilitate the mixing of raw materials and reduce the reject rate of its products. [0003] Strontium chloride hexahydrate is one of the most important raw materials in the production of liquid crystal glass substrates. At present, the production process of strontium chloride hexahydrate is mainly: by adding organic substances containing hydrophobic groups to strontium chloride hexahydrate products, including Covering the surface of strontium chloride hexahydrate crystals, there are many similar anti-caking agents in the prior art, and this method...

AI Technical Summary

Problems solved by technology

[0004] But there are two serious defects as follows: 1, because the added additives all contain harmful components such as phenyl groups, in the production process and use, all bring pollution to the environment, and have adverse effects on human health; 2, anti-corrosion The effective time of blocking is generally 2-3 months. In the case of long-distance transportation or long-term storage of the product, the anti-caking agent will fail, and the product will still agglomerate, which is not conducive to the production and use of liquid crystal glass substrates; 3. Add chlorinated hexahydrate The anti-caking agent in strontium products will enter the liquid crystal production system, but for the liquid crystal glass substrate, the organic anti-caking agent such as the anti-caking agent is an impurity, and the introduction of these impurities will inevitably have a negative impact on the quality of the liquid crystal glass substrate