1. In the brine-lime method, the lime milk prepared by the purification and refining treatment and the lime treated by the digested and slag-treated lime is precipitated in a sedimentation tank, and a flocculant is added to the obtained slurry, and after fully mixing, the mixture is introduced. The settling tank is separated, and then filtered, washed, dried, and pulverized to obtain a finished magnesium hydroxide.
2. The brine-ammonia method is a raw material that removes impurities such as sulfate, carbon dioxide, and a small amount of boron by purification, and uses ammonia water as a precipitant to carry out a precipitation reaction in a reaction vessel, and a certain amount of seed crystals are supplied before the reaction. Stir. The ratio of brine to ammonia is 1: (0.9 to 0.93) and the temperature is controlled at 40 °C. After the reaction is completed, a flocculating agent is added, and the precipitate is filtered, washed, dried, and pulverized to obtain a finished magnesium hydroxide.
The test method needs to improve the yield, shorten the washing cycle, and improve and perfect the production process.
3. Magnesite-hydrochloric acid-ammonia method Magnesite ore and anthracite or coke are calcined in a shaft kiln to form magnesium oxide and carbon dioxide. The bitter soil powder is adjusted to a slurry and then reacted with a predetermined concentration of hydrochloric acid to prepare a magnesium chloride solution. The magnesium chloride solution is reacted with a certain concentration of ammonia water in a reactor, and the product is washed, sedimented, separated by filtration, dried, and pulverized to obtain a magnesium hydroxide product. A surface treatment agent may be added for surface treatment as needed.
4. Microcrystalline magnesium hydroxide
A saturated solution of MgCl 2 ·6H 2 O was prepared at room temperature, and an excess amount of concentrated aqueous ammonia was introduced under stirring at 70 ° C, and magnesium hydroxide was gradually precipitated.
Note 1: The distilled water and ammonia water used should not contain CO2. The distilled water should be fully boiled. The CO2 in NH3 should be removed by KOH. Device for preparing magnesium hydroxide Note 2: The reaction vessel should be made of hard glass to avoid the reaction of Mg(OH)2 with silicic acid.
The resulting precipitate was allowed to stand in the mother liquor for two days, during which time it was allowed to warm several times, each time to 70 ° C, and then the precipitate was decanted and washed. It was then placed in a paraffin-coated nickel beaker and washed by centrifugation with distilled water containing no CO2. The precipitation and decantation operations can be carried out in the apparatus as shown in the figure, and the obtained magnesium hydroxide is first dried under vacuum on potassium hydroxide and then dried under vacuum on phosphorus pentoxide.
5. Large grain magnesium hydroxide.
243 mL of water was added to a wide-mouth platinum vessel, and 1375 g of KOH and 485 g of MgCl 2 ·6H 2 O were added, and the mixture was heated to 210 ° C on an electric furnace and clarified after about half an hour. Then, it was slowly cooled to room temperature in 18 hours, that is, crystals having a diameter of about 0.2 mL were precipitated, and dried at 100 ° C for 2 hours to obtain large-grained magnesium hydroxide.
Fengcheng City Heqi Brucite Mining Co., Ltd., is an imports and exports mining company registered in 1998 in Fengcheng City of Liaoning Province. the company is located in Fengcheng City, Primarily engaged in processing minerals. The company property mainly manufactures magnesium hydroxide flame retardant and brucite powder. The export work is handling by DALIAN HEXIN NEW MATERIAL TECHNOLOGY CO., LTD.
Our annual output amount is up to 100,000 tons. Quality,Integrity, Innovation are our business ideas. Relying on quality products, good services, our company possess good reputation in the line.
"Business Integrity, Standardize Services, Sustainable development, Dedicated to Community" is the company’s Principles. During several years developing, the company possesses own mines and processing plants,It consists of the heqi brucite mine in Fengcheng city (reserves 3,000,000 tons, annual output is 100,000 tons).