What are the main processes for preparing magnesium carbonate?

Raw material preparation:using brine,seawater and other solutions containing magnesium chloride and magnesium sulfate as raw materials.

 

The preparation process of magnesium carbonate mainly depends on different raw material routes.The following are several common preparation methods:

Brine carbonation method

Raw material preparation:using brine,seawater and other solutions containing magnesium chloride and magnesium sulfate as raw materials.

Chemical reaction:It involves digestion,precipitation,carbonization,pyrolysis,and other reactions with carbon dioxide produced after calcination of dolomite or limestone to produce light magnesium carbonate.

Magnesite carbonization method

Raw material preparation:Mix magnesite ore with a particle size of 100-300mm and white coal in a certain proportion.

Calcination treatment:Calcination is carried out in a vertical kiln,controlling the temperature at different stages to generate magnesium oxide and carbon dioxide.

Digestion and absorption:Light burned bitter soil is crushed and reacted with hot water for digestion and absorption to produce magnesium hydroxide.

Carbonation reaction:Magnesium hydroxide undergoes carbonation reaction with purified carbon dioxide in the carbonation tower to produce magnesium bicarbonate.

Subsequent processing:After sedimentation,separation,pyrolysis,filtration,and drying,light magnesium carbonate is produced.

Bitter soil decomposition method

Raw material preparation:Use magnesium sulfate solution generated by the reaction of bitter soil powder and dilute sulfuric acid.

Chemical reaction:Magnesium sulfate solution reacts with ammonium bicarbonate,and the crystallization rate is generally above 70%.

Preparation method of high-purity magnesium carbonate

Dissolve magnesium nitrate:dissolve magnesium nitrate in boiling water,adjust the specific gravity of the solution,and then cool it to separate and crystallize.

Add ammonium carbonate:Dissolve the crystals in water again and add ammonium carbonate solution until a white precipitate is formed.

Adjust the PH value:slowly add the second filtrate to the first filtrate under stirring,adjust the PH=8,stand still,separate and precipitate.

Washing and drying:Wash the precipitate multiple times with hot water until pH=7,centrifuge,and dry to obtain high-purity magnesium carbonate.

In summary,there are various preparation processes for magnesium carbonate,and suitable methods should be selected according to different raw materials and requirements.These processes not only reflect the complexity and diversity of the chemical industry,but also provide a solid foundation for the widespread application of magnesium carbonate.Through continuous technological innovation and optimization,the production and application prospects of magnesium carbonate will become even broader.