Adding potassium nitrate in precipitated barium sulfate will increase the solubility. This is due to the strong electrolyte—KNO3 which makes the ions of solvent increased. Ions with different charge attract each other, which reduces Ba2+ and SO42-activities and makes the equilibrium of BaSO4==Ba2+ + SO42- shifted toward the right side. Then increase the solubility until reaching a new equilibrium. This effect caused by adding electrolyte with different ions to increase solubility is called “salt effect”.

     The technical process of barium sulfate made from salt slurry:

     1 Pulping—Add water in salt slurry, mix them with a scale of 1:3-5 and heat to 70-100℃ by steam.

     2 Dissolution—Add 4 times to 6 times solvent A in salt slurry, blend them 50 to 70 minutes, keep the material temperature at 50-70℃ and repeat the operations.

     3 Reaction—Add solvent B with a concentration of 1-5% in the feed liquid. The addition is 3 to 6 times of material liquid. Mix and keep the material liquid temperature at 50-70 degrees and repeate the operations;

    4 Separation—Filter and wash the above material liquid with water. Repeat washing until the liquid conductivity is 100 us/cm without chloride ion (Cl).

   Main product features: Domestic advanced chemical precipitation process is adopted to produce barium sulfate. It is amorphous white powder or paste with superior physical performance, less mechanical impurities and uniform fineness. Besides, it is nontoxic, insoluble in water, soluble in fuming sulfuric acid, slightly soluble in boiling hydrochloric acid with stable chemical properties and other features.

     Scope of application: It can absorb X-ray, gamma-ray and give material high density and surface smoothness. Therefore, it is widely used in paint, ink, coating, plastic, rubber, chip, friction plate, ceramic, glass, electronic, cosmetic, medicine, food and other fields.