Research on Dihydrate Calcium Sulphate Crystallization during the Production of Phosphoric Acid by Wet Process

Huirong Du^1,2, Anyin Chen^1,2*, Li Yang¹

¹Department of Chemistry and Chemical Engineering, Sichuan University of Arts and Science, Dazhou, China.
²Key Laboratory of Exploitation and Study of Distinctive Plants in Education Department of Sichuan Province, Sichuan University of Arts and Science, Dazhou, China.

DOI: 10.4236/msce.2014.212002                

Abstract

Simulate the production of phosphoric acid by wet process is conducted in batch experiments facilities by adopting phosphorus concentrate as raw material from Wengfu, Dazhou city, with a view to study sulfuric acid concentration, reaction time, crystallization temperature of calcium sulfate, active additive, the influence of seed crystal on the size and shape of calcium sulfate crystal under conditions of Wet process phosphoric acid productive process. The research results show that under the conditions of the liquid-solid ratio of 4:1, the sulfate acid stoichiometric ratio of 1.1, phosphoric acid mass fraction of 21%, the crystallization temperature of 75°C, crystallization time of 120 min, when (NH₄)₂SO₄ taken as active additives, Mg-doped calcium sulphate crystal as crystal seed can obtain rodlike crystallization of stability, thickness, uniformity.

Keywords

Calcium Sulfate, Active Additives, Crystal Seed, Crystallization

Conflicts of Interest

The authors declare no conflicts of interest.

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