Patent ID: 9586835
Date: 2017-03-07
CPC Classifications: C01C,C01F,C01P,C22B

Claim:
1. A method of producing a magnesium sulfate and hydrated ammonium double salt, with the formula MgSO4.(NH4)2SO4.XH20 (Boussingaultite), comprising: a) providing a synthetic solution of magnesium sulfate or a liquid effluent comprising magnesium sulfate; b) adding sulfuric acid to the solution of step a) until the pH is in the range from 3.0 to 4.0 to form a reaction medium; c) adding ammonium hydroxide or ammonia to the reaction medium of step b) until the pH is in the range from 4.0 to 6.0; d) sequentially repeating steps b) and c) until the consumption of stoichiometric amounts of the reactants for the formation of Boussingaultite solid; e) crystallizing the Boussinqaultite solid by the evaporation of water from the reaction medium by heating at a temperature of 80±5° C., and filtering.