| 摘要 |
A process for recovering phosphoric acid from phospho gypsum produced as a by-product in a conventional phosphoric acid production plant and having water soluble P2O5 bound in the crystal lattice thereof is provided. The process comprises forming a suspension of phospho gypsum in an aqueous medium, subjecting the suspension to ultrasonic waves under conditions suitable to shatter the phospho gypsum crystal lattice releasing the bound water soluble P2O5 into the aqueous medium, and recovering the phosphoric acid so released. The depleted phospho gypsum is preferably treated in a further step to reduce any remaining water soluble P2O5 to a level which allows the gypsum to be added to a cementitious material for use as a setting regulator. |
