MUMBAI, India, Nov. 14 -- Intellectual Property India has published a patent application (202517096694 A) filed by Universite Mohammed VI Polytechnique, Ben Guerir, Morocco, on Oct. 7, for 'method for recovering rare earths and coproducts from phosphogypsum and phosphoric acid sludge.'
Inventor(s) include Khaless, Khaoula; Chanouri, Hamza; and Benhida, Rachid.
The application for the patent was published on Nov. 14, under issue no. 46/2025.
According to the abstract released by the Intellectual Property India: "The present disclosure relates to a method for treating phosphogypsum or phosphoric acid sludge in order to recover rare earths, the method comprising the following consecutive steps: (a) treating the phosphogypsum or the phosphoric acid sludge according to the following steps (a1) or (a2), respectively: (a1) washing the phosphogypsum with a polar solvent and collecting the obtained solid residue; or (a2) separating the phosphoric acid sludge into a liquid phase and a solid residue, and separately collecting the obtained solid residue and the obtained liquid phase; washing the solid residue obtained at the end of the treatment step with a polar solvent at room temperature and separately collecting the obtained solid residue and the obtained liquid phase; and washing the solid residue obtained at the end of the washing step with a hot polar solvent and collecting the obtained solid residue and the obtained liquid phase; (b) drying, grinding and sieving the solid residue obtained at the end of step (a); (c) alkaline leaching the solid residue obtained at the end of step (b) using a strong inorganic base, and collecting the obtained solid residue and the obtained liquid phase; (d) drying, grinding and sieving the solid residue obtained at the end of step (c); (e) acid leaching the solid residue obtained at the end of step (d) using nitric acid and collecting the obtained solid residue and the obtained liquid phase; (f) precipitating calcium nitrate crystals from the liquid phase obtained at the end of step (e) and collecting the solid residue and the obtained liquid phase; (g) adjusting the pH of the liquid phase obtained at the end of step (f) to a value of between 1 to 1.8 by adding a strong base and collecting the obtained solid residue and the obtained liquid phase; (h) drying the solid residue obtained at the end of step (g) to obtain a solid product containing rare earths."
The patent application was internationally filed on Mar. 15, 2024, under International application No.PCT/MA2024/050009.
Disclaimer: Curated by HT Syndication.
