Abstract: The objective of the invention is the development of a new process for producing sulfur from phosphogypsum. During this process, the phosphogypsum is mixed with a source of carbon and hydrogen forming a slurry after mixing. This source of carbon and hydrogen is a natural or synthetic organic polymer, as an example that is not limiting, biomass, used tires or plastic, kerogen or tars. The granules undergo a heat treatment (100 to 150° C.) to evaporate the mixing water. The product obtained undergoes a heat treatment (550 to 900° C.) under a neutral atmosphere and/or partially oxidizing. The generated gases are bubbled in deionized water, sodium hypochlorite solution or a basic aqueous solution which allows the trapping, among others, of organosulfur molecules and the precipitation of sulfur S8. Non-entrapped gases are recovered to extract volatile sulfur products.

Abstract: The present disclosure relates to a method for producing zinc phosphate with the application of ultrasound having a frequency greater than 100 KHZ.

Abstract: The invention relates to a method for manufacturing ammonium sulphate and calcium carbonate from phosphogypsum, characterised in that it comprises the following steps: —dispersing phosphogypsum in water to form a phosphogypsum liquid suspension, —sparging gaseous carbon dioxide and gaseous ammonia in the phosphogypsum liquid suspension to precipitate calcium carbonate, —filtering the phosphogypsum liquid suspension to produce a filtrate comprising ammonium sulphate, and a solid residue comprising the calcium carbonate precipitate, —evaporating the filtrate to produce ammonium sulphate and drying the solid residue to produce calcium carbonate.