Conversion of Phosphogypsum Based on Products of Oxidation of Vegetable Residues by Hydrogen Peroxide in the Presence of Sulfuric Acid

The results of studying the processes of oxidation of vegetable residues (VR) by hydrogen peroxide in the presence of sulfuric acid depending on the oxidant rate, temperature, duration and mass ratio are presented. The results of the study of phosphogypsum conversion processes by neutralization with 25 % ammonia water to pH = 7.5 in the presence of oxidized VR at ratios phosphogypsum : VR = 1 : (0.2–2) are presented. The preferable ratio of phosphogypsum : VR = 1 : 1.5 with ammonization of the mixture to pH = 7, resulting in a relative content of the aqueous form of SO 3 is 71.10 %. The optimum process parameters were determined, the basic process scheme was developed and the material balance of VR oxidation and phosphogypsum conversion was calculated.