An Innovative Method for Egyptian Monazite Mineral Digestion by Sulfuric Acid

The present work deals with a study of an innovative method for Egyptian monazite mineral digestion by 98 %sulfuric acid in hydrothermal autoclaves, where the digtion of monazite take place. The aim of this work is to obtain the optimal condition of monazite digestion using sulfuric acid so that all elements contained in the monazite that are U, Th, RE, PO4 dissolved as much as possible. The parameters are sulfuric acid consumption (weight ratio of monazite ore: sulfuric acid), digestion temperature and digestion time. The results showed that the optimal conditions of digestion are 1: 1.6 of weight ratio of monazite ore: sulfuric acid, 170°C of digestion temperature, 8 hours of digestion time with 78.6 % recovery on 85 %monazite mineral purity without pre-treatment or grinding for the mineral (most pronounced advantages of the acid process) which equal to 92.5 % of pure monazite mineral. Such findings were also supported by X-ray diffraction and scanning electron microscopy analyses.