SULFURIC ACID PROCESSING OF KAOLIN ANGRENA DEPOSIT

Abstract

The article studies the processes of sulfuric acid processing of kaolin from the Angren deposit. In order to develop a technology for producing a coagulant - aluminum sulfate from kaolin, the decomposition of aluminosilicate clay pre-moistened with concentrated sulfuric acid was studied, and a process flow chart for obtaining the product was developed. For the study, kaolin from the Angren deposit was used with the following composition (mass.%): Al2O3=21,73, Fe2O3=1,68, SiO2=65,2, TiO2=0,4, СаО=0,4, MgO=0,65, R2O=0,8, SO3=0,6, п.п.п.= 8,5 Kaolin was calcined at a temperature of 400 °C to 800 °C for 60-120 minutes, determining weight loss. The cake was decomposed with 60% sulfuric acid for 60 minutes at a temperature of 80 °C and a sulfuric acid rate of 100% of the stoichiometry for binding Al2O3 to Al2(SO4)3. The maximum degree of aluminum extraction is noted at a sulfuric acid concentration of 60%. In this case, the degree of aluminum extraction is 97.1%, and iron 82.5%. The conducted studies on the decomposition of calcined kaolin at a temperature of 650-700 °C for 1 hour showed the possibility of obtaining an aluminum sulfate solution with an extraction rate during leaching of at least 96.0%. The optimal technological parameters for extracting aluminum from kaolin with sulfuric acid are an acid concentration of 60%, a rate of 100%, a temperature of at least 80 °C, and a process duration of at least 1 hour