Possibility of Processing the Kaolin Clays from the Suvorovskoe Deposit with Coagulant Extraction

Abstract

The mineral and chemical compositions of the kaolin clay from the Suvorovskoe deposit are studied by X-ray diffraction and inductively coupled plasma atomic emission spectrometry. The conditions of the thermal calcination and decomposition of the kaolin clay with sulfuric and hydrochloric acids are optimized: the calcination temperature and time are 650–700°C and 60–90 min, respectively. The degree of extraction of Al₂O₃ from the calcined clay to sulfuric acid solutions is 92–94%, and that to hydrochloric acid solutions is 76–78%. The influence of different flocculants on the separation of liquid and solid phases is studied. The use of polyacrylamide is shown to increase the filtration rate by a factor of 1.5–2. The coagulation properties of aluminum sulfate and hydroxochlorides, namely, oxidizability, chromaticity, and concentrations of aluminum and iron in the treated water, are studied. The tested coagulants can efficiently be applied for the treatment of drinking and sewage waters at low and high temperatures in a wide pH range of the waters to be treated.