Optimisation of process parameter using Response Surface Methodology to recover ceramic materials from bauxite mining waste rocks

摘要

The bauxite mining waste rocks is also referred as Partially LaterizedKhondalite (PLK) a rock that is generated during mining of bauxite. PLK rocks that associated with kaolinized khondalite rocks are being generated and dumped at the mine site as waste material or sometimes used for back filling of abandoned mines.These rocks contain 36.14% A12O3, 29.57% SiO2, 15.87% of Fe2O3, 2.37% of TiO2and 15.60% LOI.This rock cannot be used as a valuable material for any industry due to the presence of high iron content as well as not suitable for Bayer's process as it contains reactive silica. Physical methods such as magnetic separation, flotation, scrubbing etc. are not fully successful for removal of iron from PLK rocks. Leaching techniques are the only alternative method to minimize iron content in it. This present paper deals with leaching studies of mining waste PLK rocks during bauxite mining, is carried out on different parameters like temperature, concentration, pulp density and time. The brightness of the product is increased to 80% which is desirable for high valued ceramicproducts. Hence, the optimized parameters of the leaching can be scaled up to the industrial trials for further viability.