It is necessary to utilize special techniques of separating submicron-size particles from other micron-size particles such as hydrocyclone and liquid-liquid separating. In this experimental work, separation of TiO2 and Al(OH)3 artificial mixture was investigated. Separation of submicron TiO2 particles from micron Al(OH)3 particles was carried out using a column bed filled with plastic fiber tubes or glass balls as matrixes. The Al(OH)3 particles have been mainly captured on the matrixes due to the hetero-coagulation effect. Large particles could be easily attached on matrixes because of strong lift force, and surface interactions between particle and matrix. The submicron TiO2 have been flowed out from the apparatus because of low collision possibility with the matrixes. As a result, submicron TiO2 particles were separated from micron size Al(OH)3 ones. This method could be applied to separate submicron TiO2 particles from Brazilian clay.
