Purification with hydrocyclone on low grade Sodium-bentonite from Xinjiang, China

College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao 266590, China

^* Corresponding author’s email: lu_xianjun @163.com

Abstract

Bentonite need to be purified to get montmorillonite content more than 80 % for industrial applications. The screen analysis indicates that montmorillonite in two Sodium-bentonites, which come from Xiazijie, Xinjiang uygur autonomous region, China, distribute mainly in the size fraction of -400 mesh. In this size fraction, the montmorillonite contents are 61.8 % and 60.0 %, yields are 88.5 % and 90.0 %, and the recoveries are 96.7 % and 93.7 %, respectively. According to the results of X-ray diffraction(XRD) and screen test, the two bentonites can be mixed together to be purified. With the 1^st stage hydrocyclone condition of pulp density 4 %, pressure 0.19 MPa, diameter of hydrocyclone 125mm, and with the 2^nd stage hydrocyclone in the condition of pressure 0.12 MPa and diameter of hydrocyclone 75mm, the concentrate with montmorillonite content of 82.3%, yield of 48.8 % and recovery of 63.7 % can be got. The 2^nd stage overflow product meets industry standard. The results show that hydrocyclone is the effective means for purification of this low grade Sodium-bentonite, but the Sodium-bentonite could be converted to Ca-bentonite after purification.