LIANG Huayin, NIE Xin, WANG Yongqing
(School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China)

Abstract: The bleaching and iron removal by reduction-complexation method was experimented using ionic rare earth tailings from Southern China as raw material. The effects of reduction-complexation method on pH value, reaction temperature, dosage of sodium hyposulfite, bleaching time, dosing frequency, and oxalic acid dosage were studied. The results show that the appropriate processing conditions are as follows: pH, 3; reaction temperature, 50 ℃; dosage of bleaching powder, 3%; bleaching time, 60 min; dosing frequency, 4;oxalic acid dosage, 2.5%. Under the optimized processing conditions, the whiteness of the bleached tailings increases from 57.7 to 72.3 by the reduction-complexation method, while the Fe₂O₃ content reduces from 2.11% to 1.43%.
Key words: ionic rare earth tailings; bleaching and iron removal; reduction-complexation method