中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 33 No. 5 May 2023 |
（1. National Engineering Laboratory for Vacuum Metallurgy, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China;
2. State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China;
3. Silicon Material Industry Research Institution (Innovation Center) of Yunnan Province, Kunming 650093, China）
Abstract:A flotation recovery method of silicon from metallurgical-grade silicon-refined slag (silicate) using sodium silicate (SS) as the depressant was proposed. The solution chemistry, contact angle, and zeta potential measurements were used to understand the interaction mechanisms of SS on the silicate. With SS addition, the content of recovered silicon increased from (72.12±5.08) wt.% to (81.14±1.77) wt.%. During the flotation process, SS was hydrolyzed into strongly hydrophilic H2SiO3 and HSiO3-, which could be physically or chemically adsorbed with silicate. This adsorption allowed the contact angle of the silicate surface to decrease from 6.62° to 0°, indicating the decreasing floatability of the silicate.
Key words: metallurgical-grade silicon-refined slag; flotation; sodium silicate; depressant
