Purification of specularite by centrifugation instead of flotation to produce iron oxide red pigment

• Published in: International journal of minerals, metallurgy and materials Vol. 28; no. 1; pp. 56 - 65
• Main Authors: Zhang, Xi, Zhu, Shun-wei, Li, Yu-jiang, Li, Yong-li, Guo, Qiang, Qi, Tao
• Format: Journal Article
• Language: English
• Published: Beijing University of Science and Technology Beijing 2021; Springer Nature B.V; National Engineering Laboratory of Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China; School of Environmental Science and Engineering,Shandong University,Qingdao 266200,China%Zhengzhou Institute of Emerging Industrial Technology,Zhengzhou 450003,China%School of Environmental Science and Engineering,Shandong University,Qingdao 266200,China%National Engineering Laboratory of Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China
• Subjects: Beneficiation; Centrifugation; Centrifuges; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Concentration gradient; Corrosion and Coatings; Flotation; Glass; Iron compounds; Iron oxides; Ironmaking; Magnetic separation; Materials Science; Metallic Materials; Mineral processing; Minerals; Natural Materials; Purification; Raw materials; Reagents; Recovery; Red pigments; Reverse flotation; Scanning electron microscopy; Sulfuric acid; Surfaces and Interfaces; Thin Films; Tribology; centrifugal concentrator; specularite; iron oxide red pigment; reconcentration
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-020-2003-6

This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation. An iron concentrate with a grade of 65.1wt% and a recovery rate of 75.31% were obtained. A centrifugal concentrator served as the deep purification equipment for the preparation of iron oxide red pigments, and its optimal rotating drum speed, feed concentration, and other conditions were determined. Under optimal conditions, a high-purity iron oxide concentrate with a grade of 69.38wt% and a recovery rate of 80.89% were obtained and used as a raw material for preparing iron oxide red pigment. Calcining with sulfuric acid produced iron red pigments with different hues. Simultaneously, middlings with a grade of 60.20wt% and a recovery rate of 17.51% were obtained and could be used in blast furnace ironmaking. High-value utilization of specularite beneficiation products was thus achieved.