title: Innovative methodology for recovering titanium and chromium from a raw ilmenite concentrate by magnetic separation after modifying magnetic properties.
abstract: Raw ilmenite concentrate containing Cr can be either as a resource or as one kind of the most hazardous solid waste. In order to recover titanium and chromium from the raw concentrate which was separated from the Promenade deposit, Gaza province, Mozambique, an innovative technology using modification of magnetic property followed by magnetic separation was proposed. Magnetic property, phase and surface morphology of the sample before and after oxidizing roasting were firstly characterized by magnetism, chemistry, XRD and MLA analyses to interpret the mechanism of oxidizing roasting of the ilmenite. Then, these factors such as oxidizing roasting temperature, residence time and magnetic induction affecting on magnetic separation performance were examined and the optimum process parameters were determined. A commercial concentrate containing 47.94% TiO2and 0.23% Cr2O3was obtained and the recovery of TiO2and Cr2O3was 78.52% and 5.42%, respectively. The tailing obtained was preliminarily concentrated by a high-intensity magnetic separator and a rough chromite concentrate was gained. In order to further purify the rough one, reducing roasting was carried out to transform the minerals containing hematite into the minerals containing magnetite, followed by a low-intensity magnetic separation. The effects of these parameters such as temperature, carbon powder dosage, holding time and magnetic induction on magnetic separation performance were investigated and the optimal conditions were determined. A concentrate containing 28.65% Cr2O3was obtained and the total recovery of Cr2O3was 84.18%.
authors.affiliation: State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China; Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China; KunMing Metallurgy Research Institute, Kunming 650093, China.
authors.forename: Jin-Fang
authors.initials: JF
authors.lastname: Lv
authors.affiliation: KunMing Metallurgy Research Institute, Kunming 650093, China.
authors.forename: Han-Ping
authors.initials: HP
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China; Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Tong
authors.affiliation: State Key Lab. Multi-Phase Complex System, Institute of Process Engineering, CAS, Beijing 100190, China.
authors.forename: Chun-Lin
authors.initials: CL
authors.lastname: Fan
authors.affiliation: Yunnan XinLi Nonferrous Metals Co., Ltd, Kunming 650100, China.
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China. Electronic address: yongxingzheng2015@yahoo.com.
authors.forename: Yong-Xing
authors.initials: YX
authors.lastname: Zheng
keywords: Chromite; Magnetic separation; Modification of magnetic property; Oxidizing roasting; Raw ilmenite concentrate; Reducing roasting