Effects of Na_2SO_4 on iron and nickel reduction in a high-iron and low-nickel laterite ore

作     者：Xiao-ping Wang Ti-chang Sun Chao Chen Jue Kou 

作者机构：Key Laboratory of Ministry of Education of China for Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2018年第25卷第4期

页      面：383-390页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 08[工学] 0806[工学-冶金工程] 0708[理学-地球物理学] 080601[工学-冶金物理化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 51474018 and 51674018) 

主　　题：laterite ore ferronickel reduction magnetic separation 

摘      要：This study investigates the reactions of Na2SO4 and its effects on iron and nickel reduction in the roasting of a high-iron and low-nickel laterite ore through gas composition, X-ray diffraction, and scanning electron microscope analyses. Results showed that a reduction reaction of Na2SO4 to SO2 was performed with roasting up to 600℃. However, no clear influence on iron and nickel reductions appeared, because only a small amount of Na2SO4 reacted to produce SO2. Na2SO4 reacted completely at 1000℃, mainly producing troilite and nepheline, which remarkably improves selective reduction of nickel. Furthermore, the production of low-melting-point minerals, including troilite and nepheline, accelerated nickel reduction and delayed iron reduction, which is attributed to the concurrent production of magnesium magnetite, whose structure is more stable than the structure of magnetite. Reduction reactions of Na2SO4 resulted in weakening of the reduction atmosphere, and the main product of Na2SO4 changed and delayed the reduction of iron. Eventually, iron metallization was effectively controlled during laterite ore reduction roasting, leading to iron mainly being found in wustite and high iron-containing olivine.