硝酸根氧化高压硫酸浸出红土镍矿  

High-Pressure Sulfuric Acid Leaching of Laterite Ores Using Nitrate Ion as an Oxidant

作　　者：马保中[1,2] 杨玮娇[1,2] 王硕[1] 杨卜[2] 王成彦[1,3] 

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093 [2]北京矿冶研究总院冶金研究所,北京100160 [3]北京科技大学冶金与生态工程学院,北京100083

出　　处：《稀有金属》2016年第7期715-720,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金青年基金(51304023);国家自然科学基金云南省联合基金(U1302274);国家自然科学基金面上项目(51274044)资助

摘　　要：以硝酸镁为氧化剂系统研究了硝酸根存在下红土镍矿在硫酸体系中的高压浸出情况。通过单因素条件实验详细考察了硝酸镁添加量、初始硫酸酸度、反应温度、保温时间和液固比对浸出结果的影响,并得到最优浸出工艺条件:硝酸镁加入量0.06 g·g^(-1),初始酸度140 g·L^(-1),反应温度220℃,保温时间60 min,液固比2 ml·g-1。在上述最优工艺条件下进行综合试验,取得了良好的浸出结果,实现了镍、钴和铁的选择性浸出,镍、钴浸出率分别为90.9%和91.7%,而铁浸出率低至2.2%。最后借助X射线衍射(XRD)、反射显微镜及化学物相分析,对新体系下浸出过程机制进行了研究,该体系中浸出过程为溶解—氧化—沉淀机制。添加硝酸根较传统硫酸高压浸出省酸,经计算利用该技术处理1 t红土矿可节省H2_SO_4大约160 kg。Laterite ore was treated by sulfuric acid pressure leaching using nitrate ion from Mg（ NO3 ）2 as an oxidant. Experiments were conducted in order to determine the optimum conditions by studying various parameters, including Mg（ NO3 ）2 dosage, initial a- cidity, reaction temperature, duration and liquid/solid ratio. The optimal conditions were Mg（ NO3 ）2/ore mass ratio of 0.06 g g-1, initial acidity of 140 g.L-1 , reaction temperature of 220 ℃, duration of 60 min and liquid/solid ratio of 2 ml g-1. Leaching experi- ments conducted under the proposed optimal conditions showed that nickel, cobalt and iron extraction rates were 90.9%, 91.7% and 2.2% , respectively. X-ray diffraction （XRD）, reflecting optical microscope, and chemical phase analysis were used to study the leac- hing mechanism of this new technology. The leaching process in this system corresponded to a dissolution-oxidation-precipitation mech- anism. A calculated savings in acid consumption of about 160 kg of sulfuric acid per ton of ore could be obtained, which suggested that lower acid consumption was needed compared with the traditional high pressure sulfuric acid leaching method.

关 键 词：红土矿 硝酸镁 硫酸 混合体系 高压浸出 

分 类 号：TF815[冶金工程—有色金属冶金] TF803.21