低冰镍硫-硝混酸浸出动力学  

Leaching Kinetics of Nickel Extraction from Low Nickel Matte by Sulfuric-Nitric Acid Mixture

作　　者：袁飞刚 刘旭恒 Yuan Feigang;Liu Xuheng(School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院

出　　处：《稀有金属》2019年第10期1075-1084,共10页Chinese Journal of Rare Metals

基　　金：国家重点研发计划项目(2018YFC1901603);国家重点基础研究发展计划项目(2014CB643405)资助

摘　　要：针对传统的镍硫化矿处理工艺存在吹炼过程中有价金属的损失问题,采用以低冰镍为原料湿法处理工艺可以使这一问题有效的解决。基于硫-硝混酸溶液在硫化矿浸出过程中的运用,对低冰镍在硫-硝混酸体系中的常压浸出过程开展了动力学研究,考察了搅拌速率、物料粒径、反应温度、酸浓度等条件对镍浸出过程的影响。结果表明:在实验条件下,镍的浸出反应过程符合未反应收缩核模型,反应过程中会在矿物表面会生成硫磺产物层,阻碍浸出剂向矿物内部扩散,使得低冰镍中镍的浸出反应控制步骤为内扩散控制,其表观活化能为87.63 kJ·mol^-1;低冰镍中镍的混酸常压浸出过程中,低冰镍粒径、硫酸浓度和硝酸浓度对应的反应级数分别为-2.00, 0.65和0.57,在此基础上建立了硫-硝混酸常压浸出低冰镍中镍的动力学方程。Aiming at the loss of valuable metals in the converting step in the conventional pyro-metallurgical treatment of nickel sulfide ore, the problem would be solved effectively by using low nickel matte as raw material in hydrometallurgical process. Based on the application of sulfuric-nitric mixture in the process for leaching sulfide ores, the leaching kinetics of nickel extraction from low nickel matte by atmospheric leaching with sulfuric and nitric acid was studied. The effects of agitation speed, particle size, temperature, sulfuric acid concentration and nitric acid concentration on the extraction rate of nickel were studied for exploring the kinetics law of nickel dissolution from low nickel matte. The experimental results showed that the leaching process followed the shrink-core model, further diffusion of the leaching agent into the interior of the mineral was prevented by sulfur product layer formed on the mineral surface during the reaction, the leaching efficiency of nickel was controlled by the internal diffusion, and the apparent activation energy was 87.63 kJ·mol^-1. In the internal diffusion control process, the reaction orders with respect to particle size, sulfuric acid concentration and nitric acid concentration were-2.00, 0.65 and 0.57, respectively. The kinetic equation for leaching of nickel from low nickel matte by sulfuric and nitric acid was established.

关 键 词：镍 低冰镍 混酸 浸出 动力学 

分 类 号：TF815[冶金工程—有色金属冶金]