当前位置: X-MOL 学术Min. Metall. Explor. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Kinetics of Atmospheric Leaching from a Brazilian Nickel Laterite Ore Allied to Redox Potential Control
Mining, Metallurgy & Exploration ( IF 1.5 ) Pub Date : 2020-10-07 , DOI: 10.1007/s42461-020-00310-w
A. L. A. Santos , E. M. A. Becheleni , P. R. M. Viana , R. M. Papini , F. P. C. Silvas , S. D. F. Rocha

The kinetics of atmospheric sulfuric acid leaching from a Brazilian nickel laterite ore was assessed using distinct reducing agents and ore mineralogy. This transitional ore contains 1.63% Ni distributed as 1.27% in coarse size (− 500 + 150 μm), mainly as silicates (lizardite and chlorite — 28.6%), and 2.06% in the fines fraction (− 75 μm), mainly as iron oxy-hydroxides (goethite and hematite — 49%). The effects of temperature, acid concentration, reducing reagent type, and concentration were evaluated. The − 75 μm fraction limited the leaching efficiency and the use of reducing media with thiosulfate improved leaching and Ni-Fe selectivity. However, at constant E h of 626–743 mV and a pH range between 0.2 and 1.1, no substantial rise in metals extraction, except for Co and Mn, has been observed. In order to determine the process control at 95 °C, two regions in the extraction curves were used in combination with the shrinking core model. Control by porous diffusion was observed and the kinetic constant was found to be in the order k Fe

中文翻译:

巴西红土镍矿的大气浸出动力学与氧化还原电位控制相关

使用不同的还原剂和矿石矿物学评估了从巴西红土镍矿石中浸出常压硫酸的动力学。这种过渡矿石含有 1.63% 的镍,分布为 1.27% 的粗粒度 (- 500 + 150 μm),主要为硅酸盐(蜥蜴矿和绿泥石 — 28.6%),以及 2.06% 的细粉部分 (- 75 μm),主要为铁羟基氧化物(针铁矿和赤铁矿 — 49%)。评估了温度、酸浓度、还原剂类型和浓度的影响。− 75 μm 级分限制了浸出效率,使用硫代硫酸盐还原介质可提高浸出率和 Ni-Fe 选择性。然而,在 626-743 mV 的恒定 E h 和 0.2 和 1.1 之间的 pH 值范围内,除了 Co 和 Mn 之外,没有观察到金属提取的显着增加。为了确定 95 °C 时的过程控制,提取曲线中的两个区域与收缩核心模型结合使用。观察到多孔扩散的控制,发现动力学常数在 k Fe 的数量级
更新日期:2020-10-07
down
wechat
bug