褐铁型高锰红土矿微波预处理-酸浸提取镍钴

以褐铁型高锰红土矿为研究对象，采用微波预处理-酸浸工艺提取Ni、Co。对矿样物相组成及Ni、Co、Fe、Mn等主要元素赋存状态进行X射线衍射（XRD）和电子探针（EPMA）表征，研究常压条件下硫酸浓度、浸出时间、浸出温度等因素对微波预处理矿样中Ni、Co浸出效果的影响。结果表明：矿样中镍钴品位较高但物相结构复杂，Ni主要与Mn以NiMn₃O₇?3H₂O形式赋存，Co伴生于针铁矿和碱式氧化锰中；在最优浸出条件下，即硫酸浓度300g/L、浸出时间5h、浸出温度90℃、液固比6∶1（以mL/g计）、搅拌速度280r/min，Ni、Co浸出率分别达到95.4%和97.1%，与相同浸出条件下未经微波处理的矿样相比，Ni、Co浸出率分别提高了69.4%和70.1%，实现镍钴的高效浸出；对比微波处理前后矿样XRD图谱，发现微波作用下矿物中Ni、Fe、Mn等物相结构出现明显转变，利于Ni、Co酸浸反应。

Extraction of nickel and cobalt by microwave pretreatment-acid leaching of limonite high manganese laterite ore

Taking the Limonite high manganese laterite ore as the research object, Ni and Co were extracted by microwave pretreatment-acid leaching process. X-ray diffraction (XRD) and Electron probe microanalysis (EPMA) were used to characterize the phase composition and the occurrence state of Ni, Co, Fe, Mn and other major elements in ore samples. The effects of sulfuric acid concentration, leaching time and leaching temperature on the leaching effect of Ni and Co in microwave pretreatment ore samples were studied. The results showed that the nickel-cobalt grade in the ore sample was high but the phase structure was complex. Ni was mainly present in the form of NiMn₃O₇·3H₂O with Mn. Co was associated with goethite and basic manganese oxide. Under optimal leaching conditions with sulfuric acid concentration 300g/L, leaching time 5h, leaching temperature 90℃, liquid-solid ratio (mL/g) 6∶1 and stirring speed 280r/min, Ni and Co leaching rates were reached 95.4% and 97.1%, respectively. Compared to the non-microwave treated ore sample under the same leaching conditions, Ni and Co leaching rates increased by 69.4% and 70.1%, respectively. achieving high-efficiency leaching of nickel-cobalt. Comparing the XRD patterns of the ore samples before and after microwave treatment, it was found that the phase structure of Ni, Fe and Mn in the minerals changed significantly under the action of microwave, which was beneficial to the Ni and Co acid leaching reactions.