有色金属(冶炼部分)

富钴结壳含有钴、镍等关键金属元素，其中钴最高含量可达0.8%～1.2%。富钴结壳经还原酸浸后，镍、钴、锰元素进入浸出液，浸出液中锰浓度显著偏高，而镍钴含量相对偏低。为短流程回收镍、钴，需通过差异化沉淀实现镍、钴与锰的初步分离。鉴于氢氧化镍钴（MHP）作为制备三元前驱体所需镍钴金属的重要中间产物之一，可优先通过沉淀氢氧化镍钴的方式实现大部分镍钴与锰的分离，剩余的镍钴通过硫化沉淀镍钴的方式与锰分离。以除铁后含高锰的富钴结壳还原酸浸液为原料，采用氢氧化钠作为沉淀剂制备氢氧化镍钴。在反应温度25℃、氢氧化钠流速4 mL/min、氢氧化钠浓度6～8 g/L、反应时间45 min条件下，镍、钴、锰沉淀率平均分别为76.89%、60.45%、1.14%，沉淀中镍、钴合计含量平均40.57%，锰平均含量10.18%。实现了锰与大部分镍、钴的初步分离，沉淀产物可直接对接主流三元前驱体生产体系，为海洋矿产资源利用提供了新思路。

Cobalt-rich crusts, also known as cobalt-rich ferromanganese crusts, are gradually becoming the focus of scientific research and industrial attention as a highly promising marine mineral resource. It is widely distributed on seamounts at water depths of 800–3 000 meters, and contains key metal elements such as nickel(0.3%–1.2%), cobalt(0.2%–0.8%) and manganese(15%–25%). These metal elements have important industrial value, especially in the battery field, which can be converted into battery-grade raw materials such as nickel sulfate and cobalt sulfate through smelting to provide a sustainable supply of metals for the ternary precursor, which is of great significance to alleviate the shortage of land resources and promote the development of new energy industry. Nickel, cobalt, and manganese are dissolved into the leaching solution after reductive acid leaching of cobalt-rich crusts. Manganese concentration in the leaching solution is significantly high, while the nickel and cobalt content are relatively low. In order to recycle nickel and cobalt in a short process, it is necessary to realize the preliminary separation of nickel,cobalt and manganese through differential precipitation. Given that nickel-cobalt hydroxide(MHP) is one of the important intermediates of nickel and cobalt metals required for the preparation of ternary precursors, separation of most of the nickel-cobalt from manganese can be achieved preferentially by precipitation of nickel-cobalt hydroxide,and the remaining nickel-cobalt is separated from manganese by precipitation of nickel-cobalt sulphide. This study utilizes high-manganese reductive acid leachate from iron-purified cobalt-rich crusts as raw material and employs sodium hydroxide as a precipitant to synthesize nickel-cobalt hydroxide. Under the optimized conditions of reaction temperature at 25 ℃, sodium hydroxide solution directly dripping into the feed solution, sodium hydroxide flow rate 4 mL/min, sodium hydroxide concentration 6–8 g/L, and reaction time 45 min, the average nickel, cobalt and manganese precipitation rate is 76.89%, 60.45% and 1.14% respectively, and the average content of nickel and cobalt combined in the precipitation is 40.57%, and the average manganese content is 10.18%. The preliminary separation of manganese from the majority of nickel and cobalt has been achieved, and the precipitated product can be directly integrated into mainstream ternary precursor production systems, offering a novel approach for the utilization of marine mineral resources. This study opens up new pathways for the comprehensive utilization of marine mineral resources. With the continuous development and refinement of technologies, cobalt-rich crusts are expected to play a more significant role in fields such as new energy and advanced materials in the future.