(中南大學(xué) 冶金與環(huán)境學(xué)院，長(zhǎng)沙 410083)
摘 要: 以海底多金屬結(jié)核資源為原料，采用硫酸浸出-凈化除雜-配合沉淀的工藝制備三元正極材料前驅(qū)體Ni0.5Co0.2Mn0.3(OH)2。在硫酸浸出過程中，考察溫度、液固比、硫酸濃度、浸出時(shí)間對(duì)鎳、鈷、錳浸出率的影響，探究鎳、鈷、錳元素浸出動(dòng)力學(xué)。結(jié)果表明：在溫度200 ℃、液固比6:1、硫酸濃度350 g/L、浸出時(shí)間90 min條件下，鎳、鈷浸出率達(dá)到95%以上，錳浸出率僅為6.43%，實(shí)現(xiàn)鎳、鈷與少部分錳的浸出。當(dāng)溫度在120~200 ℃之間時(shí)，錳浸出過程受擴(kuò)散控制，表觀活化能為10.64 kJ/mol；鎳、鈷浸出過程受混合控制，表觀活化能分別為27.60和38.16 kJ/mol。浸出液經(jīng)黃鈉鐵礬法除鐵、硫化錳除銅、碳酸氫銨水解沉淀除鋁、P204萃取除鈣后，采用P204萃取鎳、鈷、錳，得到硫酸鎳、硫酸鈷和硫酸錳的混合液，經(jīng)調(diào)節(jié)鎳鈷錳比例后，用氨水-氫氧化鈉配合共沉淀法制備得到球形的Ni0.5Co0.2Mn0.3(OH)2，可用于制備三元正極材料。
關(guān)鍵字: 三元前驅(qū)體；正極材料；海底多金屬錳結(jié)核；浸出；除雜
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:With seafloor polymetallic nodules as raw materials, ternary cathode material precursor Ni0.5Co0.2Mn0.3(OH)2 was prepared through a process of sulfuric acid leaching-purification-precipitation. In the process of sulfuric acid leaching, the effects of temperature, liquid-solid ratio, sulfuric acid concentration and leaching time on the leaching efficiency of nickel, cobalt and manganese were investigated. The leaching kinetics of nickel, cobalt and manganese were explored. The results show that the leaching efficiencies of nickel and cobalt are greater than 95%, and that for manganese is only 6.43% under the conditions of temperature of 200 ℃, liquid-solid ratio of 6:1, sulfuric acid concentration of 350 g/L, and leaching time of 90 min. Nickel and cobalt are selective leaching. At 120-200 ℃, the leaching process of Mn is controlled by diffusion with apparent activation energy of 10.64 kJ/mol. The leaching processes of Ni and Co are controlled by both diffusion and chemical reaction with apparent activation energy of 27.60 and 38.16 kJ/mol, respectively. Fe3+ ion in the leaching liquor is removed using sodium jarosite, copper is removed with manganese sulfide, and aluminum is precipitated as aluminum hydroxide as well as calcium is extracted by P204. A mixture of pure nickel sulfate, cobalt sulfate and manganese sulfate is then obtained through solvent extraction. The spherical Ni0.5Co0.2Mn0.3(OH)2, ternary cathode material precursor, is prepared by ammonia-sodium hydroxide coprecipitation after adjusting the molar ratio of nickel sulfate, cobalt sulfate and manganese sulfate.
Key words: ternary precursor; cathode material precursor; seafloor polymetallic nodules; leaching; impurity removal
