Development of a Sulfuric Acid Leach Process of Manganese Nodules at Moderate Temperatures

本研究已进行了0.2公斤的小型试验，并开发了一种新的工艺流程，使镍砷和镍；结核(CM-17，0.2 kg，-40+60目，Cu0.25，Ni0.39，Co0.33，Fe11.7，Mn18.5wt%)在373 K，2L，2L，373 K，450转/分，搅拌4小时，浸出。铜、镍、钴的浸出率分别为87.0%、97.0%和21.0%。这些值高于烧杯规模测试中的值。浸出液中铜、镍、钴的浓度分别为0.22、0.35、0.07g/L。将钙泥(Ca&lt；CO_3&Gt；93.6%)逐步加入到浸出液中，直至pH达到3.0，~lt；Fe~(3+)&Gt；和&lt；Al~(3+)&Gt；的脱除率分别为98%和21%。在363K下，在1L母液中加入废铁(Fe98.4%)，铜的回收率可达99.5%，沉淀物中的铜含量为75%。在363K下，用还原铁粉和&lt；Ni_3&gt；&lt；S_2&gt；和CoS混合硫化物回收镍和钴的新工艺。最佳工艺条件为：358~368K，3[Fe]/[&lt；Ni^(2+)&gt；]摩尔比1.25，&lt；H_2&gt；S流量0.9L/[&lt；Ni^(2+)&gt；g/L]小时。镍和钴的回收率在1小时分别达到99.5%和90%。

The research works have been performed on a bench-scale test of 0.2 kg and the development of a new process concentrating Ni as <Ni_3> <S_2> . Nodule(CM-17, 0.2 kg, -40 +60mesh, Cu 0.25, Ni 0.39, Co 0.33, Fe 11.7, Mn 18.5 wt%) was leached in a 2N <H_2> <SO_4> of 2L at 373 K for 4hr stirring at 450rpm. The percentages of leached Cu, Ni, and Co were 87.0, 97.0, and 21.0 %, resp. These valued were higher than those in the beaker-scale test. The Cu, Ni, and Co concentrations in the leach liquor were 0.22, 0.35,and 0.07 g/L, respectively. Calcareous mud (Ca <CO_3> 93.6%) was added gradually to the leach solution until the pH reached 3.0 and <Fe^(3+)> and <AL^(3+)> were removed 98 and 21 %, resp. without coprecipitation of Cu, Ni, and Co. Then, scrap iron(Fe 98.4 %) was added to 1L of the mother liguor at 363 K. The recovery of Cu reached 99.5 % and the Cu content in the precipitate was 75 %. A new process for the recovery of Ni and Co as a mixed sulfide of <Ni_3> <S_2> and CoS have been developed with reduced iron powder and <H_2> S at 363 K. The optimum conditions were as follows:358-368 K, 3[Fe]/[ <Ni^(2+)> ] molar ratio 1.25, and <H_2> S flow rate 0.9L/[ <Ni^(2+)> g/L]hr. The recoveries of Ni and Co reached 99.5 and 90 % at 1 hr, resp.