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

研究工作已在0.2kg小型试验台上进行，并开发了一种新的富集镍的工艺<Ni_3><S_2>。在373 K、450 rpm搅拌下，在2L的2N中浸提诺卡氏菌（CM-17，0.2 kg，-40 +60目，Cu 0.25，Ni 0.39，Co 0.33，Fe 11.7，Mn 18.5wt%<H_2><SO_4>）4小时。Cu、Ni、Co的浸出率分别为87.0%、97.0%、21.0%。这些值均高于烧杯规模试验。浸出液中Cu、Ni和Co的浓度分别为0.22、0.35和0.07 g/L。在<CO_3>浸出液中逐渐加入钙泥（Ca 93.6%），直至pH达到3.0，&lt;Fe^（3+）&gt;和&lt;Al^（3+）&gt;的去除率分别为98%和21%。然后，在363 K下，将铁屑（Fe 98.4%）加入到1 L母液中。铜的回收率达99.5%，沉淀物中铜含量为75%.研究<Ni_3><S_2>了在363 K下，以还原铁粉和硫为原料，从镍钴混合硫化物<H_2>中回收镍钴的新工艺。最佳条件为：358-368 K，[Fe]/[ &lt;Ni^（2+）&gt; ]摩尔比为1.25，<H_2>S流量为0.9L/[ &lt;Ni^（2+）&gt; g/L] hr，1hr时Ni和Co的回收率分别达到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.