中文摘要：

为提高综合利用率,对大洋多金属结核碱浸进行预处理研究,考察大洋多金属结核高压低质量分数碱浸过程中Na OH初始质量分数、反应温度、液固比、浸出时间等因素对SiO_2溶出影响,并对高压碱浸脱硅动力学进行研究。研究结果表明：在浸出温度为180℃、质量分数为10%Na OH溶液、液固比为3.0：1.0条件下反应70 min,可制得118.51 g/L的Na2Si O3溶液,其余Na2Si O3以方沸石（Na（Si2Al）O6？H2O）形式析出,SiO_2高压浸出反应的表观活化能为50.08 k J/mol,遵循化学反应控制的收缩核模型。通过高压低质量分数碱浸可选择性浸出其中的SiO_2,并生成有良好吸附性能的方沸石,而不破坏有用金属元素晶格结构,所得浸渣锰质量分数为30.72%以上。

英文摘要：

In order to improve the comprehensive utilization, an alkali leaching pretreatment of ocean polymetallic nodules was studied. The effects of initial mass fraction of NaOH, leaching temperature, mass ratio of liquid-to-solid, leaching time, and the pressure leaching kinetic on the dissolution of silica were investigated during the low mass fraction of alkali leaching process of ocean polymetallic nodules with low mass fraction of NaOH solution under high pressure. And the high pressure alkali leaching kinetics of desilication was also investigated. The results show that the mass concentration of Na2SiO3 in the leachate reaches 118.51 g/L with the leaching temperature of 180 oC, the mass fraction NaOH of 10%, the liquid-to-solid mass ratio of 3.0：1.0 and the leaching time of 70 min, and the rest of Na2SiO3 changes to analcime Na（Si2Al）O6？H2O. The apparent activation energy of SiO2 in the high pressure leaching reaction is 50.08 kJ/mol, which follows the shrinking core model with surface chemical reaction control. Through the low mass fraction of alkali leaching with high pressure leaching, SiO2 can be selectively leached by the leaching process with low mass fraction of NaOH solution under high pressure, while analcime with high adsorption property can be produced. At the same time, the lattice structures of useful metal elements will not be damaged, and the mass fraction of Mn of residue reaches above 30.72%.