Practical Study on the Simultaneous Recovery System of Rare Metals from Deep Ocean Water

在本研究中，将锂、锶、铷和钼的相互回收体系与单独的吸附剂杂交，开发了海水中稀有金属的同时回收体系。我们得到了以下结果。(1)开发了锶、铷和钼的无机离子尺寸可识别吸附剂，分别为Sr的沸石型吸附剂、Rb的MnO_2型吸附剂和Mo的赤铁矿型吸附剂。(2)通过测定金属离子的吸附平衡和动力学来阐明吸附机理。通过测定金属离子吸附量的时间过程，阐明了pH、金属离子浓度和吸附剂用量对金属离子吸附速率的依赖关系。(3)新型吸附剂造粒方法的开发利用二氧化硅、氧化铝等无机粘结剂，开发了新型粉状吸附剂造粒方法。(4)模拟深海水体中稀土金属相互回收的基础研究，利用模拟深海水体分别选择性回收Li、Sr、Rb和Mo。参考2005年底在东京冲绳县-鸟岛站采样的深海水成分分析结果，制作了模拟深海水。(5)模拟深海中稀有金属同时回收的基础研究利用实验室规模的实验装置，对模拟深海中4种元素进行了同时选择性回收。其中Li和Sr的回收率较高，而Rb和Mo的回收率较低。目前仍在继续研究提高效率的方法。(6)同时选择性回收海水中稀有金属的实用化研究在佐贺大学海洋能源研究所的海水中稀有金属回收中试装置上进行了同时回收Li、Sr、Rb和Mo的实用化实验，评价了吸附剂回收效率的时间过程。其中Li的回收率较高，而Sr、Rb和Mo的回收率较低。目前仍在继续研究提高效率的方法。少

In this study, the simultaneous recovery system of rare metals from seawater has been developed by hybridizing the mutual recovery system of lithium, strontium, rubidium and molybdenum with individual adsorbents. We have the following results.(1) Development of inorganic ion size-recognizable adsorbents for Sr, Rb and Mo Zeolitic adsorbent for Sr, MnO_2 type adsorbent for Rb and hematite type adsorbent for Mo were developed, respectively.(2) Elucidation of adsorption mechanism by measuring the adsorption equilibria and kinetics of metallic ionsThe dependencies of pH and concentrations of metallic ions and adsorbent amount on adsorption rates of metallic ions were elucidated by measuring the time courses of the adsorption amount of metallic ions.(3) Development of novel granulation method of adsorbentsA novel granulation method of powder adsorbents were developed by using inorganic binders suchas silica and alumina.(4) Fundamental study of mutual recovery of rare metals from simulated d … More eep ocean waterIndividual selective recovery of Li, Sr, Rb and Mo were carried out by using simulated deep ocean water. The simulated deep ocean water was prepared by referring the component analysis results of deep ocean water sampled at Okino-Torishima site in Tokyo at the end of 2005. The optimization of operation conditions such as flow rate of supplying solution, scrubbing and elution processes were carried out for suppressing the impediment of coexisting ions(5) Fundamental study of simultaneous recovery of rare metals from simulated deep ocean waterSimultaneous selective recovery of four elements from simulated deep ocean water was carried out by using the lab-scale experimental apparatus. In these elements, Li and Sr were recovered with high recovery efficiencies, while Rb and Mo were limited to low recovery efficiency. This is still continuing to study the enhancement of efficiencies.(6) Practical study of simultaneous selective recovery of rare metals from seawaterPractical experiments of simultaneous recovery of Li, Sr, Rb and Mo were carried out by using a pilot plant of rare metal recovery from seawater in Institute of Ocean Energy of Saga University at Imari, Saga for evaluating the time course of recovery efficiencies of adsorbents, disabilities. In these elements, Li were recovered with high recovery efficiencies, while Sr, Rb and Mo were limited to low recovery efficiency. This is still continuing to study the enhancement of efficiencies. Less