Collection of rare elements from geothermal water in Akita prefecture. Lithium adsorbent and it's application for Li collection from geothermal water.:Lithium adsorbent and it's application for Li collection from geothermal water

概要

論文の詳細を見る
Rare elements are present in geothermal water in Japan, and the existence of Lithium, Cesium and Boron has been confirmed by many reports. The authors have been studying adsorbents of high selectivity for these elements. As a result of this study, an oxygen-manganese-type-Li adsorbent has been developed, and we have estimated it's chemical characteristics. The adsorbent was prepared by heating a mixture of MnCO3 and LiOH H2O at 390°C for 4.5 hours. This adsorbent adsorbs only Li ions through an ion exchange reaction, and a suitable solution pH for Li adsorption occurs over pH7. Moreover, the performance of the adsorbent is influenced by the drying method used for the activation of the adsorbent. We attempted to collect Li from the geothermal water of Ounuma geothermal power plant in Akita prefecture. In the experiment, the adsorption-plate-method was utilized as the contact process between the adsorbent and the geothermal water. The results showed that the maximum efficiency of the Li adsorption reached 122.2mg/(m2 hour), and the adsorbent was heat resistant, with effective Li adsorption in spite of the high temperature (97°C).
環境資源工学会の論文