Abstract
It has been known by precedeing investigations that an agent synthesized from amorphous silica and hydrated lime (CSH) is effective for advanced treatment of animal wastewater (phosphate removal, color removal, and disinfection) and recovered CSH is reusable as posphorus fertilizer. The present study has clarified that the recovered CSH has ability of sorbing nonradioactive- and radioactive-cesium and nonradioactive strontium while nonused CSH has no sorbing ability. Though the reason why only recovered CSH has sorbing ability is unclear, following assumptions can be made for explain this phenomenon. For the case of cesium, it would be sorbed by electrical static force between surface of recovered CSH which electrical static cahrge might changed from plus to minus by sorbing anionic phosphate ion. For the case of strontium, it would be sorbed by ion-exchange reaction with calcium in hidroxyapatite formed in recovered CSH. It is subject of future investigation for examing effect of recovered CSH on transfer rate of radioactive cesium from soil to crop when applying it as fertilizer.
