摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a cleaning material capable of effectively cleaning contaminated soil containing fluorine, boron, arsenic and heavy metals such as chromium, lead and selenium, and exhibiting only a small increase in the volume when mixed with contaminated soil. <P>SOLUTION: In the cleaning material, a hydroxide or an oxide of a rare earth element is adhered on the surface of metallic iron powder. The cleaning material can effectively clean contaminated soil containing fluorine, boron, arsenic and heavy metals such as chromium, lead and selenium, and exhibits only a small increase in the volume when mixed with contaminated soil. The adhesion of a hydroxide or an oxide of a rare earth element on the surface of metallic iron powder improves more the absorption capability of the hydroxide or the oxide of a rare earth element than in single use of the same amount of the hydroxide or the oxide of a rare earth element, as proved in examples. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |