Removal of Metals and Radionuclides Using Apatite and Other Natural Sorbents

Treatment of waste water for removal of low levels of actinides, particularly plutonium, uranium, and americium, and hazardous metals has been and continues to be a challenge. This study evaluated the use of apatite and other natural materials for use as sorbents to treat water streams containing As, Am, Pu, Se, Tc, and U. Nine sorbents were tested including natural and synthetic apatites, tri-calcium phosphate, bone char, and activated magnetite. The sorption properties were tested in batch studies and in column tests. There was moderate sorption of As, Se, Sr, Cs, and Tc, but very good removal of U and Pu by the phosphate adsorbents. The Am results were inconclusive. The synthetic apatites had higher capacities than the natural apatites from phosphate rock and fish bones.