In situ sorption of technetium using activated carbon

The sorption of technetium in pertechnetate form on carbon has been investi gated. The sorption is pH dependent with maximal distribution coefficients, K-d, in the order of 10(6) at pH 2-4 for activated carbon with a grain siz e less than or equal to 100 mu m. The equilibrium time to reach such distri bution coefficient was about 5 h at room temperature. The exact mechanisms for the sorption are not fully understood but reduction of Tc by the carbon might be an important process. Technetium can effectively and rapidly (5 l min(-1)) be sorbed from very large volumes (several hundred liters) of env ironmental waters on commercial cartridge filters impregnated with activate d carbon. After incineration, the filters can be analyzed for Tc-99 by conv entional methods. (C) 2000 Elsevier Science Ltd. All rights reserved.