The effect of organics on the sorption of cobalt by glacial sand in laboratory batch experiments
Acetate, EDTA and organic compounds naturally present in groundwater at the Drigg in-situ radionuclide migration experimental site have been studied to assess their effect on the sorption of cobalt by glacial sand. Removing 56% of the natural organic material from the groundwater with DEAE cellulose increased the distribution ratio R(d) of cobalt by a factor of about two. EDTA had a dramatic effect even at low concentrations, reducing the R(d) by up to two orders of magnitude. At EDTA concentrations greater than 5mg/l there was no further reduction in sorption. EDTA was not itself sorbed, but formed a mobile complex with Co. Within the same period of equilibrium, the Rd values were higher when cobalt was allowed to reach equilibrium with the sand before adding EDTA. The desorption of cobalt from the mineral surface may be a rate-limiting step such that equilibrium was not achieved within the 14-day period of these experiments. Acetate had no effect on cobalt sorption in any of the experiments undertaken.
Bibliographic Reference: EUR 12532 EN (1990) 20 pp., FS, ECU 5
ISBN: ISBN 92-826-1084-5
Record Number: 199010301 / Last updated on: 1994-12-01
Original language: en
Available languages: en