Experimental and modeling study of Am-241 uptake by suspended matter in freshwater environment from southern Spain

Radiotracer experiments are presented on Am-241 uptake in natural aqueous suspensions from a reservoir and a river in SW Spain. The uptake was followed by measuring the Am-241 activity in water using a liquid scintillation technique. Experimental results revealed a three-step kinetics in the uptake, which could be satisfactorily described by a model of two parallel and reversible reactions followed by a consecutive weakly-reversible reaction. This paper also studies the effects of the concentration of suspended matter and the specific surface area on the kinetic transfer coefficients.