Sorption of Sr-85 and Am-241 from liquid radioactive wastes by alginate beads

Environmental studies are confronted with a challenging task to develop appropriate low cost technologies for treatment of liquid wastes. Conventional methods for removing metals from aqueous solutions include chemical precipitation, chemical oxidation or reduction, ion exchange, fi ltration, electrochemical treatment, reverse osmosis, membrane technologies and evaporation recovery. However, these processes may occur to be ineffective or extremely expensive, especially when the metals in solution are in the concentration below 1 mg·L–1 [1]. Another major disadvantage of the conventional treatment technologies is the production of great amounts of toxic sludge which disposal/treatment is a costly, non ecofriendly problem. Therefore, reduction of toxic and/ or radioactive metals to an environmentally safe level in a cost effective and environment-friendly way is of great importance. In a view of the above, natural sorbents of the biological origin have emerged as a prospective option [2, 3]. Biopolymers of alginic acid and its derivatives are got from two main sources: from various types of brown seaweed and from two forms of bacteria, Pseudomonas and Azotobacter. They show different structural and chemical properties depending on the season of their harvesting and on the growth conditions. However, all of these polymers form linear binary copolymers formed by 1–4-linked -Dmannuronic (M) and -L-guluronic (G) residues Sorption of Sr-85 and Am-241 from liquid radioactive wastes by alginate beads Agata Oszczak, Leon Fuks