The fine crystals of ammonium tungstophosphate (AWP) exchanger were immobilized in the biopolymer consisting of calcium alginate (CaALG) gels. The uptake rate of Cs+ for the AWP-CaALG composite was fairly fast and the uptake percentage of Cs+ was above 90% within 30 min even in the presence of 5 M HNO3. In a wide HNO3 concentration region of 0.1 - 5 M, the distribution coefficient of Cs- for the composite was about 104 cm3/g, while those for other nuclides, Na+, Sr2-, Co2+, Eu3+ and Am3+, were less than 10 cm3/g. The uptake of Cs+ followed a Langmuir-type adsorption equation, and the maximum uptake capacity of Cs+ increase with the content of AWP immobilized in the composite. The trace amounts of 137Cs in the presence of 5 M NaNO3-1 M HNO3 were selectivity adsorbed on the composite column. The AWP-CaALG composite proved to be effective for the selective removal of radioactive cesium from waste solutions containing HNO3 and NaNO3.
ASJC Scopus subject areas
- Chemical Engineering(all)