ADSORPTION OF Am-241, Cs-137 AND Sr-90 RADIONUCLIDESWITH BENTONITE-HUMIC ACID IMMOBILIZED YIELDAdsorpsi Radionuklida Am-241, Cs-137 dan Sr-90 dengan Hasil Imobilisasi Bentonit-Asam Humat
Adsorption of Am-241, Cs-137 and Sr-90 radionuclides to bentonite-humic acid immobilized yield have been
done. The aims of this study are (1) making of adsorbent materials from resulted immobilization humic acid into
bentonite mineral, and it’s characterization with spectroscopy infrared and X-ray diffractometer and (2) adsorption of
Am-241, Cs-137 and Sr-90 radionuclides into bentonite mineral as adsorbent at various pH. Experiments showed
that result of immobilization of bentonite-humic acid were optimum at 100 g bentonite, 60 g humic acid, 0.1 M
NaNO3 ionic strength, and 2.5 pH. At the optimum condition bentonite could be bonded by the functional COOH from
humic acid maximum equal to 75.2%. Base on infrared spectroscopy and X-ray diffractometer showed that humic
acid can immobilized into bentonite to form of bentonite-humic acid alloy. Application of adsorbent bentonite-humic
acid immobilized yield to adsorb radionuclides of Am-241, Cs-137 and of Sr-90, showed that can adsorb at the range
of pH 3 until 10. The phenomenon adsorption as species radionuclides was predicted by “Visual minteq” software.
By each the feeds of radionuclide 0.001 mMol/L, 0.1 M NaNO3 ionic strength and pH 5 showed that bentonite-humic
acid can adsorb radionuclides 98.50–99.1% of Am-241, Cs-137, and Sr-90.
Keywords: immobilisation, adsorption, infra red spectroscopy, X-ray diffractometer