Effects of composition and structure of alginates on adsorption of divalent metals
Results of a series of experiments (on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of different composition and block structure) conducted in this systematic study of the effects of the composition and structure of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of theM/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu2+ ion decrease with the increase of the G-block or the average length of the G-block\((\bar N_G )\) and the total adsorption capacity of alginic acid is found to vary in the same order as theF MM(diad frequency) in alginate in the mixed solution of Sr2+, Ba2+ and Cd2+.
Key wordscomposition structure adsorption ion exchange divalent metal alginate seaweed
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