Sorption behavior of strontium ions in humic acid solutions

详细

As shown by distribution, thermodynamic modeling, and dispersion analysis methods, the ability of freshly precipitated humic acid to take up Sr(II) ions is influenced by energy heterogeneity of its sorption sites, characteristic of both natural and synthetic samples. It is manifested in that the distribution coefficient K_d exceeds 1.9 × 10⁴ mL g^–1 at Sr(II) concentrations in solutions lower than 20 μg L^–1 but is equal to 1.9 × 10³ mL g^–1 at Sr(II) concentrations higher than 1 mg L^–1. In solutions with ultralow Sr(II) concentrations, humic acids exhibit high affinity for the humate complex Sr(HA) and do not interact with the complex Sr(HA)₂.