Kinetic Study of Sr²⁺ Sorption by Bone Char

Abstract

The effect of particle size, bone char mass, initial pH, and metal concentration on the kinetics of Sr²⁺ sorption by bone char was studied and discussed. Considering the sorbed amounts of Sr²⁺, solution pH changes, changes of Ca²⁺ concentrations and Ca/Sr molar ratios, with time, it was concluded that surface complexation reactions are dominant in the first, more rapid stage of the sorption process, while the contribution of the ion-exchange mechanism increases with time and becomes more significant in the second, slower phase. Under all investigated experimental conditions, the pseudo-second-order model was found to provide high correlation coefficients and the equilibrium amounts of Sr²⁺ sorbed comparable to the values obtained experimentally.

Keywords:

• Bone char
• kinetic models
• sorption kinetics
• Sr²⁺

ACKNOWLEDGEMENTS

This work was supported by the Ministry of Science and Environmental Protection of the Republic of Serbia, under Project No. 142050.