Equilibrium and Kinetics of Arsenic (V) Sorption by Bone Char

Arsenic is a toxic element and may be found in natural waters as well as in industrial waters, which requires proper treatment before its use as drinking water. Present investigation aims to remove arsenate ions [As(V)] by bone char. Effect of solution pH, initial concentration, and contact time has been investigated. Kinetics reveal that removal of As(V) ion by bone char is very rapid in the first 30 min and equilibrium time in independent of initial As(V) concentration. The arsenate removal is strongly dependent on pH. Equilibrium studies show that As(V) ions have high affinity towards bone char at pH 10. Both Freundlich and Langmuir adsorption isotherms are well fitted to the experimental data. The results suggests that adsorption of As(V) removal on bone char is complex mechanism where both surface adsorption and intraparticle diffusion contribute to the rate determining step.