Removal of chromium (VI) ions from aqueous solutions by using Kiwi shell

Kiwi shell, an waste material, was investigated as an adsorbent for the removal of Cr(IV) toxic metal from aqueous solutions. Batch experiments have been performed as a function of pH, contact time, dose of sorbent, initial Cr(IV) concentration, strength ionic and temperature. The experiments showed that the adsorption process was quick and the equilibrium attained within 20 min. Evaluation using Langmuir gave sorption capacity 6.23 mg g-1. Chromium uptake by Kiwi shell was best described by pseudo-second order model. Using the equilibrium concentration constants obtained at different temperatures, various thermodynamic parameters, have been calculated. The results indicated that Chromium adsorption was feasible, spontaneous, and exothermic.

Keywords:

Removal , Chromium , Kiwi shell , kinetics