Abstract:
This study investigated the effectiveness of Fe (III)-modified diatomite in removing hexavalent
chromium from aqueous solution as a low cost adsorbent under various conditions. Batch mode
experiments were conducted to study the effects of pH, contact time, adsorbent dose, and initial
concentration of adsorbate on the adsorption of hexavalent chromium. Adsorption equilibrium
was achieved after a contact time of 150 min. Hexavalent chromium adsorption was significantly
dependent on solution pH, and the optimum adsorption was observed at pH 2. Equilibrium
isotherm data were analyzed by the Langmuir and Freundlich models. Results indicated that
adsorption process obeys Freundlich isotherm model better than Langmuir. An estimated
maximum adsorption capacity of 1.96 mg/g was observed using Fe (III)-diatomite adsorbent at
optimal conditions of the batch experiment.
