Biosorption of Chromium (VI) Using Rice Husk Ash and Modified Rice Husk Ash

摘要

The purpose of this research was to investigate the adsorption ability and determine the suitable condition for adsorption of Chromium (Cr(VI)) in synthetic wastewater by Rice Husk Ash (RHA) and 0.1 NaOH modified RHA (MRHA). Adsorption abilities of the adsorbents in various conditions were examined in batch experiment. Contact time, pH, adsorbent dose and initial Cr(VI) concentration were varied to perform the adsorption conditions. The results indicated that all adsorption parameters affected to the adsorption of Cr(V) by RHA and MRHA. At the suitable condition (pH 2, contact time 180 min, room temperature, initial Cr(VI) concentration 10 mg L-1, adsorbent dose 40 g L-1, adsorbent size of 250-500 μm), the adsorption abilities of RHA and MRHA were 0.49 and 0.84 mg g-1 with removal efficiencies of 59.12 and 81.39%, respectively. Langmuir isotherm was found to better fit the experiment data rather than Fruendlich isotherm. As waste-recycle products, RHA and MRHA has been proved to be an effective adsorbent for Cr(VI) removal.