REMOVAL OF Cr (VI) FROM AQUEOUS SOLUTION USING GRANULAR ACTIVATED CHARCOAL PREPARED FROM CORDIA MACLEODII TREE BARK AND SURFACE MODIFIED GRANULAR ACTIVATED CHARCOAL: A COMPARATIVE STUDY VIA SPECTROSCOPIC CHARACTERIZATIONS

Granular Activated Charcoal (GAC) was prepared by using Cordia macleodii tree bark and was tested for the removal of Chromium (VI). All the experiments were carried out in batch process. To enhance its metal ions adsorption capacity, activated carbons were impregnated with the chelating agents like sodium dodecyl sulfate (SDS), sodium dodecyl benzeneulfonate (SDBS) and Dioctyl sulfosuccinate sodium salt ( DOSS) and were tested for the removal of Chromium (VI). Adsorption isotherms of Chromium ions in aqueous solution have been experimentally measured on both modified and unmodified charcoal. Effects of adsorbent dose, pH, contact time, initial concentration and temperature were investigated on removal of Chromium (VI). Adsorption was confirmed by SEM - EDAX and FTIR morphological analysis. The adsorption data were fitted well by Langmuir adsorption isotherm. Approximately 96.54% of hexavalent Chromium was remo ved at pH 2 within 3 hr. It was found that chemically modified GAC with chelating agents demonstrated better Chromium (VI) removal capabilities as compared to pure adsorbents in terms of their adsorption rate. On the basis of present studies, it can be con cluded that granular activated charcoal impregnated with chelating agents has a higher Chromium (VI) adsorption capacity.