Author
BANSODE, RISHIPAL - LSU AG CENTER | |
LOSSO, JACK - LSU AG CENTER | |
Marshall, Wayne | |
RAO, RAMU - LSU AG CENTER | |
PORTIER, R - LSU ENVIRON.STUDIES |
Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/7/2003 Publication Date: 6/4/2003 Citation: Bansode, R.R., Losso, J.N., Marshall, W.E., Rao, R.M., Portier, R.J. 2003. Adsorption of metal ions by pecan shell-based granular activated carbons. Bioresource Technology. 89:115-119. Interpretive Summary: The utilization of agricultural by-products, such as pecan shells, for activated carbon production add value to waste products and may provide a potentially cheap alternative to existing commercial carbons. In this study, pecan shell carbons were evaluated for their ability to adsorb the metal ions, copper, lead and zinc, from a laboratory prepared wastewater. The results obtained showed that the pecan shell carbons prepared by steam activation and especially by acid activation were better at removing these metals than a commercial coal-based carbon. These results indicate that pecan shell carbons can potentially replace typical coal-based activated carbons in treatment of metal ion contaminated wastewater. Technical Abstract: The present investigation was undertaken to evaluate the adsorption effectiveness of pecan shell-based granular activated carbons (GACs) in removing metal ions (Cu2+, Pb2+, Zn2+) commonly found in municipal and industrial wastewater. Pecan shells were activated by phosphoric acid, steam or carbon dioxide activation methods. Metal ion adsorption of shell-based GACs was compared to the metal ion adsorption of a commercial carbon, namely, Calgon's Filtrasorb 200. Adsorption experiments were conducted using solutions containing all three metal ions in order to investigate the competitive effects of the metal ions as would occur in contaminated wastewater. The results obtained from this study showed that acid-activated pecan shell carbon adsorbed more lead ion and zinc ion than any of the other carbons, especially at carbon doses of 0.2% to 1.0%. However, steam-activated pecan shell carbon adsorbed more copper ion than the other carbons, particularly using carbon doses above 0.2%. In general, Filtrasorb 200 and carbon dioxide-activated pecan shell carbons were poor metal ion adsorbents. The results indicate that acid- and steam-activated pecan shell-based GACs are effective metal ion adsorbents and can potentially replace typical coal-based GACs in treatment of metal contaminated wastewater. |