ENVR 151 |
| Toxic metals are discharged by a number of industrial processes. Their presence in the environment is a major threat to plant, animal and human life due to their tendency to build up to toxic levels in tissues and, therefore, legislation is demanding increasingly lower levels of discharge in municipal and industrial effluents. The most commonly used procedures for the treatment of effluents containing heavy metals include chemical precipitation, evaporation, ion exchange and membrane separation. Techno-economic considerations, however, limit their wide-scale applications. Therefore, the need for the development of economical, effective and safe methods for toxic metals' removal has led to the search for alternative procedures. In this contest, we have developed of a low-cost biosorbent from orange peel waste (OPW) of the fruit industry. Orange waste contains cellulose, pectin, hemi-cellulose, pigments and other low molecular weight compounds like limonene and so on, which have many active binding sites (functional groups of carboxyl and hydroxyl) for toxic metals. The OPW has been successfully tested for the decontamination of wastewater containing heavy metals. The present investigation shows that OPW takes up a substantial amount of Pb2+ ions from aqueous solution. IR study, potentiometric titration, kinetics models and Langmuir and Freundlich isotherms of raw OPW depectinated OPW and pectin extracted from OPW have been employed to understand the sorption mechanism. The potential performance of OPW as a new metal biosorbent and its sorption mechanism will be discussed. |
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General Papers
6:00 PM-8:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Environmental Chemistry |