17562

Active Carbons from Chemically Mediated Pyrolysis of Agricultural Wastes: Application in Simultaneous Removal of Binary Mixture of Benzene and Toluene from Water

Lori J. A نويسنده , Lawai A. 0. نويسنده , Ekanem E. J. نويسنده

411

418

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Active carbons were produced from bagasse, millet and sorghum straws by chemical activation with ~PO4יCarbon precursors with particle size of! 180 11m were used, in order to overcome difficulties caused by low density and high ash content. The influence of preparation conditions (temperature, residence time, and acid impregnation ratio) on the yield of the active carbons was examined. The impregnation ration which was controlled by varying the proportion of~P04 used for the activation had a strong influence on the yields of the carbons. The pyrolysis temperature was varied in the range 100-450 "C, but equilibrium yields ofthe active carbons were highest at 450C with optimum impregnation ratio ofI 3.6. The potential ofthe active carbons as efficient and economical means ofremoving mixture ofaromatic hydrocarbon contaminants from water was indicated by the complete removal ofobjectionable odor from contaminated water samples containing 35.1348 rug/ernי benzene and 34.8534 mg/cmי Toluene, which are known carcinogens. Spectrophotometric determinations ofthe two solutes in the remediate water samples indicated slow but steady adsorption ofthe benzene/toluene mixture on the active carbons.

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