PARENT SESSION
SA6 - Sorption of Hydrophobic Pollutants
Chair: Koelmans, Albert Bart¹, ¹ P.O. Box 8080, Wageningen, Wageningen, The Netherlands
8:00 AM to 12:00 PM - Sunday, 17 November 2002
Room Ballroom B

(058) BIOSORPTION OF CHLOROPHENOLS BY ACCLIMATED RESIDENTIAL BIOMASS.

Antizar-Ladislao, Blanca^*,1,2, Galil, Noah¹, ¹ Technion-Israel Institute of Technology, Haifa, Israel, Israel² Imperial College at Wye, University of London, London, UK, UK

ABSTRACT- The biosorption behavior of phenol, 2-chlorophenol (2-MCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol by acclimated residential biomass was quantitatively characterized in this work, with emphasis on the effects of pH and hydrophobicity on the biosorption capacity of the target pollutants. The studies of isotherm of biosorption of phenol, 2-MCP, 2,4,6-TCP and PCP on biomass developed in sandy columns under bioremediation conditions were conducted by varying the initial concentrations, with a biomass concentration of 0.9 g/L. The biosorption isotherms were adequately described by Freundlich equation. The adsorption capacity (q_ads) of biomass increased significantly with decreasing pH. Different phenols affected the capacity constant K and the intensity parameter n of the Freundlich model following different trends at different equilibrium pH. The results of this study corroborate previously published results on biosorption of PCP by different biomass, nevertheless our results showed that the use of K or n for predicting the fate of different phenols at different pHs might be misleading, and the values of q_ads should be used in predicting models. The q_ads for the different investigated phenols were proportional to their hydrophobicity. Data obtained in this study and data collected from previous studies indicated that it may be possible to predict the biosorption of chlorophenols by using their octanol-water partitioning constants (K_ow). The results obtained in this study also give an idea of mechanisms of biosorption of phenols by biomass.

Key words: bioremediation, biosorption, pentachlorophenol, trichlorophenol