Kinetic Study of n-Hexane Biodegradation by an Isolated Fungal Consortium from a Biofilter

The kinetic study of a pollutant biodegradation is considered as one of the main steps in characterization of a biofilter performance. In this research, an unidentified fungal consortium which had been previously isolated from a compost biofilter treating n-hexane and toluene vapors, was used to remove n-hexane in a batch system. To specify the ability of the isolated fungi, the effect of operating temperature and pollutant concentration on the removal process were studied. The hexane concentration in liquid phase varied in the range of 5-25 mg/L and temperature altered between 25-45 °C in a central composite design analysis. The optimum conditions for hexane biodegradation obtained at 36.5°C and 8.6 mg/L. The kinetic investigations at 25 and 40 °C presented that Haldane, Webb and Yano models could predict the biodegradation well with R2 > 0.98. The kinetic parameters of Haldane model at 40 °C were νmax= 3.57 (mg/gBiomass.h), KS=9.57 mg/L, and KI=20.48 mg/L.