Competitive removal of phenol and 2,4-dichlorophenol in biological activated carbon system

Laboratory scale experiments were conducted to evaluate the removal capacit ies of the major competitive components in a biological activated carbon (B AC) system. Adsorption, desorption, biodegradation, biosorption, and bioreg eneration were considered as the major target reactions. Phenol and 2,4-dic hlorophenol were used in a single and bisolute system. The adsorption exper iment showed that 2,4-DCP was a stronger adsorbate than phenol both in sing le and bisolute systems. On desorption of 2,4-DCF, the small fraction of so rbed compounds was reversible but phenol had comparatively high reversibili ty. All solutions exhibited high degrees of irreversible adsorption as hyst eresis. Desorption in background organics showed high reversibility. The bi omass sorptions of phenol and 2,4-DCP were both negligible so that the remo val of these compounds could be disregarded in the BAC system. Meanwhile, t he biodegradation of phenol was higher than that of 2,4-DCP in both as a si ngle and bisolute systems. The biodegradation of phenol was higher than tha t of 2,4-DCP in both single and bisolute systems. Although, the biodegradat ion capability of phenol was suppressed in the presence of 2,4-DCP but it i nduced the biodegradation of 2,4-DCP. In single solute, the degree of biore generation in terms of phenol and 2,4DCP in single solute were 76.28% and 5 6.80%, respectively. In bisolute system, they were 74.46% and 60.20% for ph enol and 2,4-DCP, respectively and degree of bioregeneration was correspond ing to degree of hysteresis.