Aerobic biodegradation of dinitrophenols and their mixture in continuous operations by an immobilized mixed microbial community
Abstract
Aerobic biodegradation of 2,4-dinitrophenol (2,4-DNP) and 2,6-DNP by an immobilized mixed microbial community in packed-bed reactors was compared for individual components and in a mixture. The reactors efficiently ([ 97 %) removed higher 2,4-DNP concentrations (up to 43 g m- 3) compared to 2,6-DNP (\ 80 % only, even when below 5 g m- 3), the former being metabolized with higher degradation rates.
Similar loadings of both DNPs were efficiently degraded ([ 95 %) when treated as a mixture; i.e., the 2,6-DNP removal efficiency was positively affected by the presence of 2,4-DNP when low concentrations of both pollutants were treated. However, an increase of the total DNP concentration to 41 g m- 3 led to a sizable drop of the degradation rate in the mixture but not when the substrates were treated separately.