Effect of rhamnolipid biosurfactant on the degradation of pentaerythritoltetranitrate (PETN)

Abstract

This study investigated the bioremediation of explosive pentaerythritoltetranitrate (PETN) in presence of rhamnolipid (RL) biosurfactant by aerobic process. Microbial inoculate were obtained from a textile wastewater treatment plant activated sludge. Addition of rhamnolipid surfactant (60 mg/l) increased the removal efficiency of PETN from 33 to 76 and COD removal from 20 to 58. Application of rhamnolipid led to mineralization of PETN. Degradation of PETN is expressed to be of first-order and the kinetic reaction parameters are calculated based on different initial concentrations of PETN. The first-order rate constant of the rhamnolipid amended experiments were at least 3.6 orders of magnitude higher for PETN than those found for not amended rhamnolipid experiments. Inoculated bacteria have capability to use of PETN as source of nitrogen and energy. It seems that the addition of rhamnolipid showed great potential for treatment of explosives by textile activated sludge.