Sewage Sludge Polycyclic Aromatic Hydrocarbon (PAH) Decontamination Technique Based on the Utilization of a...

A decontamination technique based on the utilization of a lipopeptide biosurfactant extracted from corn steep liquor has been developed to eliminate polycyclic aromatic hydrocarbons (PAHs) from sewage sludge. High concentrations of PAHs were used during experiments observing that 408.3 mg/kg of naphthalene was almost completely mobilized and biodegraded, only 1.7% of naphthalene remained in the sewage sludge, whereas anthracene and pyrene were reduced up to 51.7 and 69.4%, respectively. The biodegradation of PAHs was fitted to several kinetic models (zero- and first-order kinetic models), observing good correlation coefficient values when biodegradation was described by the first-order kinetic model. Experimental results suggest that biosurfactant extracted from corn steep liquor may have great potential, as an ecofriendly washing agent, for the treatment of sewage sludge contaminated with PAHs. Therefore, in situ application of natural biosurfactants may be considered to be a good remediation alternative as they are not hazardous for water and soil organisms.