Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) by Laccase in Rhamnolipid Reversed Micellar System

Rhamnolipid was applied to degrade anthracene and pyrene in reversed micelles. The parameters in degradation were optimized for the purpose of improving degradation rates. The proper amount of rhamnolipid (RL) used for degrading anthracene was 0.065 mM, while 0.075 mM for pyrene. However, reaction time for degrading both anthracene and pyrene was 48 h. The optimum water content, pH, laccase concentration, polycyclic aromatic hydrocarbon (PAH) initial concentration, and volume ratio of n-hexanol to isooctane for both were found out. The highest degradation rates of anthracene and pyrene were 37.52 and 25.58 %, respectively. Although the degradation rates were not higher than the results previous literatures reported, this method was of novelty and provided guidance in application in degrading PAHs by reversed micellar system, especially for biosurfactant-based reversed micelles.