Quantifying the roles of thermal volatilization and decomposition in microwave remediation of polycyclic aromatic hydrocarbon–polluted soil and modeling remediation effectiveness

Microwave irradiation is a promising technology for the remediation of soil contaminated by organic contaminants . However, the roles of volatilization and decomposition in microwave removal of polycyclic aromatic hydrocarbons (PAHs) in soil have not yet been quantitatively determined. A model describing the removal efficiency of benz(a)anthracene (BaA) at different treatment times and varied conditions was constructed, wherein BaA removal efficiency was positively and linearly correlated with soil temperature . BaA removal in soil was attributed to thermal volatilization (97.8%) and decomposition (2.2%). Radicals such as ∙OH and ∙O 2 − were found to initiate BaA decomposition, the pathway of which was elucidated through HPLC-MS analysis, revealing benz(a)anthracene-7,12-dione as the main intermediate product. The new ideas and perspectives founded in this study offer theoretical support for microwave remediation of organic compound–contaminated sites.