Reductive degradation of oxygenated polycyclic aromatic hydrocarbons using an activated magnesium/co-solvent system

This study evaluates the capability of zero-valent magnesium and a protic co-solvent to promote the degradation of oxygenated polycyclic aromatic hydrocarbons compounds, specifically 9-fluorenone, 9,10-anthraquinone, 7,12-benz(a)anthraquionone, and 7H-benz(de)anthracene-7-one. At room temperature conditions, greater than 86% degradation efficiency is observed after 24 h of reaction time for a mixture containing 0.05 g of magnesium and four selected oxygenated aromatic hydrocarbons with 250 mg L−1 concentrations. It is noted that glacial acetic acid is needed as an activator for the degradation reaction to proceed. It is also presumed that the acid removes oxide and hydroxide species from the magnesium surface. With the GC–MS analysis of the reaction products, possible reductive pathways are suggested. Furthermore, this study is the first report on the degradation of these emerging contaminants and it is proposed that the magnesium-powder/protic-solvent system is a promising low-cost reagent and may allow for the future development of an economic and environmentally-friendly remediation application.

► The use of Mg–cosolvent system for the simultaneous degradation of OPAHs at room temperature.
► Reductive degradation of the selected OPAHs occurred, after the activation of Mg with acetic acid.
► This system degraded the selected OPAHs (>86%) and produced several derivatives within 24 h.
► Degradation products may be less toxic than OPAHs.
► This is the first report on OPAH remediation and may lead to the development of an actual field application.