Investigating the role of surfactants in the mechanochemical remediation of persistent organic pollutants

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants that are environmentally persistent. Remediation of PAHs has been the focus of many studies due to their toxic and carcinogenic properties that pose a serious threat to human health. There are several remediation techniques for the removal of PAHs in the soil including bioremediation, and soil washing. Although these technologies are currently applied, there are challenges with their applications in the context of PAHs. Bioremediation is limited to biodegradable pollutants; products of bioremediation can be more harmful than the starting pollutants and it is hard to implement on a large-scale. Similarly, soil washing is not sustainable for the environment since excessive concentrations of flammable solvents or enhancing agents are required to achieve moderate extraction yields. In this thesis, we successfully pioneered a new mechanochemical remediation technique: surfactant-liquid assisted grinding (SURFLAG) for the efficient extraction of PAHs. We tested the dispersing effect of surfactants to aid in the chemical oxidation reactions of pyrene (PYR) in the presence of a metal catalyst, principally magnetite. It was evident that PYR was dispersed onto the magnetite surface by the aid of the surfactant. We studied the application of surfactant to support the environmental remediation of pollutants from the soil. Moreover, we compared the pollutant extraction efficiency the novel remediation technique SURFLAG with the common traditional remediation technique surfactant-assisted soil washing (SAW).

Date of Award	Dec 2021
Original language	American English