Brunel University London, UK
Title: Unravelling the chemistry behind the toxic effects of refining wastewater: Characterization and remediation
Biography: Angela Pinzon-Espinosa
Refining transforms crude oil into marketable products with high commercial value, providing a third of the global energy requirements and numerous raw materials. The process, however, emits vast amounts of wastewater that can have harmful effects on wildlife and human health but the link between chemistry and observed toxicity is fragile because little progress has been made in determining causative agents. Consequently, current treatment technologies are not targeting key toxicants nor providing safe effluents. Here we show that naphthenic acids are important components of refining wastewater, resulting from the processing of heavy crude oil, and that they have an important contribution to the toxic effects exerted by these effluents. Furthermore, we found that their chemical stability makes them highly resistant to remediation using bacteria and Fe-TAML/H2O2 systems under laboratory conditions, and only sequential aliquots of Fe-TAML catalysts and H2O2 showed to degrade naphthenic acids (50 ppm) within 72 hours. We anticipate our results to be a starting point for better environmental regulations relevant to refining wastewater resulting from heavy crude oil, as naphthenic acids are not currently considered in the effluent guidelines for the refining sector. Furthermore, the degradation of naphthenic acids under mild conditions using Fe-TAML/H2O2 systems indicates that these catalysts hold promise for the remediation of refining wastewater in real-life scenarios.