title: Mechanistic investigation of industrial wastewater naphthenic acids removal using granular activated carbon (GAC) biofilm based processes.
abstract: Naphthenic acids (NAs) found in oil sands process-affected waters (OSPW) have known environmental toxicity and are resistant to conventional wastewater treatments. The granular activated carbon (GAC) biofilm treatment process has been shown to effectively treat OSPW NAs via combined adsorption/biodegradation processes despite the lack of research investigating their individual contributions. Presently, the NAs removals due to the individual processes of adsorption and biodegradation in OSPW bioreactors were determined using sodium azide to inhibit biodegradation. For raw OSPW, after 28 days biodegradation and adsorption contributed 14% and 63% of NA removal, respectively. For ozonated OSPW, biodegradation removed 18% of NAs while adsorption reduced NAs by 73%. Microbial community 454-pyrosequencing of bioreactor matrices indicated the importance of biodegradation given the diverse carbon degrading families including Acidobacteriaceae, Ectothiorhodospiraceae, and Comamonadaceae. Overall, results highlight the ability to determine specific processes of NAs removals in the combined treatment process in the presence of diverse bacteria metabolic groups found in GAC bioreactors.
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada; Department of Chemical Engineering, Bangladesh University of Engineering and Technology, Dhaka 1000, Bangladesh.
authors.forename: Md Shahinoor
authors.initials: MS
authors.lastname: Islam
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada; Department of Civil and Geological Engineering, College of Engineering, University of Saskatchewan, Saskatoon S7N 5A9, Canada.
authors.forename: Kerry N
authors.initials: KN
authors.lastname: McPhedran
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: yang.liu@ualberta.ca.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: mgamalel-din@ualberta.ca.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Gamal El-Din
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms; D002264:Carboxylic Acids / Q000032:analysis*; D002606:Charcoal / Q000737:chemistry; D061329:Oil and Gas Fields; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002264:Carboxylic Acids; D002606:Charcoal; D062065:Wastewater; D014874:Water Pollutants, Chemical; C046170:naphthenic acid
keywords: Adsorption; Biodegradation; Biofilm; Oil sands process-affected water; Ozonation