title: The impact of metallic coagulants on the removal of organic compounds from oil sands process-affected water.
abstract: Coagulation/flocculation (CF) by use of alum and cationic polymer polyDADMAC, was performed as a pretreatment for remediation of oil sands process-affected water (OSPW). Various factors were investigated and the process was optimized to improve efficiency of removal of organic carbon and turbidity. Destabilization of the particles occurred through charge neutralization by adsorption of hydroxide precipitates. Scanning electron microscope images revealed that the resultant flocs were compact. The CF process significantly reduced concentrations of naphthenic acids (NAs) and oxidized NAs by 37 and 86%, respectively, demonstrating the applicability of CF pretreatment to remove a persistent and toxic organic fraction from OSPW. Concentrations of vanadium and barium were decreased by 67-78% and 42-63%, respectively. Analysis of surface functional groups on flocs also confirmed the removal of the NAs compounds. Flocculation with cationic polymer compared to alum, caused toxicity toward the benthic invertebrate, Chironoums dilutus, thus application of the polymer should be limited.
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta , Edmonton, Alberta, Canada, T6G 2W2.
authors.forename: Parastoo
authors.initials: P
authors.lastname: Pourrezaei
authors.forename: Przemysław
authors.initials: P
authors.lastname: Drzewicz
authors.forename: Yingnan
authors.initials: Y
authors.lastname: Wang
authors.forename: Mohamed
authors.initials: M
authors.lastname: Gamal El-Din
authors.forename: Leonidas A
authors.initials: LA
authors.lastname: Perez-Estrada
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Martin
authors.forename: Julie
authors.initials: J
authors.lastname: Anderson
authors.forename: Steve
authors.initials: S
authors.lastname: Wiseman
authors.forename: Karsten
authors.initials: K
authors.lastname: Liber
authors.forename: John P
authors.initials: JP
authors.lastname: Giesy
mesh_terms: D000534:Alum Compounds / Q000737:chemistry; D000818:Animals; D002264:Carboxylic Acids / Q000302:isolation & purification; D002412:Cations; D002683:Chironomidae / Q000187:drug effects; D005427:Flocculation / Q000187:drug effects; D008670:Metals / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D009391:Nephelometry and Turbidimetry; D009821:Oils / Q000737:chemistry*; D009930:Organic Chemicals / Q000302:isolation & purification*; D011108:Polymers / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D014131:Trace Elements / Q000302:isolation & purification; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000633:toxicity; D014876:Water Pollution / Q000032:analysis*
chemical_list: D000534:Alum Compounds; D002264:Carboxylic Acids; D002412:Cations; D008670:Metals; D009821:Oils; D009930:Organic Chemicals; D011108:Polymers; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D014867:Water; D012822:Silicon Dioxide; C046170:naphthenic acid