title: Removal of micropollutants and NOM in carbon nanotube-UF membrane system from seawater.
abstract: One of the main problems for seawater reverse osmosis desalination is membrane fouling associated with natural organic matter. Bisphenol-A (BPA) and 17alpha-ethinylestradiol (EE2) are well-known endocrine-disrupting compounds that have been detected in wastewater and seawater. In this study, the contribution of carbon nanotubes (CNTs, single-walled carbon nanotubes) to membrane fouling control and the potential adsorption mechanisms of BPA and EE2 were investigated using artificial seawater (ASW) in a bench scale ultrafiltration (UF) membrane coupled with CNTs. For high ionic strength ASW, UVA254 nm is a good alternative for highly aromatic dissolved organic carbon (DOC) determination, with a very strong linear relationship (R2 > or = 0.99) with increasing DOC concentrations. Approximately 80% of DOC in ASW was rejected by the CNT-UF system where 31% of DOC was removed due to adsorption by CNTs. The presence of CNTs shows a 20% increase in membrane flux in ASW. A strong linear correlation between retention and adsorption of BPA and EE2 was obtained. The percentage of adsorption/retention of BPA and EE2 in UF-CNTs follows the order: 94.0/96.6 (DI + CNTs, EE2) > 86.2/90.0 (ASW + CNTs, EE2) > 73.6/78.9 (DI + CNTS, BPA) > or = 74.1/77.3 (ASW + CNTS, BPA) > 29.8/29.8 (ASW, EE2) approximately equal to 27.3/27.3 (ASW, BPA) > or = 25.3/25.3 (DI, EE2) approximately equal to 24.8/24.8 (DI, BPA). This indicates that retention by the UF-CNT system is mainly due to adsorption. Overall, EE2 adsorption was greater than BPA during the UF-CNT experiments, presumably due to the higher hydrophobicity of EE2 than BPA.
authors: Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA.
authors: Jiyong
authors: J
authors: Heo
authors: Lesley
authors: L
authors: Joseph
authors: Yeomin
authors: Y
authors: Yoon
authors: Yong-Gyun
authors: YG
authors: Park
authors: Namguk
authors: N
authors: Her
authors: Jinsik
authors: J
authors: Sohn
authors: Seong-Hoon
authors: SH
authors: Yoon
mesh_terms: D000327:Adsorption; D001559:Benzhydryl Compounds; D004997:Ethinyl Estradiol / Q000737:chemistry; D008567:Membranes, Artificial; D009995:Osmosis; D010636:Phenols / Q000737:chemistry; D012623:Seawater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004997:Ethinyl Estradiol; D008567:Membranes, Artificial; D010636:Phenols; D014874:Water Pollutants, Chemical; C006780:bisphenol A; D000098826:Bisphenol A Compounds