title: Removal of pharmaceuticals from MWTP effluent by nanofiltration and solar photo-Fenton using two different iron complexes at neutral pH.
abstract: In recent years, membrane technologies (nanofiltration (NF)/reverse osmosis (RO)) have received much attention for micropollutant separation from Municipal Wastewater Treatment Plant (MWTP) effluents. Practically all micropollutants are retained in the concentrate stream, which must be treated. Advanced Oxidation Processes (AOPs) have been demonstrated to be a good option for the removal of microcontaminants from water systems. However, these processes are expensive, and therefore, are usually combined with other techniques (such as membrane systems) in an attempt at cost reduction. One of the main costs in solar photo-Fenton comes from reagent consumption, mainly hydrogen peroxide and chemicals for pH adjustment. Thus, in this study, solar photo-Fenton was used to treat a real MWTP effluent with low initial iron (less than 0.2 mM) and hydrogen peroxide (less than 2 mM) concentrations. In order to work at neutral pH, iron complexing agents (EDDS and citrate) were used in the two cases studied: direct treatment of the MWTP effluent and treatment of the concentrate stream generated by NF. The degradation of five pharmaceuticals (carbamazepine, flumequine, ibuprofen, ofloxacin and sulfamethoxazole) spiked in the effluent at low initial concentrations (μg L(-1)) was monitored as the main variable in the pilot-plant-scale photo-Fenton experiments. In both effluents, pharmaceuticals were efficiently removed (>90%), requiring low accumulated solar energy (2 kJUV L(-1), key parameter in scaling up the CPC photoreactor) and low iron and hydrogen peroxide concentrations (reagent costs, 0.1 and 1.5 mM, respectively). NF provided a clean effluent, and the concentrate was positively treated by solar photo-Fenton with no significant differences between the direct MWTP effluent and NF concentrate treatments.
authors.affiliation: Plataforma Solar de Almería-CIEMAT. Carretera Senés km 4, 04200 Tabernas (Almería), Spain.
authors.forename: S
authors.initials: S
authors.lastname: Miralles-Cuevas
authors.affiliation: Plataforma Solar de Almería-CIEMAT. Carretera Senés km 4, 04200 Tabernas (Almería), Spain.
authors.forename: I
authors.initials: I
authors.lastname: Oller
authors.affiliation: Departamento de Ingeniería Química de la Universidad de Almería. Carretera Sacramento S/N, 04120 Almería, Spain.
authors.forename: J A Sánchez
authors.initials: JAS
authors.lastname: Pérez
authors.affiliation: Plataforma Solar de Almería-CIEMAT. Carretera Senés km 4, 04200 Tabernas (Almería), Spain. Electronic address: sixto.malato@psa.es.
authors.forename: S
authors.initials: S
authors.lastname: Malato
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000737:chemistry* / Q000528:radiation effects; D013472:Sunlight; D014462:Ultrafiltration; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects; D018508:Water Purification / Q000379:methods*
chemical_list: D056831:Coordination Complexes; C045076:Fenton's reagent; D004364:Pharmaceutical Preparations; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron
keywords: Compound parabolic collectors; Iron complexes; Micropollutants; Nanofiltration; Photo-Fenton; Solar photocatalysis