title: An adsorption-photocatalysis hybrid process using multi-functional-nanoporous materials for wastewater reclamation.
abstract: In this study, two of our recently developed laboratory scale wastewater treatment systems, fluidized-bed reactor (FBR) using formulated clay mixture absorbents (clay-FBR adsorption) and an annular slurry photoreactor (ASP) using TiO(2) impregnated kaolin catalysts (TiO(2)-K-ASP) were integrated as an adsorption-photocatalysis hybrid process to treat municipal wastewater as alternative secondary and tertiary treatment for wastewater reclamation. Primary effluent from sewage and secondary effluent from a membrane bioreactor treatment process were used to assess chemical removal capabilities of the FBR and ASP systems, and the hybrid process. The formulated clays-FBR system demonstrated the prevailing removal efficiency toward PO(4)(3-), NO(3)(-) and suspended solids. The TiO(2)-K-ASP showed superior degradation of dissolved organic content; while the presence of inorganic ions caused a detrimental effect on its performance. The integration of the adsorption and degradation system as a hybrid treatment process resulted in a synergetic enhancement for the chemical removal efficiency. Complete elimination of PO(4)(3-) content was obtained in the adsorption stage; while 30% and 65% NO(3)(-) removal were obtained from the hybrid treatment of the primary and secondary effluents, respectively. The corresponding COD reduction during the photodegradation was further investigated by the high-performance size exclusion chromatography technique, where it revealed the shift of apparent molecular weight of the dissolved organic contaminants toward the smaller region. This present study demonstrated that this adsorption-photocatalysis hybrid technology can be used as a feasible alternative treatment process for wastewater reclamation.
authors.affiliation: School of Chemical Engineering, The University of Adelaide, Adelaide, SA 5005, Australia.
authors.forename: Vipasiri
authors.initials: V
authors.lastname: Vimonses
authors.forename: Bo
authors.initials: B
authors.lastname: Jin
authors.forename: Christopher W K
authors.initials: CW
authors.lastname: Chow
authors.forename: Christopher
authors.initials: C
authors.lastname: Saint
mesh_terms: D000327:Adsorption; D019149:Bioreactors; D002384:Catalysis; D002850:Chromatography, Gel; D006863:Hydrogen-Ion Concentration; D007616:Kaolin / Q000737:chemistry; D008027:Light; D058608:Nanopores; D009930:Organic Chemicals / Q000302:isolation & purification; D010100:Oxygen / Q000032:analysis; D059027:Recycling; D012995:Solubility; D014025:Titanium / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
chemical_list: D009930:Organic Chemicals; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D007616:Kaolin; D014025:Titanium; D010100:Oxygen