title: Degradations of acetaminophen via a K2S2O8-doped TiO2 photocatalyst under visible light irradiation.
abstract: Acetaminophen (ACT) is a mild analgesic commonly used for relief of fever, headache and some minor pains. It had been detected in both fixed factory-discharged wastewaters, and diverse sources, e.g. surface waters during festival events. Degradation of such trace emergent pollutants by titanium dioxide (TiO2) photocatalysts is a common approach; however, the band gap that can be utilized in the UV range is limited. In order to extend downward the energy required to excite the photocatalytic material, doping with potassium peroxodisulfate (K2S2O8) by a sol-gel method was done in this work. The visible-light active photocatalyst was tested on the degradation of ACT under four parameters including: initial ACT concentration, catalyst dose, initial pH, and system temperature. Optimal conditions, which achieved 100% ACT degradation, were obtained by using 0.1 mM ACT initial concentration, catalyst dose of 1 g L(-1), initial pH of 9.0 and system temperature of 22 °C at the end of 9-h irradiation. Meanwhile, three types of degradation kinetic models (i.e. zero, pseudo first and second order) were tested. The feasible model followed a pseudo-first order model with the computed constant (kapp) of 7.29 × 10(-3) min(-1). The present study provides a better photocatalytic degradation route by K2S2O8-modified TiO2 in comparison with pristine TiO2, in wastewater treatment dealing with ACT and other persistent organic pollutants.
authors.affiliation: Department of Environmental Engineering and Science, Feng Chia University, Taichung 407, Taiwan.
authors.forename: Justin Chun-Te
authors.initials: JC
authors.lastname: Lin
authors.affiliation: Department of Chemical Engineering, University of the Philippines Diliman, Quezon City 1101, Philippines.
authors.forename: Mark Daniel G
authors.initials: MDG
authors.lastname: de Luna
authors.affiliation: Department of Chemical Engineering, University of the Philippines Diliman, Quezon City 1101, Philippines.
authors.forename: Graziel L
authors.initials: GL
authors.lastname: Aranzamendez
authors.affiliation: Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan 717, Taiwan. Electronic address: mmclu@mail.cnu.edu.tw.
authors.forename: Ming-Chun
authors.initials: MC
authors.lastname: Lu
mesh_terms: D000082:Acetaminophen / Q000032:analysis / Q000737:chemistry*; D002384:Catalysis; D007700:Kinetics; D008027:Light; D010782:Photolysis; D017680:Potassium Compounds / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D017680:Potassium Compounds; D013431:Sulfates; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D000082:Acetaminophen; C009007:potassium persulfate; D014025:Titanium
keywords: Acetaminophen; Doping; Photocatalytic degradation parameters; Potassium persulfate; TiO(2); Visible light active catalyst