title: Visible light photocatalytic water disinfection and its kinetics using Ag-doped titania nanoparticles.
abstract: The UN estimated about five million deaths every year due to water-borne diseases, accounting from four billion patients. Keeping in view, the ever increasing health issues and to undermine this statistics, a reliable and sustainable water-treatment method has been developed using visible light for water treatment. titania nanoparticles (NPs) have been synthesized successfully by a more applicable method Viz: liquid impregnation (LI) method. The bacterial death rate by photocatalysis under visible light was studied by employing a typical fluorescent source and was found to follow pseudo first-order reaction kinetics. The nanoparticles were characterized using X-ray diffraction (XRD), scanning electron microscopy, and energy-dispersive X-ray spectroscopy to deduce their size range, surface morphology, and elemental compositions, respectively. Among all the prepared grades, 1% Ag-TiO2 was found to be a very effective photocatalytic agent against Escherichia coli. The resulted photoinactivated data were also evaluated by different empirical kinetic models for bacterial inactivation. Hom, Hom-power, Rational, and Selleck models were not able to explain the disinfection kinetics but modified-Hom model fitted best with the experimentally obtained data by producing a shoulder, log-linear, and a tail region.
authors.affiliation: Institute of Environmental Sciences and Engineering, National University of Sciences and Technology, Sector H-12, Islamabad, Pakistan, younasseven@yahoo.com.
authors.forename: Hassan
authors.initials: H
authors.lastname: Younas
authors.forename: Ishtiaq A
authors.initials: IA
authors.lastname: Qazi
authors.forename: Imran
authors.initials: I
authors.lastname: Hashmi
authors.forename: M Ali
authors.initials: MA
authors.lastname: Awan
authors.forename: Asif
authors.initials: A
authors.lastname: Mahmood
authors.forename: Hafiz Adil
authors.initials: HA
authors.lastname: Qayyum
mesh_terms: D002384:Catalysis; D004396:Coloring Agents / Q000737:chemistry; D004203:Disinfection / Q000379:methods*; D006801:Humans; D007700:Kinetics; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D055668:Photochemical Processes; D012834:Silver / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D004396:Coloring Agents; C009495:titanium dioxide; D012834:Silver; D014025:Titanium