Sensitization of semiconducting powder catalysts in water purification: Photodegradation of medical drugs and microorganisms

Thumbnail Image
Date
2011-06-01
Authors
Fedaa Salih
Ahed Zyoud
Majdi Dweikat
Hikmat S. Hilal
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
<p>Photocatalytic degredation of organic contaminants in water and air attracts great deal ofattention. TiO2 is the most widely used semiconductor photocatalyst due to its high photostability,low cost, non-toxic nature, high oxidizing potential and its water insolubility underdifferent conditions. In this work TiO2 was prepared from TiCl3 then sensitized byanthocyanin natural dye extracted from Hibiscus (Karkade). The TiO2/anthocyanin systemwas then used as a catalyst to photo-degraded phenazopyridine and E-colli bacteria in water.Catalytic experiments were conducted in a 100 mL magnetically stirred thermostatedbeaker. The out-side walls of the beaker were covered withaluminum foil. Direct visible irradiation using a solar simulator halogenspot lamp (1300 Lux, 0.0001898W/cm2) was applied vertically to the photo-catalytic mixturesurface. The contaminant concentration was measured every 25 minute by polarography.TiO2 was characterized by measuring the XRD, SEM, photoluminescence, UV-visible spectra.Different parameters were studied, such as pH, contaminant concentration, catalystconcentration and temperature. The efficiency of the catalyst increased with increasing thecontaminant concentration, catalyst concentration and pH value. Photodegradtion reactionrate was temperature independent. Results and discussions will be presented together withpossible mechanisms.</p>
<p>Photocatalytic degredation of organic contaminants in water and air attracts great deal ofattention. TiO2 is the most widely used semiconductor photocatalyst due to its high photostability,low cost, non-toxic nature, high oxidizing potential and its water insolubility underdifferent conditions. In this work TiO2 was prepared from TiCl3 then sensitized byanthocyanin natural dye extracted from Hibiscus (Karkade). The TiO2/anthocyanin systemwas then used as a catalyst to photo-degraded phenazopyridine and E-colli bacteria in water.Catalytic experiments were conducted in a 100 mL magnetically stirred thermostatedbeaker. The out-side walls of the beaker were covered withaluminum foil. Direct visible irradiation using a solar simulator halogenspot lamp (1300 Lux, 0.0001898W/cm2) was applied vertically to the photo-catalytic mixturesurface. The contaminant concentration was measured every 25 minute by polarography.TiO2 was characterized by measuring the XRD, SEM, photoluminescence, UV-visible spectra.Different parameters were studied, such as pH, contaminant concentration, catalystconcentration and temperature. The efficiency of the catalyst increased with increasing thecontaminant concentration, catalyst concentration and pH value. Photodegradtion reactionrate was temperature independent. Results and discussions will be presented together withpossible mechanisms.</p>
Description
Keywords
Citation