Photonic crystals in biology - NanoTR-VI

PPP MP MPoster Session, Thursday, June 17Theme F686 - N1123Investigatons on Solar Degradation of Acid Orange 7 (C.I. 15510) In Textile Waste Water With MicroAnd Nano Sized Titan Dioxide11,2USongül Karaaslan AksuUP P* and eref GüçerP1,21PDepartment of Chemistry, Faculty of Science & Arts, Uluda University, Bursa 16059 , TurkeyPBUTAL - Bursa Test and Analysis Laboratory, The Scientific and Technological Research Council of Turkey, Bursa 16190, TurkeyAbstract- Solar photo degradation of dyes is not effective in a treatment of textile waste water. Catalytic activation is necassery in order tohave suitible kinetics. Titan dioxide is seem to be effective for dye degradation. Changing the size of catalyst and dopped with other metals (suchas Sn IV) its activity might be improved . Our results shown that solar degradation of studied dye is posiple in a hour radiations.Textile waste water treatment nowadays is stillenvironmental problem. Azo dyes represent the largest classof textile dyes in industrial use, accounting for 50% of allcommercial dyes [1]. Due to the large number of aromaticspresent in these molecules and the stability of dyes, most azodyes are non-biodegradable [2] and conventional treatmentmethods are ineffective for decolorization and degradation.Physical methods such as adsorption, biological methods(biodegradation) and chemical methods such as chlorinationand ozonation are the most frequently used methods forremoval of the textile dyes from wastewater. Others areflocculation, reverse osmosis and adsorption onto activatedcarbon. Since they are not destructive but only transfer thecontamination from one phase to another, a different kind ofpollution is faced and further treatments are required. Namely,advanced oxidation processes have been extensivelyinvestigated [3]. Among these processes, heterogeneousphotocatalysis is found as an emerging destructive technologyleading to total mineralization of most of organic pollutants. Inmost cases, the degradation is conducted for dissolvedcompounds in water with UV-illuminated TiOR2R. Amongvarious semiconducting materials most attention has beengiven to TiOR2R because of its high photocatalytic activity,resistance to photo-corrosion, low cost, non-toxicity andfavorable band-gap energy. That is why TiOR2R has realadvantage in the photo-catalytic activity [4–5]. A furtherimportant advantage is the fact that the process can bepowered by natural sunlight [6–8], thus reducing significantlythe electrical power requirements and operating costs. Itshould be noted that with visible light, the photo-degradationprocesses proceed by different routes, involving for exampleelectron transfer from the excited state of the dye moleculesadsorbed on the TiOR2R surface into the conduction band ofTiOR2R.The aim of this study is to investigate the photo catalyticactivities of Acid Orange 7 (AO 7) dye which is frequentlyused in textile industry. The rate constant of photo catalyticreactions were determined by using simulation of solar lightand titanium dioxide as a catalyst . The dye content wasdetermined by using VIS spectrometry with the wavelength ofAO7: 485 nm and with using derivative spectroscopy. Inkinetic studies, the most important parameters which effect theobservations were matrix of dye solutions, light intensity andthe structure of catalyst. Relevant kinetic data are summarizedTable 2.Table 1. Summary of rate constants for the degradation of solutionsSample k t R1/2R (min)-55,71x 10P AO 7 0,00012 1,50E+08Textile waste water 0,00010 1,75E+08-55,71x 10P O7 +0,02 g TiOR2R 0,0147 47Textile waste water+0,02 g TiOR2R 0,00010 1,75E+08Textile waste water+0,02 g (Ti,Sn)OR2R 0,008 87Using FTIR spectroscopic data, it was shown that dye islinked to three Titanium surface metallic cations through twooxygen atoms from the sulfonate group and the oxygen atomof the carbonyl group of the dyes (Fig 1).Figure 1. Proposed adsorption mode of AO7 on the surfaceScanning electron microscopy (SEM) was employed thecharacterized surface morphology of the catalyst. It can beseen from Fig. 2Figure 2. SEM images of AO7- TiOR2It was shown that decomposition was completed in a hour.*Corresponding author: songulkar@yahoo.com[1] C. Rafols, D. Barcelo. Journal of Chromatography A, 777 177-192 (1997)[2] S. Liakou, S. Pavlou, G. Lyberatos, Water Sci. Technol. 35 (4)279–286 1997) .[3] C. Guillard, H. Lachheb, A. Houas, M. Ksibi, E. Elaloui, J.M.Herrmann, J. Photochem. Photobiol. A: Chem. 158 27–36 (2003).[4] K. Nagaveni, G. Sivalingam, M.S. Hegde, G. Madras, Appl.Catal. B: Env. 48 83–93 (2004) .[5] C.E. Bonancea, G.M. Nascimento, M.L. Souza, M.L. A.Temperini, C.Paola, Appl. Catal. B: Env. 69 34–42(2006) .[6] M. Saquib, M. Muneer , Dyes Pigments;53: 237-49 (2002).[7] V. Augugliaro, C. Baiocchi, A.B. Prevot, E. Garc´a-Lopez, V.Loddo, S. Malato, et al. Chemosphere;49.1223–30 (2002).[8] M. Stylidi, DI Kondarides, XE Verykios, Appl Catal B Environ40:271-86 (2003).6th Nanoscience and Nanotechnology Conference, zmir, 2010 799