Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Low temperature photocatalytic oxidation of carbon monoxide over palladium doped titania catalysts
Download
index.pdf
Date
2010
Author
Yetişemiyen, Pelin
Metadata
Show full item record
Item Usage Stats
196
views
68
downloads
Cite This
The room temperature photocatalytic oxidation of carbon monoxide in excess air was examined over silica/titania and 0.1%palladium/silica/titania catalysts under UV irradiation. The experiments were conducted in batch re-circulated reactor with the initial 1000 ppm carbon monoxide in air and 0.5 g catalyst charge and the conversion of carbon monoxide to carbon dioxide was followed by FT-IR spectro-photometer. The change in gas composition in dark and under 36 Watts of UV irradiation exposed to a catalyst area of 12.4 centimeter square indicated both adsorption of carbon monoxide and conversion of carbon monoxide to carbon dioxide over the catalyst samples. The effect of catalyst composition (silica/titania) ratio and the presence of palladium oxide were investigated. The catalyst samples were synthesized by sol-gel technique and all samples were hydrothermally treated before calcination in air. The catalyst samples were characterized by XRD and nitrogen adsorption techniques. XRD results indicated that titania is comprised of pure anatase phase and palladium oxide preferantially dispersed over titania. BET surface area of the samples were observed to increase with silica loading and the BJH results showed isotherms of Type V v with H2 hysteresis loops. The highest carbon monoxide adsorption rate constant was achieved with pure silica with the highest surface area. Photocatalytic activity measurements indicated that carbon monoxide in excess air can be successfully oxidized at room temperature over the titania photocatalyts. Higher physisorption was observed over higher silica containing samples and higher oxidation activity was observed with increasing titania/silica ratio. The optimum titania/silica ratio was determined by the titania content and surface area of catalyst. The activity tests were also indicated that the addition of palladium oxide phase synergistically increased the adsorption and oxidation activity of the catalysts.
Subject Keywords
Chemical engineering.
,
Carbon monoxide.
,
Oxidation.
,
Catalysis.
URI
http://etd.lib.metu.edu.tr/upload/12612466/index.pdf
https://hdl.handle.net/11511/20110
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
Carbon monoxide oxidation under oxidizing and reducing conditions with alkali-metal and palladium doped tin dioxide
Mirkelamoğlu, Burcu; Karakaş, Gürkan; Department of Chemical Engineering (2006)
The investigation of CO oxidation with supported noble metal catalysts to develop a fundamental understanding of the nature of the active sites, adsorbate-surface interactions, surface reaction pathways and the role of promoters is of prime importance for development of highly active and selective catalyst formulations for low temperature oxidation of carbon monoxide. Low temperature CO oxidation catalysts find applications in monitoring and elimination of CO in chemical process exhaust gases, in on-board c...
Room Temperature Photocatalytic Oxidation of Carbon Monoxide Over Pd/TiO2-SiO2 Catalysts
Karakaş, Gürkan (Springer Science and Business Media LLC, 2013-12-01)
The photocatalytic oxidation of carbon monoxide over TiO2-SiO2 and Pd/TiO2-SiO2 catalysts was studied. The catalyst samples were synthesized by using sol-gel technique coupled with hydrothermal treatment and all samples were hydrothermally treated before calcination in air. The catalyst samples were characterized by XRD, BET and DRIFTS techniques. The photocatalytic activity of the samples was determined by using circulated batch photoreactor coupled with in line gas transmission FTIR cell charged with 2,00...
Low temperature synthesis of SAPO-34 in a recirculating-flow system
Topuz, Berna; Oral, Eda E.; Kalıpçılar, Halil (2013-12-01)
SAPO-34 was synthesized both in recirculating-flow system and in autoclaves at low temperatures. A two-stage, varying temperature synthesis procedure was applied to reduce the crystallization time. The effects of synthesis temperature and synthesis system on the purity, particle size and BET surface area of the crystalline phase were examined. Pure SAPO-34 with high crystallinity was synthesized from a gel with Si/Al ratio of 0.2 at 130 A degrees C following aging at 80 A degrees C. The particle sizes of SA...
Application of semi conductor films over glass/ceramic surfaces and their low temperature photocatalytic activity
Ersöz, Tuğçe İrfan; Karakaş, Gürkan; Department of Chemical Engineering (2009)
Semiconductor metal oxides can be induced by light with proper wavelength resulting in oxidation and reduction reactions for the transformation of water and oxygen molecules into active radicals. With this method, it is possible to obtain self-cleaning surfaces and products having antimicrobial properties. The aim of this study is to develop semiconductor metal oxide thin films for multifunctional glass products and the characterization of photocatalytic self cleaning and antimicrobial properties. As semico...
Low temperature plasma as a means to transform nanoparticle atomic structure
Üner, Necip Berker; Thimsen, E. (2018-07-01)
Low temperature plasma (LTP) is a highly nonequilibrium substance capable of increasing the specific free energy of mass that flows through it. Despite this attractive feature, there are few examples of the transformation of solid material with an equilibrium atomic structure into a material with a nonequilibrium atomic structure. As a proposed example of such a transformation, in this work, it is argued that the transformation of crystalline metal nanoparticles into amorphous metal nanoparticles is feasibl...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
P. Yetişemiyen, “Low temperature photocatalytic oxidation of carbon monoxide over palladium doped titania catalysts,” M.S. - Master of Science, Middle East Technical University, 2010.