Thesis Type: Postgraduate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2019
Student: TUNAHAN UÇAR
Supervisor: NAİL YAŞYERLİ
Open Archive Collection: AVESIS Open Access Collection
Abstract:In this study, alumina-supported Ag and Fe-Ag catalysts were prepared and tested in the reaction system for selective catalytic oxidation reaction of H2S. Alumina which was prepared by two different sol-gel methods (SG1, SG2) was used as a catalyst support material. Catalysts were also synthesized using commercial alumina to determine the effect of the support material on catalytic activity. 10% by weight of Ag and Fe were loaded on the alumina by wet impregnation method. Structural properties of catalysts were determined by using different characterization techniques (N2 adsorption-desorption, XRD, SEM, EDS). N2 adsorption-desorption analysis showed that Ag catalysts impregnated onto alumina support materials synthesized by sol-gel method had uniform mesoporous structure. XRD analysis of catalysts showed that the crystalline structure of Ag catalysts generally consisted of metallic Ag and γ-Al2O3, and Ag-Fe catalysts consisted of metallic Ag, Fe2O3 and γ-Al2O3. Catalytic activities of synthesized catalysts were investigated at 2500C temperature and different feed gas compositions (O2/H2S:0,5 and 1,0) in the packed-column reaction test system. Ag/Al2O3 catalysts which were the support materials were prepared by sol-gel methods showed higher activity than Ag catalyst which had commercial support. Iron addition to the structure increased the activity of all Ag/Al2O3 catalysts and 100% H2S conversion was achieved with Fe@Ag/Al2O3-SG1 and Fe@Ag/Al2O3-SG2 catalysts. 100% sulfur selectivity was achieved with Ag/Al2O3 catalysts. A small decrease in the selectivity was observed with the iron addition to the catalyst structure. The increase in oxygen content in the feed stream caused a decrease in sulfur selectivity