Dynamic analysis of removal and selective oxidation of H2S to elemental sulfur over Cu-V and Cu-V-Mo mixed oxides in a fixed bed reactor

Yasyerli, S
Dogu, G
Ar, I
Doğu, Timur
Selective oxidation of H2S to elemental sulfur was studied using the Cu-V and Cu-V-Mo mixed oxide catalysts with different O-2/H2S ratios between 0 and 3. High activities and high sulfur selectivities reaching 0.98 were obtained with the Cu-V catalyst. The Cu-V-Mo mixed oxide catalyst showed higher activity with a somewhat less selectivity. The Cu-V catalyst, which was originally in the form of alpha-Cu2V2O7, was converted to Cu3VS4, CuS and VOx during the initial stages of reaction. Oxidized form of the catalyst resulted in the formation of mostly SO2. Partially reduced catalyst containing V+2 and V+4 was highly selective for the production of elemental sulfur, which was produced by a series of redox reactions involving lattice oxygen.


Enhancement of biodegradability by continuous ozonation in Acid Red-151 solutions and kinetic modeling
Gokcen, F; Ozbelge, TA (Elsevier BV, 2005-11-15)
In this work, continuous ozonation of aqueous Acid Red-151 was performed in a stirred tank reactor at neutral pH and 25 degrees C. The results show that ozonation is capable of a rapid conversion of the Acid Red-151 dye molecule to more biodegradable intermediates up to the ozonation time of 120 min at which the optimum BOD5/COD ratio is obtained. The peak BOD5/COD ratios were found to be in the range of 0.028-0.35 for the initial dye concentrations being in the range of 1000-100 mg/L, respectively.
Dynamic analysis of adsorption equilibrium and rate parameters of reactants and products in MTBE, ETBE and TAME production
Oktar, N; Murtezaoglu, K; Doğu, Timur; Dogu, G (Wiley, 1999-04-01)
Adsorption equilibrium constants of ethanol, methanol, isobutylene, isoamylenes (2M2B, 2M1B), MTBE and TAME on Amberlyst 15 catalyst were evaluated from the packed bed moment technique. Adsorption equilibrium constants of alcohols were found to be two orders of magnitude greater than the adsorption equilibrium constants of i-olefins and the corresponding tertiary ethers. However, their apparent heat of adsorption values are quite low (-6,7 kJ/mol and -8.3 kJ/mol for methanol and ethanol, respectively). Amon...
Simultaneous production of tert-Amyl ethyl ether and tert-Amyl alcohol from isoamylene-ethanol-water mixtures in a batch-reactive distillation column
Varisli, D; Doğu, Timur (American Chemical Society (ACS), 2005-07-06)
tert-Amyl ethyl ether (TAEE) and tert-amyl alcohol (TAA), which are the attractive alternatives to methyl tert-butyl ether as octane-enhancing gasoline-blending components, are produced by the simultaneous etherification and hydration of 2-methyl-2-butene (2M2B) in a batch-reactive distillation column. It was shown that, by changing the reboiler temperature in the range of 90-124 degrees C, significant increases of the overall fractional conversion of 2M2B, reaching values of 0.99, were achieved in this sys...
Dynamic and steady-state analysis of oxidative dehydrogenation of ethane
Karamullaoğlu, Gülsün; Doğu, Timur; Department of Chemical Engineering (2005)
In this research, oxidative dehydrogenation of ethane to ethylene was studied over Cr-O and Cr-V-O mixed oxide catalysts through steady-state and dynamic experiments. The catalysts were prepared by the complexation method. By XRD, presence of Cr2O3 phase in Cr-O; and the small Cr2O3 and V2O4 phases of Cr-V-O were revealed. In H2-TPR, both catalysts showed reduction behaviour. From XPS the likely presence of Cr+6 on fresh Cr-O was found. On Cr-V-O, the possible reduction of V+5 and Cr+6 forms of the fresh sa...
Dynamic analysis of changes in diffusion and sorption parameters in the reaction of SO2with activated soda ash
Doǧu, Gülsen; Keskin, Alne; Doǧu, Timur (Wiley, 1988-8)
Variations in pore structure cause significant changes in diffusion resistance and adsorption characteristics during the reaction of SO2 with activated soda. Breakthrough and moment analysis of the SO2‐activated soda ash reaction showed that the effective diffusion coefficient of SO2 in the solid product (mostly Na2SO3) was about three times smaller than its value in the original activated soda. About 30% of the diffusion flux of SO2 in the solid product was found to be due to surface diffusion. The adsorpt...
Citation Formats
S. Yasyerli, G. Dogu, I. Ar, and T. Doğu, “Dynamic analysis of removal and selective oxidation of H2S to elemental sulfur over Cu-V and Cu-V-Mo mixed oxides in a fixed bed reactor,” CHEMICAL ENGINEERING SCIENCE, pp. 4001–4009, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62952.