Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 4Citation - Scopus: 4Adsorption Kinetics of Methane Reformer Off-Gases on Aluminum Based Metal-Organic Framework(Elsevier Ltd., 2020) Angı, Deniz; Çakıcıoğlu Özkan, Seher FehimeSolvothermal synthesis of aluminum based metal-organic frameworks (MIL-53(Al)s) were conducted by considering the effects of crystallization and activation temperatures, and the solvent at purification step. Adsorption kinetics of Steam Methane Reformer off gas components at 34, 70 and 100 °C temperatures was measured by using ZLC method. Henry constant decreases as diffusion coefficient of the gases increases with increasing temperature; It was determined that the CO gas has the highest activation energy. Adsorption kinetics of gases were controlled with electrostatic interaction. © 2020 Hydrogen Energy Publications LLCArticle Citation - WoS: 12Citation - Scopus: 13Development of Agcl-Tio2 Xerogels Entrapped Antibacterial Polyacrylonitrile Membranes: the Effect of High Salinity Water on Silver Release, Antibiofouling and Antibacterial Efficacies(Elsevier Ltd., 2020) Uz, Metin; Yaşar Mahlıçlı, Filiz; Şeker, Erol; Alsoy Altınkaya, SacideSilver-containing antibacterial membranes are commonly used to control biofouling during bacteria filtration. Unfortunately, fast and uncontrolled release of silver to water is a challenge since this causes mass accumulation of silver in water resources and insufficient long-term antimicrobial effect. To overcome these disadvantages, we propose to add AgCl-TiO2 xerogels (0–0.8 wt%) in the polyacrylonitrile membranes. The long-term silver retaining of the membranes was evaluated by measuring the silver release under filtration of deionized water in the absence and the presence of 1 M NaCl up to 5 days. The antibiofouling and the antibacterial efficacies were determined by measuring the changes in antibacterial activity and DI water flux of the membranes at the end of 5 days of E. coli filtration. The 0.2 wt% AgCl-TiO2 xerogel incorporated polyacrylonitrile membrane demonstrated a constant ~1 ?g of silver release/cm2 per filtration cycle after a total filtration of 0.05 L/cm2 with 1 M NaCl solution. Additionally, it showed antibacterial efficacy and ~100% recovery of deionized water flux by simple backwashing with water after having been used in many E. coli filtration cycles. Thus, this membrane could potentially be used up to ~5.8 years for 8000 h a year for the filtration of high salinity water. Statement of novelty: Silver-containing antibacterial membranes are commonly used to control biofouling during bacteria filtration. Uncontrolled release of silver from the membrane causes massive silver accumulation in water which in turn leads to contamination of water resources and threat to aquatic organisms. Although silver release is strongly influenced by the salinity of water, the release data was collected through filtration of pure DI water or tap water in literature. To overcome the shortcomings of the published studies, we propose to use AgCl-TiO2 xerogels in membranes due to low solubility of AgCl in water and measure the release by filtering high-salinity water. © 2020 Elsevier B.V.Article Citation - WoS: 8Citation - Scopus: 8Synthesis of Butyl Glucoside Over Sulphated Zr-Sba and Tungstophosphoric Acid Incorporated Sba-15 Catalysts(Elsevier Ltd., 2021) Mutlu, Nahide Nuran; Yılmaz, SelahattinGlycosidation of glucose with n-butanol was studied over sulphated Zr incorporated SBA-15 and tungstophosphoric acid (TPA) incorporated SBA-15 catalysts. The catalysts were prepared with different Zr, TPA and SO4 amounts via hydrothermal synthesis. SBA-15 structure was preserved and Zr and TPA were successfully incorporated. Sulphation improved the acidity of Zr-SBA-15 and the ratio of Brønsted to Lewis acid sites (B/L) increased. Thus, much higher butyl glucoside yields (about 70 %) were obtained over SO4/Zr-SBA-15 catalysts. However, 15 % activity loss was observed after 2 re-use due to sulphate leaching. TPA-SBA-15 catalysts had the highest B/L and provided very high catalytic activity with butyl glucoside yields above 95 %. The initial rate of butyl glucoside formation over TPA-SBA-15 catalysts were close to that of H2SO4. These catalysts were found stable and reusable. Reaction temperature and catalysts amount was studied as the reaction parameters over the most active and selective catalyst. © 2020 Elsevier B.V.