Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 15Citation - Scopus: 19Aqueous Interactions of Zeolitic Material in Acidic and Basic Solutions(Elsevier Ltd., 2010) Polatoğlu, İlker; Çakıcıoğlu Özkan, Seher Fehime; Özkan, Seher Fehime; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyAqueous interactions of natural zeolitic material in as-received and modified forms were studied. The zeolitic materials was interacted with acidic (hydrochloric acid, lactic acid, acetic acid) and basic (sodium hydroxide) solutions. Ion exchange, adsorption, complex formation, precipitation and cation hydrolysis were possible interaction mechanisms affected by the amount and cation content of zeolite and pH. The dominant mechanisms seemed to be ion exchange and adsorption in HCl solution when zeolite was used in the as-received form, but dissociation of outer-sphere complexes when modified zeolite was used. In lactic acid, acetic acid as well as the basic solution, cation hydrolysis and complex formation were additional mechanism in the interactions. © 2010 Elsevier Inc. All rights reserved.Article Citation - WoS: 47Citation - Scopus: 52Isomerization of ?-Pinene Over Ion-Exchanged Natural Zeolites(Elsevier Ltd., 2003) Özkan, Fehime; Özkan, Seher Fehime; Akpolat, Oğuz; Beşün, Nurgün; Murzin, Dmitry Yu.; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyCatalysts prepared by ion exchange of clinoptilolite-based natural zeolite tuffs with NH4 +, Ba2+ and Pb2+ were investigated in the isomerization reaction of α-pinene at atmospheric pressure under nitrogen flow. Activity and selectivity to mono-, bi- and tricyclic products were correlated with acidity strength.Article Citation - WoS: 12Citation - Scopus: 17Dynamics of Water Vapor Adsorption on Humidity-Indicating Silica Gel(Elsevier Ltd., 1998) Balköse, Devrim; Ulutan, Sevgi; Ülkü, Semra; Özkan, Seher Fehime; Balköse, Devrim; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyWell-defined CoCl2-containing silica gels were prepared by impregnation of the aqueous solution of the salt to silica hydrogel, drying and aging methods. Silica gels having 392-437 m2 g-1 surface area and 0.21-0.37 cm3 g-1 pore volume and having an average particle size of 3 mm were obtained. Aging in CoCl2 solutions decreased the surface area of silica gels from 540 cm2 g-1 to 392-430 m2 g-1 and pore volume from 0.27 to 0.21-0.23 cm3 g-1 for CoCl2 concentration smaller than 0.28 mol dm-3 in silica gel. Adsorbed water desorbed from the gels absorbing 1917-2555 J g-1 energy as determined by differential scanning calorimetry. The CoCl2-containing gels were successfully used in dynamic column experiments, with linear relation between velocities of inlet air and movement of blue to pink boundary. The colour change also makes the detection of the defects in column filling which causes air channelling