Yazar "Yurdakoc, Kadir" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    Benzylation of benzene and toluene with benzylchloride over clay-based acid catalysts
    (Mrs Pushpa Agarwal, 2006) Durap, Feyyaz; Akcay, Mehmet; Yurdakoc, Kadir
    The pillared clay catalysts were calcined after in corporation of metal polycation ions with exchangeable cations and water. Friedel-Crafts alkylations of aromatic hydrocarbons were carried out in the presence of clay catalysts originating from bentonite. In these reactions, it has been found that pillared clays have excellent catalytic activity. It was found that iron pillared clay (Fe-PILC) was the more efficient catalyst producing quantitative conversion with greatly reduced amounts of catalysts in short reaction period. Their efficiency is attributed to the higher Fe3+, Cr3+ and Al3+ contents in the catalysts and pillaring effect. The clays have both Bronsted and Lewis acidities which were determined by pyridine adsorption-desorption and in situ FTIR technique.
  • [ X ]
    Öğe
    Preparation and characterization of Cr- and Fe-pillared bentonites by using CrCl3, FeCl3, Cr(acaC)3 and Fe(acac)3 as precursors
    (Elsevier, 2008) Yurdakoc, Mueruevvet; Akcay, Mehmet; Tonbul, Yalcin; Ok, Fatih; Yurdakoc, Kadir
    Four pillared bentonites (Cr-PILB, Cr(acaC)(3)-PILB, Fe-PILB and Fe(acaC)(3)-PILB were prepared and characterized by X-ray diffraction (XRD), nitrogen sorption measurements and thermogravimetric (TG) analysis. The surface acidities of the samples and their structures were also investigated in the gas phase adsorption data of pyridine by the aid of FT-IR spectroscopic techniques. The XRD data and FT-IR spectra of the samples reflected mainly the structure of bentonite. The nitrogen adsorption-desorption isotherms of the samples were Type II shaped and showed in general mesoporous structures with pore openings of 4 nm. Two steps mass losses were observed in the TGA thermograms of B, Cr-PILB and Fe-PILB, while three steps mass losses were detected in the case of Cr(acaC)(3)-PILB and Fe(acaC)(3)-PILB. IR study by the adsorption of pyridine on the samples showed both Lewis and Bronsted acid sites on their surfaces. (C) 2007 Elsevier Inc. All rights reserved.
  • [ X ]
    Öğe
    Removal of nicotine and its pharmaceutical derivatives from aqueous solution by raw bentonite and dodecylammonium-bentonite
    (Natl Inst Science Communication, 2008) Akcay, Guelten; Yurdakoc, Kadir
    Dodecylammonium bentonite (DAB) and bentonite (B) were used as sorbents for nicotine (N), nicotinic acid (NA), isonicotinic acid (INA), nicotinic acid hydrazide (NH), and iso-nicotinic acid hydrazide (INH). The obtained data were modeled according to Freundlich and Dubinin-Raduslikevich adsorption isotherms. Sorption energy (E) and adsorption capacity (q(m)) for N and its derivatives adsorbing on DAB and raw B were estimated using Dubinin-Raduslikevich (D-R) equation. Sorption energy of N and its pharmaceutical derivatives on DAB and raw B increased in order of NA < INA < N=INH < NH and INI-I < NH < N < NA < INA, respectively.