WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

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Department: search.filters.department.İzmir Institute of Technology. Chemical EngineeringInstitution Author: search.filters.institutionAuthor.Artok, Levent

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Now showing 1 - 3 of 3
  • Article
    Citation - WoS: 36
    Citation - Scopus: 40
    The Kinetics of Citral Hydrogenation Over Pd Supported on Clinoptilolite Rich Natural Zeolite
    (Elsevier Ltd., 2005) Yılmaz, Selahattin; Uçar, Şule; Artok, Levent; Güleç, Hilal
    The liquid phase hydrogenation of citral has been investigated over Pd (2.42%) supported on clinoptilolite rich natural zeolite catalyst for different reaction conditions. The zeolite support did not affect the active metal properties. This was attributed to the large size of Pd particles on the support. High selectivity (90%) to citronellal was obtained at complete conversion of citral. The catalytic activity increased with reaction temperature (80, 100, 120°C) following an Arrhenius behaviour, while selectivity remained constant for a given conversion. Selectivity to citronellal increased from 78 to 90% with increase in the amount of catalyst in the reaction solution (Citral/Pd mole ratio 293, 176 and 105). The spent catalyst regained its fresh activity and selectivity upon regeneration.
  • Article
    Citation - WoS: 56
    Citation - Scopus: 59
    Suzuki Cross-Coupling Reaction of Aryl Halides With Arylboronic Acids Catalysed by Pd(ii)-Nay Zeolite
    (Elsevier Ltd., 2003) Bulut, Hatice; Artok, Levent; Yılmaz, Selahattin
    Pd(II)-exchanged NaY zeolite showed high activity in the Suzuki cross-coupling reactions of aryl bromides and iodides without added ligands. The DMF:water ratio, and the type and amount of base were found to be critical for the efficiency of the reaction. The catalyst is reusable after regeneration.
  • Conference Object
    Citation - WoS: 7
    Citation - Scopus: 8
    Acylation of 2-Methoxynaphthalene Over Ion-Exchanged Ss-Zeolite
    (Elsevier Ltd., 2002) Kantarlı, İsmail Cem; Artok, Levent; Bulut, Hatice; Yılmaz, Selahattin; Ülkü, Semra
    Friedel-Crafts acylation of 2-Methoxynaphthalene was carried out over various ion-exchanged β zeolites (Mn+β, where Mn+: In3+, Zn2+, Al3+, Fe3+, La3+) with various anhydride (acetic, propionic and benzoic anhydrides), or acyl chloride (acetyl, propionyl and benzoyl chlorides) acylating reagents. The results suggested that selectivity towards the 6-substituted products was higher with the larger size anhydrides, propionic and benzoic anhydrides. The metal cation type within the zeolite significantly influenced the extent of conversion and product distribution. That La3+ exchanged zeolite displayed higher selectivity for the 6-position acylated product with anhydrides ascribed mainly to narrowing of channels by the presence of La(OH)2+ ions that leave no room for the formation of more bulky isomeric forms and to enhanced Bronsted acidity of the zeolite. With acyl chlorides, the recovery of ketone products was found to be remarkably low. 1-Acyl-2-methoxynaphthalenes actively underwent deacylation when acyl chlorides were used as the acylation reagent.