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Publication Metadata only A Vibrational Spectroscopic Study of the Adsorption of 4 4 Bipyridiyl by Smectite Group Clay Minerals From Anatolia Turkey(Kluwer Academic Publishers, 1993-06) Davies, J. Eric D.; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 1012The adsorption of 4,4′-bipyridyl by natural sepiolite and smectite group clay minerals (bentonite, hectorite and saponite) from Anatolia (Turkey) has been studied using vibrational spectroscopy. Investigation of Fourier-transform infrared and Fourier-transform Raman spectra of adsorbed 4,4′-bipyridyl indicate the presence of chemisorbed species. However, any evidence for the generation of anionic species on the surface of the phyllosilicates has not been detected. It is proposed that the adsorbed bipyridyl molecules on sepiolite are centrosymmetric and H-bonded to the surface hydroxyls through both the nitrogen lone pairs as bidentate ligands. The adsorbed bipyridyl molecules on the smectite group clays are coordinated to exchangeable cations both directly and also indirectly through water as monodentate ligands. XRD patterns of the clays studied are also recorded.Publication Metadata only FT-IR spectroscopic investigation of adsorption of pyrimidine on sepiolite and montmorillonite from Anatolia(Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands, 2003-06) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 10127The adsorption of pyrimidine ( PM) on natural montmorillonite and sepiolite from Turkey was investigated by FT-IR spectroscopy. The intercalation of PM within montmorillonite has been shown by X-ray diffraction to increase the interlayer spacing. The spectroscopic results indicate that PM molecules adsorbed on sepiolite are coordinated to Lewis acidic centers or surface hydroxyls by H-bonding interaction through one of the pyrimidine ring nitrogen lone pairs. Moreover, some of the adsorbed PM molecules may enter the interior channels of the sepiolite structure and replace zeolitic water. The intercalated PM molecules within montmorillonite are coordinated to exchangeable cations directly or indirectly through water bridges.Publication Metadata only FT-IR spectroscopic investigations adsorption of pyrazinamide and 4-aminopyrimidine by clays(SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS, 2004-02) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANILThe adsorption of pyrazinamide (PZA) and 4-aminopyrimidine (4APM) on natural sepiolite, loughlinite (Na-sepiolite), natural and ion-exchanged montmorillonite (Co- or Cu-montmorillonite) has been investigated using FT-IR spectroscopy. The intercalation of pyrazinamide and 4-aminopyrimidine within natural and ion-exchanged montmorillonites has been shown by X-ray diffraction to increase the interlayer spacing. PZA and 4APM interacted with montmorillonites by direct or indirect coordination ( through water molecules) to the exchangeable cations. The spectroscopic results indicate that PZA or 4APM molecules adsorbed on sepiolite and loughlinite are coordinated to Lewis acidic centers or surface hydroxyls by H-bonding interaction through either one of the pyrimidine ring nitrogen lone pairs ( in the case of 4APM) or carbonyl group ( in the case of PZA).Publication Metadata only Adsorption of 2 2 Bipyridyl onto Sepiolite Attapulgite and Smectite Group Clay Minerals from Anatolia FT IR and FT Raman Spectra of Surface and Intercalated Species(Kluwer Academic Publishers, 1994-06) Davies, J. Eric D.; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 10127The adsorption of 2,2′-bipyridyl by natural sepiolite, attapulgite, hectorite, saponite and natural and ion exchanged (Mn, Fe, Co, Ni, Cu, Zn or Sn) bentonites has been investigated by FT-IR and FT-Raman spectroscopy. Spectroscopic results indicate that most of the adsorbed molecules are coordinated to either exchangeable cations (in the case of smectite group clays) or Lewis acidic centres (in the case of sepiolite and attapulgite) as bidentate ligands. The formation of monoanionic surface species has also been detected, to a relatively small extent. No physisorbed surface species has been observed. XRD patterns and UV-visible spectra of the samples are also recorded for additional information.Publication Metadata only FT-IR spectra of natural loughlinite (Na-sepiolite) and adsorption of pyrimidine on loughlinite(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2004-11-01) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANILFT-IR spectroscopy has been used to characterise natural loughlinite and the adsorption of pyrimidine. A comparison of the spectra of loughlinite and sepiolite are given. The adsorption of pyrimidine was on the loughlinite Lewis acid cites through the pyrimidine lone pairs. Moreover. some of the adsorbed pyrimidine molecules may coordinate to surface SiOH groups. (C) 2004 Elsevier B.V. All rights reserved.Publication Metadata only Adsorption and interaction of 2-aminopyridine with loughlinite (Na-sepiolite) from Anatolia(ASIAN JOURNAL OF CHEMISTRY, 11/100 RAJENDRA NAGAR, SECTOR 3,, SAHIBABAD 201 005, GHAZIABAD, INDIA, 2008-06) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR10127; TR111424FT-IR spectroscopy has been used to characterize adsorption and interaction of 2-aminopyridine by loughlinite, which belongs to palygorskite-sepiolite group of phyllosilicates class of clay minerals. The spectroscopic results indicate generation of 2-aminopyridinium cations. Cationic and neutral surface species adsorbed on loughlinite are coordinated to Bronsted acidic sites and surface hydroxyls (by H-bonding interaction through pyridine ring nitrogen lone pairs), respectively. It must be noted that the adsorption of 2-aminopyridine affected the hydroxyl group vibrations of loughlinite.Publication Metadata only Adsorption Of 3-And 4-Aminopyridine On Loughlinite-An IR Spectroscopic Study(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2010-05-26) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR10127; TR111424In this study adsorption of 3- and 4-aminopyridine on loughlinite (Na-sepiolite) have been investigated by FT-IR spectroscopy. Spectroscopic results indicate that sorbed aminopyridine molecules onto loughlinite are coordinated to Lewis acidic centers, zeolitic/bound water molecules, and surface silanol groups by hydrogen bonding interaction through pyridine ring nitrogen lone pairs. Some of the adsorbed molecules coordinate to Bronsted acidic centers and aminopyridinium cationic surface species are also generated. (C) 2010 Elsevier B.V. All rights reserved.Publication Metadata only Vibrational Spectroscopic Investigation of 2,2 '-Bipyridine Adsorbed on Loughlinite from Aqueous Suspensions(Asian Journal Of Chemistry, 11/100 Rajendra Nagar, Sector 3,, Sahibabad 201 005, Ghaziabad, India, 2010-01) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; TR111424; TR10127The adsorption of 2,2'-bipyridine onto loughlinite (Na-sepiolite) has been investigated by FT-IR and micro-Raman spectroscopy. Spectroscopic results indicate the formation of monoanionic surface species. Most of the adsorbed molecules are incorporated in the channels of the clay structure and coordinated to Lewis acidic centers directly or indirectly through water molecules.Publication Metadata only FT-IR and FT-Raman spectroscopic studies of adsorption of isoniazid by montmorillonite and saponite(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2008-11-20) AKYÜZ, ZEKİ TANIL; AKYÜZ, SEVİM; TR10127; TR111424The adsorption of isoniazid on natural montmorillonite and saponite from Anatolia was investigated by FT-IR and FT-Raman spectroscopy. The intercalation of isoniazid within these clays has been shown by Xray diffraction to increase the interlayer spacing. Vibrational spectroscopy indicates that isoniazid molecules, intercalated into the layers of montmorillonite or saponite, are coordinated to exchangeable cations directly or indirectly through water bridges. It is concluded that the endocyclic nitrogen is mainly involved in the coordination. The carbonyl group oxygen, however, may be involved in a weak H-bonding interaction with water molecules. (C) 2008 Elsevier B.V. All rights reserved.Publication Metadata only Study on the interaction of nicotinamide with sepiolite, loughlinite and palygorskite by IR spectroscopy(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2005-06-03) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANILThe adsorption of nicotinamide by two different Anatolian sepiolites (Eskisehir sepiolite and Bolu-Kibriscik sepiolite), loughlinite (Na-sepiolite), and palygorskite has been investigated using FT-IR spectrometry. The spectroscopic results indicate that nicotinamide molecules adsorbed on sepiolite, loughlinite and palygorskite are coordinated to surface hydroxyls and/or to Lewis acidic centers by hydrogen bonding interaction through the ring nitrogen lone pairs. Amino group nitrogen is found to be relatively in active to adsorbing sites. Some intensity and frequency changes in the OH stretching and deformation bands of surface hydroxyls (Si-OH) of the nicotinamide treated sepiolite and loughlinite were observed. But these bands are found to be less affected by the adsorption of nicotinamide in the case of palygorskite, probably because the surface Si-OH groups in palygorskite appear to be less abundant than in sepiolite or loughlinite. (c) 2004 Elsevier B.V. All rights reserved.