Fourier transform Raman and fourier transform ir spectroscopic investigation of pyrazine adsorbed by sepiolite and bentonite from anatolia

Abstract

The adsorption of pyrazine by two different Anatolian sepiolites and by natural and ion‐exchanged (Fe, Co, Cu and Sn) bentonites was investigated by vibrational spectroscopy. The spectroscopic results indicate that the pyrazine molecules adsorbed on sepiolite and bentonites are coordinated to either surface hydroxyls by H‐bonding interaction (in the case of sepiolite) or to exchangeable cations (in the case of bentonites) through both nitrogen lone pairs as bidentate ligands. X‐ray diffraction patterns of the clays were also recorded and the basal spacings of pyrazine‐treated natural and ion‐exchanged bentonites were found to be around 14.7 Å. The results suggest that pyrazine molecules intercalate the interlayers of bentonite with a monolayer arrangement.