Preparation of D-tartaric Acid Modified Multi-walled Carbon Nanotubes for Resolution of Propranolol Enantiomers

In this paper, multi-walled carbon nanotubes (MWCNTs) were oxidized by 30 w% hydrogen peroxide to introduce hydroxyl groups and carboxyl groups on it. Catalyzed by p-toluenesulfonic acid, D-tartaric acid (DTA) was grafted onto MWCNTs by an esterification reaction. Fourier transform infrared spectroscopy and high resolution transmission electron microscopy were used to elucidate the introduced groups and the morphologies changes of the MWCNTs samples. The D-tartaric acid modified MWCNTs were used as chiral im pregnating reagents for thin-layer chromatography for enantioseparation of propranolol enantiomers, and the chiral separation factor was achieved over 7.23 by a mixed solvent of acetonitrile-tert-butanol-acetic acid (volume ratio is 49:49:2) as developing solvent.