Aim and Objectives:
This research work deals with the highly selective oxidation of benzyl alcohol to
benzaldehyde by palladium doped graphene oxide catalyst which was synthesized by a modified Hummer’s method. The
effect of reaction parameters like temperature, time and catalyst loading were studied. It was found that fine tuning of
reaction temperature and presence of small amount of benzyl alcohol in product prevents undesirable formation of benzoic
acid crystals which forms on auto oxidation of benzaldehyde. Benzoic acid or substituted benzoic acid formation was
hindered by the presence of < 2% benzyl alcohol at a reaction temperature of 50˚C which was further supported by
palladium doped graphene oxide catalyst.
Materials and Methods:
Modified Hummer’s method was used for the synthesis of graphene oxide and palladium doped
graphene oxide was synthesized by insitu method in which graphene oxide dispersed in 20mL of distilled water was
ultrasonicated for 2h. Palladium solution was added and it was further ultrasonicated for 30min for homogeneous deposition
of palladium on graphene oxide support. To this, 2 mL of sodium borohydride solution was added and stirred at room
temperature for 4h. The resulting solution was centrifuged and the residue was dried at 60°C for 12 h.
Results:
The morphological characteristics and the functional groups of supported catalyst were characterized by X-ray
diffraction, Field emission scanning spectroscopy, Fourier transform infrared spectroscopy and the produced benzaldehyde
was characterized by gas chromatography.
Conclusion:
PdGO catalyst was prepared using sodium borohydride as a reducing agent by modified Hummer’s method and
utilized for the oxidation of benzyl alcohol to benzaldehyde. A maximum conversion of 89% and selectivity of 99% was
obtained and the catalyst could be reused upto five times without any compromise on conversion and selectivity.
Eco-efficient preparation of a N-doped graphene equivalent and its application to metal free selective oxidation reaction
