Selective synthesis of natural benzaldehyde by hydrolysis of cinnamaldehyde using novel hydrotalcite catalyst

Abstract

A novel Al–Mg hydrotalcite catalyst was synthesized by using combustion synthesis with glycerol as fuel. It was fully characterized. It was used in the hydrolysis of cinnamaldehyde to produce natural benzaldehyde. This is the first report of using a heterogeneous hydrotalcite for making natural benzaldehyde. The effects of different parameters on rate of hydrolysis were studied systematically to establish the kinetics of reaction. The reaction follows pseudo first order kinetics at a fixed catalyst loading with apparent activation energy of 10.00 kcal/mol. The reaction is intrinsically kinetically controlled. The maximum conversion obtained at optimum conditions was 70% in 4 h with 100% selectivity towards natural benzaldehyde. The catalyst can be reused several times without loss of activity. Both the catalyst synthesis and application in retro-aldol reaction are novel aspects of the current work.