Effect of vitamin C template on morphology and structure of alumina: emerging application in enantiomer separation

Mesoporous nano-aluminas were prepared using aluminium isopropoxide, vitamin C (VC as a chiral template and a co-structural directing agent with molar ratios of 50:50 and 90:10) and water. These compositions when dried at 120 °C and calcined at 250, 350 and 500 °C for 8 h under air atmosphere transformed to boehmite and γ-alumina depending on the concentration of VC. The influence of vitamin C and its degradation products on the morphology and texture of alumina was investigated by the means of XRD, FT-IR, SEM, EDX, TEM, TGA, DSC, BET and N2 adsorption–desorption isotherm. Mesoporous aluminas possess excellent characteristics such as large surface area (ca. 394 m2/g), 0.4 cm3/g pore volume and narrow pore size distributions that can be synthesized through a facile and green procedure. In addition, the enantiomers of propranolol hydrochloride were successfully resolved from its racemate using Al50VC50T350 (AlMolar ratio of the Aluminium isopropoxide, VCMolar ratio of the Vitamin C,TTemperature) (Rs = 2.5) as chiral stationary phase. The synthesis of chiral stationary phase was accomplished in a green, facile and inexpensive procedure that is of paramount importance in food and pharmaceutical industries.