The present invention relates to an enantioselective separation of racemic mixtures of amino acids like alanine and leucine using chiral polystyrene microspheres. It provides a simple and efficient separation process by using cost-effective commodity polymer like polystyrene after simple post polymer modifications which involves simple filtration without using any high end chromatographic instrument. The present process provides the preparation of chiral modified protected or deprotected polystyrene powder. The present invention provides a process of preparing the modified polystyrene to form the deprotected polystyrene along with the process of preparation of the modified polystyrene compound in fiber form or microspheres form wherein the change in the morphology is observed from irregular to fibrous upon deprotecting the protected polymer. This process achieves high separation efficiency and % Enantiomeric excess values (% ee) value.