Journal of Materials Science and Engineering with Advanced Technology

Lactic acid (LA) is widely used in the food, chemical and pharmaceutical industries.Recently there has been an increase in demand for lactic acid as a raw material for the production of biodegradable polymers.LA can be manufactured either by synthetic routes or by a fermentation process.The methods for recovery of lactic acid are solvent extraction, adsorption on an ion-exchange resin, reactive distillation and electro dialysis.In this study, the lactic acid recovery was carried out by reactive distillation using cation exchange resin as a catalyst.Reactive distillation involved, two reactions mainly esterification and hydrolysis.The effect of operating variables such as catalyst loading, temperature of reaction, reaction time and reactant mole ratio on the yield of methyl lactate was studied.Further, poly (d,l-lactic acid) was synthesized by microwave radiation and azeotropic polycondensation technique using stannous octoate as a catalyst.The effects of catalyst concentration, microwave irradiation power, reaction time and reaction temperature on molecular weight of polymer were discussed.The obtained products were characterized with differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and Fourier transform infrared spectroscopy (FTIR).