In this work, batch wise esterification of lactic acid and ethanol was carried out using different cation-exchange resins including amberlyst 15, amberlyst 16, dowex 50W8x and amberlyst 36 as heterogeneous catalysts. The Zeiss EVO LS10 Scanning electron microscopy/energy dispersive x-ray analyser (SEM/EDXA) was used to examine the surface morphology of the resin catalysts before and after the esterification reaction process. The EDXA of the catalysts showed the presence of sulphur with the highest peak on the spectra. The SEM of the commercial resin catalysts showed a clear surface with no crack before the esterification reaction. Amberlyst 36 showed a greater thermal stability after the esterification reaction process. The order of the surface integrity from the SEM morphology of the resin catalysts after the esterification process was Amberlyst 36 > dowex 50W8x. Gas chromatography equipped with mass spectrometry (GC- MS) detector was used to analyse the reaction products. Ion 45 on the mass spectra confirmed that the esterification product was in accordance with the library mass spectra of the commercial ethyl lactate solvent. The agitation time was found to increase with increase in concentration indicating a non-mass transfer limitation at 60 oC. The reaction product catalysed with amberlyst 36 was found to elute at faster at 1.441 min in contrast to the commercial ethyl lactate solvent at 2.124 min indicating a higher reaction rate of the resin catalysts.
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