Kinetic Study of Ethyl Lactate Synthesis from Magnesium Lactate

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Boonpradab Daengpradab
Panarat Rattanaphanee


Ethyl lactate is widely used as solvent for several industries and usually produced from lactic acid esterification with ethanol. In order to lower the production cost, attempt to synthesis ethyl lactate directly from fermentation-derived magnesium lactate was made. In this research, kinetics of magnesium lactate esterification with ethanol catalyzed by sulfuric acid was studied. Effect of reaction temperature, initial feed molar ratio, and catalyst loading on the production yield were investigated. Specific rate and equilibrium constant were determined and found that both parameters were influenced by reaction temperature, initial feed molar ratio, and catalyst loading. Relationship between the rate constant and process variables was elucidated. The result was compared with commercial lactic acid esterification under the same process condition. It was found that the values of kinetic parameters obtained from magnesium lactate esterification were lower, which could be due to the presence of impurities in fermentation-derived magnesium lactate.

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