Comparative Investigation of Atmospheric, Vacuum, and Reactive Distillation for Enhanced Separation Efficiency of Lactic Acid and Formic Acid from Glycerol Conversion Mixtures Enggal Nurisman (a), Susila Arita (a*), Leily Nurul Komariah (a), Putra Rajasa (a), and Dina Aprillia Permatasari (a)
a) Department of Chemical Engineering, Faculty of Engineering, Sriwijaya University, Indonesia
*susilaarita[at]yahoo.com
Abstract
Glycerol, an abundant byproduct of the biodiesel industry, can be converted into economically valuable primary products, namely lactic acid and formic acid, although it still contains other byproducts. Therefore, a large-capacity separation technology, namely distillation, is required. This study studied the separation of lactic acid and formic acid from a glycerol conversion mixture using a variety of methods, namely atmospheric distillation, vacuum distillation, and reactive distillation. The analysis focused on the physical-chemical properties approach and percent recovery. The process began by comparing atmospheric distillation and vacuum distillation methods. The results showed that separation using the vacuum distillation method obtained a density ratio and mass ratio of the mixture in both the condensate and residue that were actually better than the atmospheric distillation method due to the degradation of formic acid and lactic acid at high temperatures and pressures. In addition, it was supported by a greater recovery of lactic acid of 92.363% and a greater recovery of glycerol of 97.211% in the residue in the vacuum distillation method. Further separation of lactic acid was carried out through reactive distillation at varying temperatures and substrate mixtures, reflecting the residue from the previous stage. Lactate recovery increased with increasing temperature up to 125 celsius and then decreased at higher temperatures.
