Solvent Selection for a Reactive and Extractive Distillation Process by Headspace Gas Chromatography

Abstract

The aim of this study is to determine the best solvent for the transesterification of the methanol and methyl acetate azeotropic mixture with n-butanol using the extractive and reactive distillation technology. A preliminary selection according to heuristics and physical properties was completed. Selectivity at infinite dilution for 40 systems was measured using headspace gas chromatography. This criteria help to cluster solvents into groups, but a definitive selection cannot be made. To consider the industrial application, the importance of peripheral properties was discussed. In addition, reactive and nonreactive residue curve maps analysis was made to reject those promising solvents without any feasible separation sequence (distillation boundary). Taking into account all these considerations, n-alkanes, alkilbenzenes, and, in particular, o-xylene were found to be the best alternatives.

Keywords:

• Headspace gas chromatography
• Solvent selection
• Selectivity
• Reactive distillation
• Extractive distillation

Acknowledgments

The authors would like to thank Cervezas Damm s.a. (Barcelona, Spain), Aspen Technology (Cambridge, MA), and DDBST GmbH (Oldenburg, Germany) for providing the necessary facilities. One of the authors (L. Jiménez) gratefully acknowledges the financial support from Fundación Caja de Madrid.