Separation and Semi-Empiric Modeling of Ethanol–Water Solutions by Pervaporation Using PDMS Membrane

Abstract

High energy demand, competitive fuel prices and the need for environmentally friendly processes have led to the constant development of the alcohol industry. Pervaporation is seen as a separation process, with low energy consumption, which has a high potential for application in the fermentation and dehydration of ethanol. This work presents the experimental ethanol recovery by pervaporation and the semi-empirical model of partial fluxes. Total permeate fluxes between 15.6–68.6 mol m−2 h−1 (289–1565 g m−2 h−1), separation factor between 3.4–6.4 and ethanol molar fraction between 16–171 mM (4–35 wt%) were obtained using ethanol feed concentrations between 4–37 mM (1–9 wt%), temperature between 34–50 ∘C and commercial polydimethylsiloxane (PDMS) membrane. From the experimental data a semi-empirical model describing the behavior of partial-permeate fluxes was developed considering the effect of both the temperature and the composition of the feed, and the behavior of the apparent activation energy. Therefore, the model obtained shows a modified Arrhenius-type behavior that calculates with high precision the partial-permeate fluxes. Furthermore, the versatility of the model was demonstrated in process such as ethanol recovery and both ethanol and butanol dehydration.

Machine Learning for Polymer Design to Enhance Pervaporation-Based Organic Recovery

“…However, the diffusion rate of H 2 O increases more significantly due to its smaller molecular diameter (e.g., 0.26 nm for H 2 O vs 0.52 nm for ethanol). As a result, the selectivity decreases. , …”

Comprehensive analysis on anomalous phenomenon of ethanol‐soluble poly(vinyl butyral) membrane for ethanol recovery via pervaporation

“…Membrane-based pervaporation (PV) technology has become one of the most promising processes for ethanol/water mixtures separation due to its low energy requirement and environment-friendly characteristics. [1][2][3][4] Generally, PV membranes for the separation of ethanol aqueous solutions can be divided into water-and ethanolpermselective membranes, which preferentially permeate water and ethanol, respectively. [5][6][7] Many studies have concentrated on developing water-permselective PV membranes, [8][9][10] which are beneficial to separate mixtures with high-concentration ethanol.…”