Theoretical and practical approach to the dealcoholization of water-ethanol mixtures and red wine by osmotic distillation

Abstract

Osmotic distillation (OD) has been a subject of interest during the last few years due to its promising application in the production of low alcohol strength wines. This work focuses on the partial dealcoholization (-3 v/v%) of red wine (tempranillo) by OD, carrying out an experimental and theoretical process analysis. The dealcoholization process was performed using a polypropylene hollow fiber module at different experimental conditions whose influence in the ethanol behavior was evaluated. At the best tested conditions, the study of the behavior of ethanol and other five different alcohols (both aliphatic and aromatic) as a function of their volatility (Henry’s constant) and their interaction with the membrane (in terms of Hansen solubility parameters) validated the theoretical model proposed. As a result, a transport resistance expression that includes the alcohol-membrane interaction was successfully developed. This allowed to reduce the error between the experimental and theoretical alcohols concentrations in a relatively wide range of working conditions.