Pervaporation of alcoholic beverages-the coupling effects between ethanol and aroma compounds

In pervaporation (PV) of alcoholic beverages, complicated interactions between ethanol and aroma compounds often exist and affect their PV performance. In this paper, a series of model solutions containing ethanol and six typical aroma compounds in alcoholic beverages were experimented. The permeability coefficient was introduced to discuss the coupling effects. The results showed that the solubility thermodynamics, with the feed solution activity coefficient had a dominant effect on the permeability rather than diffusion factor. The presence of aroma compounds decreased the permeability coefficient and separation factor of ethanol from those in ethanol-water binary solutions, while affected little on the fluxes. The effect of ethanol feed concentration on mass transfer of each compound was much related to the solubility properties of the compound in ethanol and water. Little interactions exist in PV process of diluted solution containing these aroma compounds within 1000 ppm.