In this work, the characteristics and enhancement of pervaporation for
the separation of various alcohols from hydrocarbon mixtures are demo
nstrated. Experiments were performed through a composite plate-and-fra
me type hydrophilic PVA (polyvinyl alcohol) membrane at a constant per
meate vacuum pressure of 6.5 mmHg and at temperatures of 30, 45 and 60
degrees C. The Wilson equation was used to describe the activity coef
ficients for the system. The analysis is presented in terms of the var
iations in permeation flux, permeability and selectivity. The results
show that as the concentration of alcohols in the feed increases, the
permeability, selectivity and total flux also increase. By increasing
the temperature, the permeabilities increase while selectivity decreas
es. However, the experimental results show that at temperatures of 30
and 45 degrees C a good degree of separation of alcohols from a hydroc
arbon mixture is possible by the pervaporation technique using a PVA m
embrane with a selectivity of greater than 10. (C) 1997 Published by E
lsevier Science B.V.