Absorption of water vapor into the 50% lithium bromide solution with four eight-carbon alcohol additives such as n-octanol, 2-octanol, 3-octanol, and 2-ethyl-l-hexanol were investigated by using a simple stagnant pool absorber. Four The experimental apparatus could be used with good confidence and accuracy particularly for studying mass transfer enhancement over the effective range of additive concentration which, in this work, is mostly between 10 and 500 ppm. A vigorous interfacial turbulence was observed during absorption process suing additives. The water vapor absorption rate remarkably increased with increasing the additive concentrations up to about 200 ppm and then stopped increasing above 200ppm for all the systems considered. The onset additive concentrations for enhancing mass transfer were located between 5 and 8 ppm for all systems except two systems of the 50% lithium bromide solution with 3-octanol and 70% lithium bromide + zinc chloride solution with 2-ethyl-1 hexanol for which the corresponding concentrations were 2.5 and 35 ppm, respectively.