Liquid phase mass transfer rates kLS for the absorption of oxygen in tap water and in aqueous ionic solutions have been determined in two closed stirred tank contactors for a power input between 3 and 70 W/kg and (impeller diameter)f(tank diameter) ratios DifT of 0.3, 0.35 and 0.4. The contactors had diameters\ud
of 0. I9 and 0.6 m. The dispersed phase fraction was 1% by volume in all experiments. The values of kLS were determined using two different techniques:\ud
(1) a transient physical absorption method; and (2) the sulphite method
