The dynamic surface renewal model of Maucci et al. (2001) is applied to transient mass transfer problems and extended to transient heat transfer measurements in pulsating, two-phase flows. The model is also used to simulate mass transfer for square-wave liquid velocity pulses in a liquid-solid column. Experiments and simulation show that, when flow reversal occurs, the average mass transfer for a pulsating flow can be significantly higher than for steady state flow at the same bulk flow rate. This increase depends mainly on the relative pulse magnitude. The influence of pulse frequency and symmetry is second-order. Apparent differences between various published studies are resolved.