The control behavior of a nine inch diameter eight tray bubble cap column separating a methanol‐water mixture has been studied using feedback, feedforward and combined feedforward‐feedback control. Top product composition was controlled by manipulation of the reflux rate to compensate for feed flow disturbances. Pulse testing was used to determine the process transfer functions. Gain, gain plus time delay and gain plus time lag feedforward control were implemented by means of an IBM 1800 digital computer. Combined feedforward‐feedback control, using gain and gain plus time lag feedforward control action, was also studied. The improved column control behavior is compared with results obtained using only feedback control.