is the ester in the same phase as the ethanol-water mixture?
if the ester is in the same phase, use diethyl ether to extract the ester. the ether layer can be obtained by using a seperating funnel. You may have ethanol in your ether layer if ethnaol was not the limiting reagent.
the rotary evaporator will help to remove diethyl ether from the ether-ester mixture.