Abstract: The repulsive extraction is proposed to separate butanol and acetone from water. In order to reduce energy consumption in the separation, NaAc,MgCl 2,Na 2CO 3 and other salts are added in the process to form composite extractant, which can obviously change the mutual solubility of butanol acetone water system at room temperature. The composite extractant can greatly increase the distribution coeffecient and selectivity coefficient. The effect of the operation parameter on separation is further studied. Preliminary heat balance shows that the new separating method can save 30.4% energy compared with the traditional method.

Key words: butanol, acetone, extraction, separation, save energy