There is disclosed an azeotropic distillation process for separating toluene from methyl isobutyl ketone (MIBK) in a spent liquor mixture. A toluene azeotrope former, preferably methanol, is added to the liquor in an amount sufficient to form an azeotrope with all of the toluene present in the mixture. The methanol is added in an amount of at least about 2.62, typically an excess amount of about 3.4 to about 6.3 parts by weight of methanol per 1.0 part by weight of toluene. The resulting azeotrope of methanol and toluene is then separated by distillation from the MIBK. The methanol may be subsequently recovered from the toluene by extraction with water. Other toluene azeotrope formers may be utilized.