PROCESS FOR PREPARING METHYL ISOBUTYL KETONE

The present invention relates to a process for preparing methyl isobutyl ketone starting from acetone, wherein a raw product stream of methyl isobutyl ketone, for preparation, is firstly fed to at least one first distillation column (23) and the product from the sump of this first distillation column (23) is then fed to a liquid-liquid separation device (27), in which water is separated off from an organic phase. In accordance with the invention the water phase of the liquid-liquid separation device (27) is fed to at least one further separation device (35) in which a portion of the acetone contained in the water phase is separated off from the process stream. It is possible to recover acetone from the wastewater stream as a result of the further preparation step in this further separation device (35). This leads to an optimisation of the process for preparing methyl isobutyl ketone that makes it possible to further reduce the acetone loss.