Patent ID: 8242314

Claim:
A method of producing purified methyl isobutyl ketone (MIBK) comprising: subjecting a feed stream containing MIBK and impurities in the form of at least water and organic compounds (including unreacted acetone) from a condensation and hydrogenation reaction of acetone to a first distillation procedure from which at least acetone is recovered and a bottom product containing MIBK and impurities is withdrawn; feeding the bottom product of the first distillation procedure to a second distillation column; withdrawing a vapour overhead product from the second distillation column; condensing said overhead product in a condensor; feeding the resulting condensed overhead product to an overhead liquid-liquid separator wherein an organic phase and an aqueous phase separate; and feeding part of the organic phase from the overhead liquid-liquid separator to the second distillation column; feeding part of the organic phase from the overhead liquid-liquid separator to a third distillation column; withdrawing a vapour overhead product from the third column which is condensed in the same condensor utilised for condensing vapour overhead product from the second distillation column; and fed to the overhead liquid-liquid separator (to which the condensed overhead product of the second distillation column is also fed); and withdrawing purified MIBK from the third distillation column.