Acrylonitrile recovery process

Abstract

The process of the present invention comprises transporting a reactor effluent containing acrylonitrile/methacrylonitrile to a first column (quench) where the reactor effluent is cooled with a first aqueous stream, transporting the cooled effluent into an indirect contact cooler to condensed at least some of the cooled effluent to form a condensate comprising water and acrylonitrile/methacrylonitrile, transporting the remaining cooled gaseous effluent containing acrylonitrile/methacrylonitrile into a second column (absorber) where the cooled effluent is contacted with a second aqueous stream to absorb substantially all of the remaining acrylonitrile/methacrylonitrile into the second aqueous stream, transporting the second aqueous stream containing the acrylonitrile/methacrylonitrile to a first distillation column (recovery column) for separation of the crude acrylonitrile/methacrylonitrile from the second aqueous stream, and transporting the separated crude acrylonitrile/methacrylonitrile to a second distillation column (heads column) to remove at least some impurities from the crude acrylonitrile/methacrylonitrile, and transporting the partially purified acrylonitrile/methacrylonitrile to a third distillation column (product column) to further purify the acrylonitrile/methacrylonitrile, and recovering the purified acrylonitrile/methacrylonitrile, wherein the improvement comprises transporting the condensate formed in the indirect contact cooler to a decanter where the condensate is separated into an organic phase comprising acrylonitrile/methacrylonitrile, an aqueous phase and a vapor phase, and the organic phase is introduced into the recovery column without passing through the absorber column.