SYSTEM FOR SEPARATION OF ALKYLENE OXIDE Russian patent published in 2021 - IPC C07D301/32 C07D303/04 B01D3/32 

FIELD: chemistry.

SUBSTANCE: present invention relates to a system for separation of propylene oxide and variants of a method for separation of propylene oxide. The proposed system comprises: A) a heavy fraction rectification column capable of receiving an unpurified propylene oxide product stream and discharging: a1) a bottom heavy fraction purification product stream containing at least one additive selected from acetone, methanol, aldehydes, aldehyde derivatives, water, heavy hydrocarbons containing C₅+, or mixtures thereof; and a2) an overhead product stream of the heavy fraction rectification column containing most of the propylene oxide received with the unpurified propylene oxide product stream; and B) a first extraction distillation column capable of receiving the overhead product stream of the heavy fraction rectification column and a first selective extraction product stream containing octane as a hydrocarbon solvent, and discharging: b1) a top light fraction purification product stream containing at least one additive selected from acetaldehyde, methyl formate, methanol, water, C₃ hydrocarbons, C₄ hydrocarbons or mixtures thereof; and b2) solvent-rich bottoms streams containing most of the propylene oxide received with the overhead product stream of the heavy fraction rectification column; wherein the first extraction distillation column is additionally capable of discharging a side draw, and the system for separation of propylene oxide additionally comprises a receiving vessel capable of receiving a side draw, a depleted octane stream, as a hydrocarbon solvent, containing octane as a hydrocarbon solvent, and optionally water, promoting formation of the water phase and the organic phase, discharging the stream of the water phase purification product containing water and methanol, one or several glycols or mixtures thereof, and discharging the organic phase product stream containing propylene oxide and octane, as a hydrocarbon solvent.

EFFECT: proposed invention allows obtaining propylene oxide with a high degree of purity without product loss exceeding the normal loss.

19 cl, 5 dwg, 2 tbl, 2 ex