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AssigneesBayer Aktiengesellschaft, Deutsche Gold- und Silber-Scheideanstal vormals Roessler
InventorsWilli Hofen, Rolf Wirthwein, Karl-Hermann Reissinger, Jorg Krekel
Estimating the term…
Process for separating a solution, which essentially contains propylene oxide, propylene, a carboxylic acid containing 1 to 4 carbon atoms and benzene, by distillation. The solution is fed to a first distillation stage in which propylene, propylene oxide and an amount of the benzene contained in the solution such that the top product from this first distillation contains 20 to 70% by weight of benzene are distilled off over the top at a pressure of 1.0 to 2.5 bars, and in which the carboxylic acid and the remaining benzene are obtained as the sump product. The top product from the first distillation is fed to a second distillation column in which propylene and possibly present small fractions of components which boil lower than propylene oxide are distilled off over the top and a sump product which essentially consists of propylene oxide and benzene is obtained and part of this is returned as reflux to the first distillation column.
Process for separating a solution comprising propylene oxide, propylene, carboxylic acid containing 1-4 carbon atoms and benzene, by distillation, comprising distilling the solution in a first distillation stage to provide an overhead product rich in propylene and propylene oxide and containing 20-70% by weight of benzene and a bottoms product rich in carboxylic acid and containing the remaining benzene, at a pressure of 1.0-2.5 bars, and distilling said overhead product in a second distillation stage to provide an overhead product comprising propylene and a bottoms product comprising benzene rich in propylene oxide and recycling part of the bottoms of the second distillation stage to the first distillation as reflux for the first distillation stage.
Process of 2, wherein the pressure of the first distillation stage is 1.2-2.0 bars, and the pressure of the second distillation stage is 4-15 bars.
Dependencies are inferred from the claim text.