Method for purifying n-(alpha-alkoxyethyl)formamide, method for producing high-purity n-(alpha-alkoxyethyl)formamide, and device for purifying n-(alpha-alkoxyethyl)formamide
AssigneeMitsubishi Chemical Corporation
InventorsKouji TERAMOTO, Hitoshi NISHIMURA
Life of this patent
Estimating the term…
Abstract
A method for purifying an N-(α-alkoxyethyl)formamide contained in a mixture thereof with a plurality of distillation columns, the plurality of distillation columns being arranged serially, the method including condensing a distillate from the second or any later-stage distillation column to obtain a condensate and returning at least some of the condensate to the preceding distillation column.
Claims11
A method for purifying N-(α-alkoxyethyl)formamide from a mixture containing the N-(α-alkoxyethyl)formamide by using a plurality of distillation columns, wherein
- the plurality of distillation columns are disposed in series, and
- the method comprises:
- condensing an overhead efflux of a distillation column at a subsequent stage to obtain a condensate;
- and
- returning at least a part of the condensate to a distillation column at a preceding stage.
A method for producing high-purity N-(α-alkoxyethyl)formamide from a mixture containing the N-(α-alkoxyethyl)formamide, water, and an alcohol by using a plurality of distillation columns, wherein
- the plurality of distillation columns are disposed in series, and
- the method comprises:
- obtaining an overhead efflux containing an alcohol at a preceding stage and a column bottom liquid at a preceding stage in a distillation column at a preceding stage;
- introducing the column bottom liquid at a preceding stage into a distillation column at a subsequent stage;
- obtaining an overhead efflux containing water and N-(α-alkoxyethyl)formamide at a subsequent stage and a column bottom liquid containing N-(α-alkoxyethyl)formamide at a subsequent stage in the distillation column at a subsequent stage;
- condensing the overhead efflux at a subsequent stage to obtain a condensate;
- and
- returning at least a part of the condensate to the distillation column at a preceding stage.
A device for purifying N-(α-alkoxyethyl)formamide, comprising a plurality of distillation columns for distilling N-(α-alkoxyethyl)formamide-containing liquid, wherein
- the plurality of distillation columns are disposed in series, and
- the device comprises a return section for returning at least a part of a condensate of an overhead efflux of a distillation column at a subsequent stage to a distillation column at a preceding stage.
Dependencies are inferred from the claim text.