Abstract: A valve which is formed by a face of a valve body and the outlet area of an opening in a counterpart is disclosed. An extension dipping into the opening to ensure smooth evolution of the beginning of opening operation is known. The opening behavior achieved in this manner is not sufficient for all applications. In order to further smooth the evolution of the beginning of the opening operation, a clearance fit is provided between the extension and the opening which is interrupted by a countersink in the extension or in the opening. The countersink is formed and placed in such a manner that it comprises the counterpart of the clearance fit and at least one inclined control edge and, thereby, an adjustable choke which can be controlled in series with the valve. The countersink can take the form of a groove. Valve arrangements for compressed-air systems in motor vehicles represent a special area of application for the invention.

Abstract: The invention relates to a process for the isolation of vinyl acetate which involves not combining the bottom product of the recylced gas washings with the water-saturated vinyl acetate but rather introducing it to further multiple distillation columns from the gas mixture formed in the reaction of ethylene with acetic acid and oxygen over catalysts containing palladium or palladium compounds in the gas phase.

Abstract: The invention relates to a process for the isolation of vinyl acetate from a gas mixture containing vinyl acetate, ethyl acetate, water and carbon dioxide formed in the reaction of ethylene with acetic acid and oxygen in the gas phase over catalysts containing palladium or palladium compounds. The gas mixture leaving the reaction zone is passed into a distillation column and the gas mixture leaving the top thereof is cooled. The gas which is not condensed during the cooling is washed with acetic acid in a washing column, an acetic acid solution containing vinyl acetate being obtained. The bottom product from the distillation column is passed to a second distillation column and a side stream containing ethyl acetate is removed from an enrichment zone above the bottom thereof, all or some of the bottom product from the second distillation column, which product chiefly consists of acetic acid, being used for the wash in the washing column. The top vapor of the second distillation column is cooled.

Abstract: Process for separating water from a gas mixture, obtained in the manufacture of vinyl acetate by reacting ethylene with acetic acid and oxygen in contact with catalysts containing palladium or palladium compounds in the gaseous phase said gas mixture consisting essentially of acetic acid, vinyl acetate, water, carbon dioxide and ethylene, wherein(a) the gas mixture leaving the reaction zone is condensed to give a condensate containing the major portion of acetic acid, vinyl acetate and water and(b) an acetic acid solution containing the residual amount of vinyl acetate and water being prepared by absorption of the non-condensed gas in acetic acid, is characterized in that(c) the condensate obtained in step (a) and the solution obtained in step (b) are introduced separately from each other into the same distillation column, the feeding point of the condensate being above the feeding point of the solution, the water is distilled off at the head of said column as azeotrope together with the vinyl acetate and(d)