Evonik Operations Gmbh

Evonik Degussa Gmbh

Thyssenkrupp Industrial Solutions Ag

David Bolz

Holger Wiederhold

Bernd Jaeger

Hans-Jurgen Kohle

Georg Friedrich Thiele

Patrik Glatz

Willi Hofen

Johannes Kowoll

Norbert Ullrich

Wolfgang Wöll

Hans-Jürgen Köhle

Bärbel Kolbe

Jürgen Glenneberg

Marc Brendel

Peter Porscha

Sebastian Imm

Manfred Bärz

Niels Bredemeyer

Jürgen Schemel

Marina Lazar

Maik Bernhard

Michael Dopfer

Dana Pfenning

Jürgen Berje

Patrick Glatz

1,2-propanediol is prepared by a method involving reacting propene with hydrogen peroxide at 50 to 110° C. in the presence of a catalyst mixture, containing a phase transfer catalyst and a polytungstophosphate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase. The method then involves separating the reaction mixture into an aqueous phase containing 1,2-propanediol and an organic phase; recycling at least part of the separated organic phase to the reaction; and recovering 1,2 propanediol from the aqueous phase. The method further involves reacting a tungstate with hydrogen peroxide and phosphoric acid at 5 to 40° C., in the presence of the phase transfer catalyst, in a liquid mixture containing an aqueous and an organic phase, followed by passing at least a part of the resulting organic phase containing the polytungstophosphate and phase transfer catalyst to the initial reaction.

Method for the preparation of 1,2-propanediol

A method for preparing 1,2-propanediol involves continuously reacting propene with hydrogen peroxide in the presence of a catalyst mixture, containing a quaternary ammonium salt and a polytungstophosphate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase containing an alkylaromatic hydrocarbon solvent. The method then involves withdrawing the liquid reaction mixture from the reaction and adding a water-soluble sulfate salt or sulfuric acid to provide a mixture containing from 500 to 10,000 mg/kg of sulfate ions in the aqueous phase. The method further involves separating the mixture obtained into an aqueous phase (P) containing 1,2-propanediol and an organic phase (P), recycling at least a part of the organic phase (P) to the reaction, and recovering 1,2-propanediol from the aqueous phase (P). The method allows for extended operation of the reaction with little loss of tungsten and phase transfer catalyst.

A method for preparing 1,2-propanediol involves reacting propene with hydrogen peroxide in the presence of a catalyst mixture containing a phase transfer catalyst and a heteropolytungstate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase. The process then involves separating the reaction mixture into an aqueous phase (P) containing 1,2-propanediol and an organic phase (P); recycling at least part of the separated organic phase (P) to the reaction; and recovering 1,2 propanediol from the separated aqueous phase (P). In the recovery, 1,2-propanediol is separated from the aqueous phase (P) by distillation and the apparent pH of the separated aqueous phase (P) is adjusted to at least 9 prior to the distillation to reduce the content of formic acid and acetic acid in the recovered 1,2-propanediol.

A method for preparing 1,2-propanediol involves reacting propene with hydrogen peroxide in the presence of a catalyst mixture, containing a phase transfer catalyst and a heteropolytungstate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase. The method then involves separating the reaction mixture into an aqueous phase (P), containing 1,2-propanediol and phosphoric acid esters of 1,2-propanediol, and an organic phase (P). The method further involves recycling at least part of the separated organic phase (P) to the reaction; heating at least a part of the separated aqueous phase (P) to a temperature of more than 140° C. at a pressure sufficient to maintain at least part of the aqueous phase as a liquid; and recovering 1,2-propanediol from the heated aqueous phase. The heating cleaves phosphoric acid esters of 1,2-propanediol into 1,2-propanediol and phosphoric acid.

A process for preparing 1,2-propanediol involves dehydrogenating propane to provide a product stream containing propane, propene, and hydrogen; and separating the product stream into a stream containing essentially hydrogen, a stream enriched in propane, and a stream enriched in propene. The process then involves reacting the stream containing essentially hydrogen with oxygen to provide a stream containing hydrogen peroxide; and reacting the stream enriched in propene with the stream containing hydrogen peroxide in the presence of a catalyst mixture, containing a phase transfer catalyst and a heteropolytungstate, in a reaction mixture with two liquid phases. The process further involves separating the reaction mixture of the propene oxidation into an aqueous phase and an organic phase, recycling the organic phase to the propene oxidation, and separating 1,2-propanediol from the aqueous phase.

Process for preparing 1,2-propanediol from propane

The integrated process comprises a step a) of dehydrogenating propane providing a stream S1 comprising propane and propene; a step b) of separating stream S1 in at least one rectification column, providing an overhead product stream S2 comprising more than 99% by weight propene, a side stream S3 comprising from 90 to 98% by weight propene and a bottoms product stream S4 enriched in propane; a step c) of reacting propene with hydrogen peroxide in the presence of an epoxidation catalyst using propene in molar excess; and a step d) of separating non-reacted propene and propene oxide from the reaction mixture of step c) providing a propene oxide product and a stream S5 comprising propene and propane; wherein stream S3 is passed to step c), stream S5 is recycled to step b) and stream S4 is recycled to step a).

Integrated process for making propene and propene oxide from propane

The process for preparing 1,2-propanediol from propene and hydrogen peroxide comprises the steps of

Method for producing propylene glycol from propene and hydrogen peroxide

Propene is continuously reacted with hydrogen peroxide in a tube bundle reactor comprising a multitude of parallel reaction tubes in the presence of a titanium silicalite catalyst arranged as a fixed bed in the reaction tubes. A cooling jacket encloses the reaction tubes, which has a feed point for cooling medium near the entry of the reaction tubes, a withdrawal point for cooling medium near the end of the reaction tubes and at least one additional withdrawal point upstream of the withdrawal point near the end of the reaction tubes. Cooling medium is fed to the feed point for cooling medium, a part of the cooling medium is withdrawn at the at least one additional withdrawal point and the remainder exits at the withdrawal point near the end of the reaction tubes.

Process and reactor for the epoxidation of propene

An integrated process for making propene oxide and an alkyl tert-butyl ether comprises dehydrogenating a feed stream comprising iso-butane to provide a stream comprising iso-butene and hydrogen and separating this stream into a stream consisting essentially of hydrogen and a stream comprising iso-butene; reacting a part or all of the stream comprising iso-butene with an alkanol in the presence of a solid acid catalyst to provide an alkyl tert-butyl ether; reacting a part or all of the stream consisting essentially of hydrogen with oxygen, providing a stream comprising hydrogen peroxide; and reacting a part or all of the stream comprising hydrogen peroxide with propene in the presence of an epoxidation catalyst to provide propene oxide.

Integrated process for making propene oxide and an alkyl tert-butyl ether

An integrated process for making propene oxide and an alkyl tert-butyl ether comprises dehydrogenating a feed stream comprising propane and iso-butane to provide a stream comprising propene, iso-butene and hydrogen; separating this stream into a stream consisting essentially of hydrogen and a stream comprising propene and iso-butene; separating the stream comprising propene and iso-butene into a stream comprising propene and a stream comprising iso-butene; reacting a part or all of the stream comprising iso-butene with an alkanol in the presence of a solid acid catalyst to provide an alkyl tert-butyl ether; and reacting a part or all of the stream comprising propene with hydrogen peroxide in the presence of an epoxidation catalyst to provide propene oxide.

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Frankfurt-am-Main, Germany

David Bolz