Bayer Aktiengesellschaft

Claus-Peter Reisinger

Peter Fischer

Sven Michael Hansen

Johann Rechner

Ursula Jansen

Rob Eek

Kaspar Hallenberger

Carsten Hesse

Hans-Peter Wirges

Martin Friedrich

Michael Traving

Joachim Helbig

Konrad Triebeneck

A process for the preparation of an aromatic carbonate is disclosed. The process entails reacting an aromatic hydroxy compound of the formula R&#x2014;(O&#x2014;H), with carbon monoxide and oxygen, optionally in a solvent and in the presence of catalyst components, characterized in that after an initial partial charge of R&#x2014;(O&#x2014;H)to the reaction mixture, the balance thereof is subsequently metered into the reaction mixture at least once in the course of the reaction.

Process for the preparation of diaryl carbonates

The preparation of quaternary salt phenolate solutions is disclosed. The preparation entails mixing an aqueous hydroxide-containing solution with an organic phase that contains phenol and quaternary salt, distilling off the water and precipitating and filtering off the resulting salt.

Process for the preparation of quaternary salt phenolate solutions

The invention relates to a process for the removal of deposits formed in a reaction apparatus by the precipitation of solids from a liquid reaction mixture, which process is characterized in that particles of a material that is inert under the reaction conditions are introduced into the reaction apparatus, which particles, by suitable mechanical circulation of the reaction mixture, are so moved through the reactor that, during the reaction, by striking the walls or other built-in elements, they abrasively remove precipitates adhered thereto.

Method for removing deposits from chemical reactors

A process for the separation a substantially adduct-free diaryl carbonate from reaction solution is disclosed. The process entails obtaining a solution that contains diaryl carbonate, catalyst system components and an aromatic solvent, lowering the temperature of the solution, optionally in the presence of a nucleating agent, to produce a crystallization product, and washing the crystallization product with an anhydrous wash solution to remove catalyst residues and impurities.

Separation of impurities and/or valuable substances from solutions containing diaryl carbonate by solution crystallization

A process for producing diaryl carbonate is disclosed. The process entails forming a reaction mixture wherein reacting are an aromatic hydroxy compound corresponding to the formulaR&#x2014;O&#x2014;H&#x2003;&#x2003;(II),wherein R denotes a C-aromatic hydrocarbon radical, with CO and Oin the presence of a catalyst system. The catalyst system contains components a) a Group VIII B metal compound, b) at least one second metal compound, c) a bromide compound, and d) a base. The process entails introduction of one or more of components a) to d) to the reaction mixture in more than one increment in the course of the reaction.

Process for producing diaryl carbonates

Process for separating reaction mixtures and recycling quaternary salts and bases

A process for the separation and recycling of catalyst components from a chemical reaction mixture is disclosed. The process entails at least one extraction step.

Process for the separation of reaction mixtures and the recirculation of quaternary salts

A process for the preparation of a solution of a quaternary cation and an anion from a deprotonated hydroxy aromatic in an organic solvent by means of a reactive extraction of a quaternary salt in the presence of an aqueous hydroxide solution, a hydroxy aromatic and an organic solvent is disclosed. Also disclosed is a process for the recycling of a quaternary salt phenolate solution from a reaction mixture.

Process for the preparation of organic solutions

A process for the work up of a reaction mixture obtained from the preparation of diaryl carbonate by direct carbonylation of aromatic hydroxy compounds is disclosed. The process entails obtaining a reaction mixture that contains diaryl carbonate, aromatic hydroxy compound, water, base and quaternary salt, separating the mixture in a distillation apparatus having only one theoretical separation stage into a liquid phase and a gas phase and recycling the liquid phase without further work up to the reaction step of the direct carbonylation.

Method for reprocessing reaction mixtures containing diaryl carbonate

A process for the production of an aromatic carbonate is disclosed. Accordingly, an aromatic hydroxy compound is reacted with carbon monoxide and oxygen in the presence of a platinum group metal catalyst, a co-catalyst, a base, and optionally a quaternary salt as well as an inert organic solvent. The reaction is carried out under conditions whereby the inert organic solvent forms an azeotrope with the water arising during the reaction. The azeotrope is then removed from the reaction mixture.

Method for producing diaryl carbonates

A process for the work up of reaction mixtures containing diaryl carbonate, aromatic hydroxy compound, water, base and quaternary salt, which are obtained in the preparation of diaryl carbonates by direct carbonylation of aromatic hydroxy compounds, is described. In the process of the present invention an adduct of diaryl carbonate and aromatic hydroxy compound is crystallized from the reaction mixture. A distillate comprising aromatic hydroxy compound is removed from the liquid phase either prior to or after crystallization of the adduct of diaryl carbonate and aromatic hydroxy compound. The liquid phase remaining after the crystallization and distillation steps may be recycled, without further work up, back to the direct carbonylation process step by which the diaryl carbonate is initially prepared.

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Wixom, MI, United States of America

Claus-Peter Reisinger