Abstract:
PROBLEM TO BE SOLVED: To provide a process for producing methionine and a salt thereof. SOLUTION: The methionine is produced by passing 3-methylmercaptopropionaldehyde, hydrogen cyanide, ammonia and carbon dioxide through steps of synthesis, hydrolysis and liberation. The nearly quantitatively obtained methionine has slight discoloration and good storage stability. Continuous production can be carried out in a large-scale apparatus by the process. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
OXAMIDE IS FORMED IN GOOD YIELDS UNDER ANHYDROUS CONDITIONS EMPLOYING (1) CYANOGEN, (2) A CARBOXYLIC ACID AND (3) A CARBOXYLIC ACID HALIDE OR HYDROGEN HALIDE. PREFERABLY SUPERATMOSPHERIC PRESSURE IS EMPLOYED.
Abstract:
In situ regeneration of noble metal catalysts for the synthesis of hydrogen peroxide by the anthraquinone process is provided by employing as the working solution coming from the extraction or desorption step and being introduced into the hydrogenation step a solution which contains at least 250 mg/liter of hydrogen peroxide, to thereby completely regenerate the noble metal catalyst by full capacity of the hydrogenation step.
Abstract:
Pure acetonitrile is recovered from aqueous acetonitrile by extracting with an organic solvent which has little miscibility with water, boils higher than acetonitrile and does not form an azeotrope with acetonitrile. The portion of the extract boiling up to 76*C is distilled off. The remaining acetonitrile containing more difficulty volatile portion is freed from the residual water by addition of an entraining agent and recovering the pure acetonitrile by a fractional distillation.
Abstract:
Malonodinitrile produced from cyanogen halide and acetonitrile and containing fumarodinitrile as an impurity is purified and stabilized by recrystallizing from an aliphatic alcohol or dialkyl ether in the presence of benzonitrile.
Abstract:
CYANOGEN IS PREPARED BY REACTING HYDROGEN CYANIDE AND CHLORINE IN THE PRESENCE OF A SURFACE ACTIVE CATALYST. THE PRODUCT STILL CONTAINING HYDROGEN CYANIDE IS TREATED WITH 1 TO 1.1 MOLE OF CHLORINE PER MOLE OF HYDROGEN CYANIDE REMAINING AT 195 TO 800* C. FOR 10 TO 0.01 SECOND AND IN THE PRESENCE OF THE SURFACE ACTIVE CATALYST, PREFERABLY ACTIVATED CARBON.
Abstract:
Die vorliegende Erfindung betrifft ein Verfahren zur Vakuumdestillation mindestens einer organischen Verbindung mittels einer eine Absorptionsflüssigkeit enthaltenden Vakuumeinrichtung (8), wobei die Absorptionsflüssigkeit von der zu destillierenden organischen Flüssigkeit verschieden ist und mit ihr eine Additionsverbindung bildet und/oder die Absorptionsflüssigkeit mit der zu destillierenden organischen Verbindung identisch ist, sowie die Verwendung von Verbindungen der allgemeinen Formel (I) R-CHO als Schmiermittel in Flüssigkeitsringpumpen und Flüssigkeitsringpumpen, die erfindungsgemäße Absorptionsflüssigkeiten als Ringflüssigkeit enthalten oder aus ihr bestehen.
Abstract:
The present invention provides a process for recovering methionine and potassium from recycled solutions of the potassium carbonate-methionine process, which comprises increasing the concentration of the mother liquors obtained after the separation of the methionine and carbonating said concentrated mother liquors while cooling.