Degussa Aktiengesellschaft

Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler

Other

Bayer Aktiengesellschaft

Degussa - Huls Ag

Ralf Goedecke

Wolfgang Nischk

Martin Liebert

Willi Hofen

Kurt Puschner

Wolfgang Plotz

Dietrich Arntz

Stephan Rautenberg

Wolfgang Boeck

Raymund Sonnenschein

Wolfgang Taugner

Joerg Sauer

Rolf Moller

Knut Ehrhardt

Uwe Kurandt

Christoph Batz-Sohn

Ulrich Deschler

Hermann Seifert

Manfred Schmidt

Hans-Joachim Hasselbach

Hans Christian Alt

Dieter Buss

Udo Zentner

J&ouml;rg M&uuml;nzenberg

Martin Körfer

Gerd Siekmann

Klaus Hentschel

Karl-Heinz R&uuml;tzel

J&ouml;rg Schmalfeld

Gundolf Hornung

Juan Garcia

Gerhard Rasig

Robert Magiera

Dieter Mewes

Volker Knapp

Hans-J&uuml;rgen Weiss

Werner Fuss

Egbert Sch&ouml;la

Udo Gropp

Tobias Groschang

Ron Stockfleth

Michael Kissner

Jürgen Stock

Rolf-Dieter M&ouml;ller

The present invention is directed to an improved process for producing methionine in which the by-product methionyl-methionine is quickly converted to the product methionine by a hydrolysis reaction. The process is performed at high temperatures (200&#xb0; C. to 280&#xb0; C.) and short residence times (20 s to 200 s) and results in an improved yield of end product methionine.

Process for producing methionine

A process is disclosed for the preparation of anhydrous sodium sulfide by heating sodium sulfide having a water content of from 38 to 40% in a contact drier in vacuo, the temperature of the solid to be dried being increased from approximately 20&deg; C. at the solid inlet to &gE;180&deg; C. at the solid outlet.

Process for the preparation of anhydrous sodium sulfide

The present invention relates to a process of recovering monomeric esters of substituted or unsubstituted acrylic acid from polymer material having corresponding structural units by depolymerization by means of a fine-grained heat-transfer medium which is maintained above the depolymerization temperature of the polymer material. In a reactor, the polymer material is brought in contact with hot, mechanically fluidized heat-transfer medium. The resulting vapors are withdrawn and condensed, where the hot heat-transfer medium is continuously supplied at one end of the reactor, and cooled heat-transfer medium is discharged at the other end.

Method for depolymerizing polymethylmethacrylate

Cyanuric chloride moldings, especially tablets and flakes, have advantages over powders in ease of handling. The moldings are produced by droplet or strip application of molten cyanuric chloride on to a surface and dissipation of the latent heat of fusion by cooling the surface or contacting the melt applied as droplets or strips with a cooling gas.

Process for the production of cyanuric chloride moldings

The invention relates to a process for the production of cyanuric chloride moldings, particularly in rod or flake form. Cyanuric chloride melt is cooled in a pressure cell equipped with a die capable of strand formation, wherein solidification takes place in the channel or channels of the die. The solidified cyanuric chloride is pressed out of the die in strand form at a temperature of 140.degree. C. or less, preferably 40 to 60.degree. C., and reduced in size as required. The process reduces the sublimation which is otherwise conventional during solidification and cooling.

A process for continuous production of methyl mercaptan by catalytic reaction of methanol and hydrogen sulfide. Significant improvements in the pretreatment of the feed gas mixture and in utilization of the heat of reaction and the heat content of the product gas mixture. The energy required to vaporize the methanol is derived partly from utilization of the heat of compression of the hydrogen sulfide gas and from the heat content of the product gas leaving the reactor. The heat of reaction is utilized to heat the feed gas mixture to the reaction temperature, with the help of an external gas heater.

Process for continuous production of methyl mercaptan

A process for separating the product gas mixture from the catalytic synthesis of methyl mercaptan. Because of improved separation of the product gas mixture into its components, less hydrogen sulfide and methyl mercaptan are lost in discharging the inert gases than in the known process. The inert gases can be burned without after-treatment of the exhaust gas. Likewise, the process water that is discharged is less contaminated with polysulfides.

Process for separating the product gas mixture from the catalytic

In a process for the continuous preparation of pure organic solutions of percarboxylic acids having 2 to 5 carbon atoms, by

Process for the preparation of percarboxylic acid solutions

Solid cyanuric chloride is recovered by a process of spraying liquid cyanuric chloride which preferably is freed from chlorine and cyanogen chloride to the maximum extent possible, the cyanuric chloride is sprayed with the aid of known spraying apparatus into a separation container and solidified by indirect cooling.

Process for the recovery of solid cyanuric chloride (A)

There is provided a process for the recovery of cyanuric chloride in solid or liquid form from the reaction mixture which results from the trimerization of cyanogen chloride wherein to recover the cyanuric chloride at will in liquid or solid form the gaseous reaction mixture is introduced into an apparatus combination consisting essentially of a stripping column and a condenser connected at the outlet side, preferably a head condenser, preferably above the stripping column, and in which the sump of the stripping column is held to the boiling temperature of the cyanuric chloride whereupon the cyanuric chloride contained in the gaseous reaction mixture depending on the regulation of the temperature at the outlet of the condenser in the range of 146.degree. to 190.degree. C. is partially condensed, after which to recover the liquid cyanuric chloride in liquid form it is removed as such at the lower end of the stripping column and is either directly or, in a given case, after an intermediate storage led to a spray tower and is sprayed whereupon the solid, fine-grained cyanuric chloride is withdrawn at the bottom of the spray tower while the residual gas leaving the condenser and still containing cyanuric chloride, which amount of cyanuric chloride is controlled by the temperature at the outlet of the condenser, is led preferably to a separating chamber and the residual cyanuric chloride is recovered there by known process.

Process for the recovery of cyanuric chloride

There is provided a process for the recovery of cyanuric chloride in solid or liquid form from the reaction mixture which results from the trimerization of cyanogen chloride wherein to recover the cyanuric chloride in liquid or solid form the gaseous reaction mixture is introduced into an apparatus combination consisting essentially of a stripping column and a condenser connected at the outlet side, preferably a head condenser, preferably above the stripping column, and in which the sump of the stripping column is held to the boiling temperature of the cyanuric chloride whereupon the cyanuric chloride contained in the gaseous reaction mixture depending on the regulation of the temperature at the outlet of the condenser in the range of 146.degree. to 190.degree. C. is partially condensed, after which to recover the liquid cyanuric chloride in liquid form it is removed as such at the lower end of the stripping column while the residual gas leaving the condenser and still containing cyanuric chloride, which amount of cyanuric chloride is controlled by the temperature at the outlet of the condenser, is led to a separating chamber and the residual cyanuric chloride is recovered there by known process.

There is provided a process for the recovery of cyanuric chloride in solid or liquid form from the reaction mixture which results from the trimerization of cyanogen chloride wherein to recover the cyanuric chloride the gaseous reaction mixture is introduced into an apparatus combination consisting essentially of a stripping column and a condenser connected at the outlet side, preferably a head condenser, preferably above the stripping column, and in which the sump of the stripping column is held to the boiling temperature of the cyanuric chloride whereupon the cyanuric chloride contained in the gaseous reaction mixture at the outlet of the condenser is cooled in the range of 146.degree. to 190.degree. C. and to recover the liquid cyanuric chloride in liquid form it is removed as such at the lower end of the stripping column and is either directly or, in a given case, after an intermediate storage led to a spray tower and is sprayed whereupon the solid, fine-grained cyanuric chloride is withdrawn at the bottom of the spray.

Solid cyanuric chloride is recovered by a process of spraying in the presence of a cooling medium liquid cyanuric chloride which preferably is freed from chlorine and cyanogen chloride, the cyanuric chloride is sprayed with the aid of known spraying apparatus into a separation container optionally with a propellant, while simultaneously with the cyanuric chloride spraying a liquid cooling medium through a second spraying apparatus separate from the first spraying apparatus, withdrawing the solidified cyanuric chloride from the separatory container and drawing off the resulting now gaseous cooling medium containing cyanuric chloride from the lower portion of the separatory container.

Process for the recovery of solid cyanuric chloride (B)

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Rodenbach, Germany

Ralf Goedecke