DE939928C - Process for the production of carbamyl chloride - Google Patents

Description

Process for the preparation of carbamyl chloride So far, carbamyl chloride has been used by reacting phosgene with ammonia or ammonium chloride at one temperature manufactured by about 4000. However, these methods are not economical Successful as large amounts of ammonium chloride are formed during the reaction or volatilize, with the result that the yield of carbamyl chloride is not is only significantly reduced, but also the plant in a relatively short time Time becomes clogged with ammonium chloride.

It is now an economical and economically feasible process for the production of carbamyl chloride that none of the above have been developed Has defects. This method consists in that phosgene and ammonia in can react in the gaseous state at a temperature of at least q.50 °. By the application of temperatures at this level is the production of ammonium chloride kept to a minimum, making the yield of carbamyl chloride remarkable grows. Since only small amounts of ammonium chloride are produced, is eliminates the problem of clogging of the plant. This result is surprising there at least phosgene at equilibrium and at q.500 'or higher temperatures is decomposed to 4q.6o / o and is normally to be expected under these conditions would be that the reaction with ammonia favors the formation of ammonium chloride and instead of a considerable increase in the yield of carbamyl chloride, this substantially would be diminished.

For a more complete understanding of the present invention, refer to refer to the following particular embodiment.

Example phosgene and gaseous ammonia were used continuously for filled for one hour in an electrically heated reaction glass tube, where they were intimately mixed and reacted at a temperature of about 50o °, wherein Phosgene and ammonia in the reaction vessel in a ratio of 3.6 mol and 2.4 MOI per hour were introduced.

The resulting gaseous product was cooled by a water-cooled Condenser passed at a temperature of about 22 °, -um the carbamyl chloride separated by condensation.

The condensed carbamyl chloride was slowly heated to igo ° '; gi g of cyanuric acid were obtained. This means a yield of 88.5% of the theoretical, based on ammonia, and proves that the yield of carbamyl chloride at least 88.5%, which was theoretical.

The reaction between phosgene and gaseous ammonia is a Temperature of at least q.500 ', preferably at a temperature of 50o to 525 °. However, higher temperatures can also be used if desired will.

Phosgene and ammonia are preferably used together in one molecular ratio converted from 1.5 moles of phosgene to 1 mole of ammonia; satisfactory results will be but also obtained. if a phosgene / ammonia molar ratio of i, i to 2 is used will. Greater or lesser mole ratios are also within the range of the invention possible, but this should be at least i.

As described above, carbamyl chloride can be obtained by heating in cyanuric acid being transformed; this is expediently done by slowly heating for about 3 hours of the carbamyl chloride in an oil bath to igo to 2o0 '°'.

Except for the production of cyanuric acid, carbamyl chloride can be used in related to the production of many other compounds of economic importance will. It can e.g. B, with aliphatic alcohols, alicyclic alcohols and oxy group-containing, aromatic compounds are converted, which is known to result in urethanes; substituted with aliphatic, alicyclic and aromatic amines are obtained Urea and ammonia in a gaseous state with a Friedel-Crafts catalyst, acid amides in a known manner.

Claims (1)

PATENT CLAIM: Process for the production of carbamyl chloride, thereby characterized that phosgene with ammonia in a gaseous state at at least q.50 °, preferably 50o Ibis 525 ', using a phosgene to ammonia molar ratio of at least i, preferably i.5. is converted. Referred publications: Ber. German chem. Ges., 33, 236, footnote 3 (igoo).