SE123750C1

SE123750C1 -

Info

Publication number: SE123750C1
Authority: SE
Publication date: 1948-01-01

Description

KLASS 12o:14 BESKRIVNING OFFENTLIGGJORD AV KUNGL. PATENT- OCH REGISTRERINGSVERKET BEVILJAT DEN 11 NOVEMBER 1948 PATENTTID FRAN DEN 21 JUNI 1944 PUBLICERAT DEN 11 JANUAR! 1949 Ans. den "/, 1944, nr 5161/1944. CLASS 12o: 14 DESCRIPTION PUBLISHED BY KUNGL. PATENT AND REGISTRATION AGENCY GRANTED ON NOVEMBER 11, 1948 PATENT PERIOD FROM JUNE 21, 1944 PUBLISHED ON JANUARY 11! 1949 Ans. den "/, 1944, No. 5161/1944.

I. G. FARBENINDUSTRIE AKTIENGESELLSCHAFT, FRANKFURT AM MAIN, TYSKLAND. I. G. COLOR INDUSTRY AKTIENGESELLSCHAFT, FRANKFURT AM MAIN, GERMANY.

Kitt att framstalla trimesinsyra. Putty to produce trimesic acid.

Uppfinaare: W. Berndt. Inventor: W. Berndt.

Prioritel board fran den 10 juli, 1943 (7'yska Hittills ãr ,endast ett satt att framstalla trimesinsyra kant genom dekarboxylering av hogre bensolpolykarbonsyror. Priority board from July 10, 1943 (7'Yska So far this year, only one set to produce trimesic acid edge by decarboxylation of higher benzene polycarboxylic acids.

Enligt detta upphettas mellitsyra starkt med glycerin, varvid kolsyra avspaltas och trimesinsyra uppkommer. Uppgifter over erhallet utbyte fattas. According to this, middle acid is strongly heated with glycerin, whereby carbon dioxide is cleaved and trimesic acid is formed. Information on the received exchange is taken.

Man har nu funnit .att man pfi ett enkelt satt kan erhalla trimesinsyra genom dekarboxylering av mellitsyra om man utfor dekarboxyleringen i -vattenlosning vid temperaturer mellan ungefar 200 och 30. Formodligen heron den gynnsamma verkan av vattnet darpa, att en fullstandig eller delvis uppkomst air anhydrider air intilliggande karboxylgrupper undvikes. Vid franvaro av katal3rtiskt verkande tillsatser valjas temperaturer melIan 250 och 30, foretradesvis 260-300°. Om man utfor operationen i narvaro av katalytiskt verkande dmnen (som exempel bland ,ett Herta' sadana ma hdr endast namnas koppar eller kopparforeningar), sa kan bildning air trimesinsyra uppkomma redan under namnda temperaturer, t. ex. redan mellan 200 och 250°. It has now been found that trimesic acid can be obtained in a simple manner by decarboxylation of middle acid if the decarboxylation is carried out in aqueous solution at temperatures between about 200 and 30. Presumably the beneficial effect of the water is that a complete or partial formation of air anhydrides air adjacent carboxyl groups are avoided. In the absence of catalytic additives, temperatures are chosen between 250 and 30, preferably 260-300 °. If the operation is carried out in the presence of catalytically active substances (as an example among, a Herta 'such may only be called copper or copper compounds), then the formation of air trimesic acid can occur already under the mentioned temperatures, e.g. already between 200 and 250 °.

Sa.V5.1 ren som rã mellitsyra, t. ex. sadan den erhalles vid oxidation av kol, hail komma till anvandning. Vid anvandning av râ mellitsyra dr del dock lampligt att anyanda en sadan med mEdligast ringa halt ay oorganiska bestandsdelar. Sa.V5.1 pure as crude middle acid, e.g. so it is obtained in the oxidation of carbon, hail come into use. When using crude middle acid, however, it is advisable to use one with the lowest content of inorganic constituents.

Forfarandet kan aven utforas kontinuerligt med anvandning av kanda medel. The process can also be carried out continuously using known agents.

Exempel: 3 viktsdelar mellitsyra upphettas tillsammans med 5 viktsdelar vatten i ett tryckkfirl, som lampligen bestar ay korrosionsbestdndigt material eller an infodrat med sadant, till 280-290°. Till foljd av den hoga temperaturen och den starka kolsyrebildningen upptrada avsevarda tryck. Reaktionen är avslutad nar ingen avsevard tryckstegring Yang-re kan konstateras. Efter avkylning upparbetas karlets innehall pa trimesinsyra. Delta gar sa mycket ldttare ju renare mellitsyra man anyander. Vid anyandning ay en ren eller nastan ren mellitsyra behandlas reaktionsprodukten i varme med nagot avfdrgningskol oeh ur den eventuellt nagot indunstade eller med saltsyra forsatta losningen utkristalliserar den. i hold tamligen svarldsliga trimesinsyran. Denna uppvisar hog grad ay renhet, men kan eventuellt om sã erfordras ytterligare renas genom ytterligare ornkristallisering eller sublimering i vakuum, t. ex. vid 280-320°. Utbytet fir beroende ay betingelserna och renheten hos utgangsmaterialet. I gynnsammaste fall är utbytet ndstan kvantitativt. Example: 3 parts by weight of middle acid are heated together with 5 parts by weight of water in a pressure vessel, which suitably consists of corrosion-resistant material or lined with such, to 280-290 °. Due to the high temperature and the strong carbon dioxide formation, considerable pressures occurred. The reaction is complete when no significant increase in Yang-re pressure can be observed. After cooling, the contents of the vessel are worked up on trimesic acid. Delta goes so much lighter the purer middle acid you anyander. Upon inhalation of a pure or almost pure intermediate acid, the reaction product is treated in heat with some carbon monoxide and crystallizes out of any solution which has been slightly evaporated or hydrochloric acid. in hold rather blackish trimesic acid. This exhibits a high degree of purity, but may optionally be further purified if necessary by further crystallization or sublimation in vacuo, e.g. at 280-320 °. The yield depends on the conditions and purity of the starting material. In the most favorable case, the yield is almost quantitative.

Claims

1. Patent claim: My preparation of trimesic acid by decarboxylation of middle acid, which may optionally be present in admixture with other compounds, may be characterized in that the decarboxylation is carried out in aqueous solution at temperatures between 200-3 °. Stockholm 1948. Kungl, Boktr. P. A. Norstedt & Nnor 480089