Bergwerksverband Gmbh

Kurt Handrick

Georg Kolling

Clemens Linden

Dietrich George

Paul Kiedel

Anton Benning

Gunter Droll, Jr

Jurgen Schlegel

Fritz Mensch

Process of preparing .beta.-isopropylnaphthalene substantially free of corresponding .alpha.-isomer, in yields amounting to 90% and more by a continuous two-stage process comprising (1) alkylating naphthalene with propylene at a temperature of about 150.degree.-280.degree. C. under a pressure of 5 to 30 atm in the presence of a phosphoric acid catalyst supported on a SiO.sub.2 carrier and using a mol ratio of 1/5 to 1/20 mol propylene to 1 mol naphthalene to isopropylate 45 to 65% of the naphthalene and form a mixture of .alpha.- and .beta.-isopropylnaphthalene and then without separating off the unreacted naphthalene, (2) heating the isomeric mixture from stage (1) in the presence of a phosphoric acid catalyst supported on SiO.sub.2, to a temperature of 180.degree.-280.degree. C. under an inert gas pressure of 5 to 30 atm until no further .beta.-isopropylnaphthalene is formed and recovering said .beta.-isopropylnaphthalene from the isomerization mixture.

Preparation of .beta.-isopropylnaphthalene

A method for production of anthracene from phenanthrene is disclosed. Phenanthrene is hydrogenated at a nickel on a carrier catalyst at temperatures from about 140.degree. C. to 170.degree. C. under a pressure of from about 10 to 30 bar by gradual addition of hydrogen. The hydrogenation product is separated by distillation into sym.-octahydrophenanthrene and asym.-octahydrophenanthrene. The sym.-octahydrophenanthrene is isomerized in the presence of methylene chloride as a solvent and of aluminum chloride as a catalyst at a temperature from about -30.degree. to +5.degree. C. to sym.-octahydroanthracene. The sym.-octahydroanthracene is dehydrogenated at a chromium oxide-aluminum oxide catalyst at temperatures from about 450.degree. to 550.degree. C. to anthracene. The resulting anthracene is obtained with high yield and is very pure after a single recrystallization step.

Anthracene production from phenanthrene

In a method for the production of hydrocarbon resins based upon pyrolysates through cationic polymerization of the pyrolyzate in the presence of Friedel-Crafts catalysts and solvents at temperatures between -40.degree. and +60.degree. C., tetralin and/or tetralin derivatives are pyrolysed at 660.degree.-710.degree. C., preferably at 675.degree.-690.degree. C., in the presence of 1-10 mol, preferably 3-7 mol, vaporous water per mole tetralin or tetralin derivative with a dwell time of 1-2 seconds; the pyrolyzate is distilled to free it of high boiling (tarry) portions; and the unsaturated compounds contained in the distillate are polymerized in known manner. Styrene formed during the pyrolysis is preferably removed through distillation before the polymerization. The hydrocarbon mixture regenerated with the separation of the resins formed through polymerization are hydrogenated to tetralin and/or tetralin derivatives and again pyrolyzed.

Method for the production of hydrocarbon resins

Process for making indole by subjecting 1,2,3,4-tetrahydroquinoline to a thermal decomposition at a reaction temperature of about 650.degree. to 750.degree. C. in a reactor filled with a substantially inert material and in the presence of steam. The starting product for this process is easily available and can easily be obtained by chemical reaction and the process itself has a high yield.

Process for making indole

A process for the manufacture of anthraquinone, in which o-benzyl-toluene is oxidized with air or an oxygen-containing gas in an acetic acid solution in the presence of cobalt, manganese and bromine salts as catalysts, to which solution sufficient acetic anhydride is added to bind the reaction water, thereby keeping the acid concentration constant. The crude o-benzoyl-benzoic acid is then esterified with methanol, the methyl ester distilled from the reaction mixture and heated with concentrated sulfuric acid to yield anthraquinone in good yield and of a high degree of purity.

Catalytic oxidative process for the manufacture of anthraquinone from

A process for the manufacture of anthraquinones in which o-benzyl-toluene is first oxidized with 25 to 50 weight-% nitric acid at atmospheric pressure and moderate temperatures, and then further oxidized with a more dilute nitric acid at elevated temperatures and pressures to yield crude o-benzoyl-benzoic acid. The crude product is then esterified with methanol, the methyl ester distilled and, when necessary, recrystallized, and heated with concentrated sulfuric acid to yield anthraquinone in high yield and of a high degree of purity.

Nitric acid process for the manufacture of anthraquinone from

Processes for the continuous production of aromatic carboxylic acids by reaction of nitric acid with an aromatic compound having an oxidizable alkyl or alkoxyalkyl substitutent which comprise mixing the aromatic compound in the form of small droplets with a large volume of dilute nitric acid having a concentration between 2 and 14% by weight of nitric acid that is maintained at a superatmospheric pressure between 15 and 80 atmospheres and at a temperature between 160.degree. and 230.degree.C, which processes comprise continuously passing a reaction mixture consisting of the aromatic compound and the dilute nitric acid through a series of at least three consecutively arranged vertical reactor column in each of which the ratio of the weight of the reaction mixture containing the dilute nitric acid to the weight of the aromatic compound is continuously maintained at at least 50:1, the nitric acid concentration in each of the reactor column being continuously maintained at an originally preselected concentration by the addition of amounts of more-concentrated nitric acid while aliquot portions of the aromatic compound based upon the number of vertical reactor columns in the series are continuously introduced into each of the reactor columns, the reaction zones each being maintained at an optimal oxidation temperature between 160 and 230.degree.C for the aromatic compound that is being oxidized, and continuously passing the reaction mixture into a final reactor column that is maintained at a higher temperature than the preceding series of reactor columns, and continuously discharging the reaction mixture containing between 10 and 20% by weight of the aromatic carboxylic acid thus produced from the final reactor column.

Processes for the continuous production of aromatic carboxylic acids by

Commercial grade crude trimellitic acid anhydride containing free trimellitic acid and other impurities is purified by forming a suspension of the trimellitic acid anhydride in a mixture of acetic acid anhydride, acetic acid and benzene at a temperature of about the boiling point of the mass, the acetic acid anhydride being used in an excess up to about 200% by weight over the stoichiometric amount and the benzene being used in an amount up to 6 times the weight of the anhydride and recovering the purified trimellitic acid anhydride from the mass.

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Essen-Steele, Germany

Kurt Handrick