Degussa Aktiengesellschaft

Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler

Degussa - Huls Ag

Hermann Schmitt

Klaus Huthmacher

Steffen Krill

Werner Heimberger

Klaus Hutchmacher

Gerd Schreyer

Herbert Tanner

Stephan Kretz

Hans-Joachim Hasselbach

Frank Hubner

Bernd Drapal

Rainer Hahn

Friedhelm Geiger

A process for the preparation of 3,5,5-trimethylcyclohexa-3-en-1-one (&bgr;-isophorone) by isomerization of 3,5,5-trimethylcyclohexa-2-en-1-one (&agr;-isophorone) in the liquid phase in the presence of a salt-like or organometallic catalyst. By using catalytic quantities of alkali-metal salts or alkaline-earth salts and/or their organometallic compounds, and without addition of a further auxiliary substance, the space-time yield in the preparation of &bgr;-isophorone is high. &bgr;-Isophorone is particularly suitable as an intermediate product for the preparation of ketoisophorone.

Process for the preparation of 3,5,5-trimethylcyclohexa-3-en-1-one (&bgr;-isophorone) by isomerization of 3,5,5- trimethylcyclohexa-2-en-1-one (&agr;-isophorone)

The invention relates to an improved method for the production of 2,3,5-trimethylhydroquinone by rearranging 4-oxo-isophorone (keto-isophorone, 3,5,5-trimethylcyclohex-2-en[e]-1,4-dione) to a trimethylhydroquinone diester and by its subsequent saponification. ##STR1##

Method for the production of trimethylhydroquinone

The reductive amination of 1,3,3-trimethyl-5-oxocyclohexane carbonitrile (IPN) with ammonia and hydrogen in the presence of nickel- or cobalt Raney catalysts to 3-aminomethyl-3, 5,5-trimethyl-cyclohexyl amine is achieved in a single stage with a good yield and requires no pressure distillation if a co-catalyst selected from the group consisting of salts of nickel, cobalt, yttrium, lanthanum and cerium is used in an amount of 0.01 to 0.5 mole per mole Raney catalyst.

Method of preparing 3-aminomethyl-3,5,5-trimethyl cyclohexyl amine

The invention relates to bis(3-cyano-3,5,5-trimethylcyclohexylidene)-azine (=IPN-azine), a method of its preparation by reacting 1,3,3-trimethyl-5-oxocyclohexane carbonitrile (=IPN) with a source for hydrazine in a molar ratio of essentially 2 to 1 in the presence of a solvent and to a method for the further processing of the IPN-azine to 3-(aminomethyl)-3,5,5-trimethylcyclohexyl amine (isophorone diamine=IPDA) by means of a hydrogenating azine splitting with hydrogen in the presence of an organic solvent, ammonia and of a catalytic system from the series (a) of a cobalt- or nickel-containing Raney catalyst and of a cocatalyst from the series of salts of the elements aluminum, cobalt, nickel, yttrium, lanthanum, cerium, Ru, Rh, Pd, Ir and Pt or of carrier-supported noble metals from the series Ru, Rh, Pd, Ir, Pt or b) of a carrier-supported Ru-, Pd- or Pt catalyst at a pressure of 3 to 30 MPa and a temperature of 50.degree. to 150.degree. C. The method of the invention concerning IPN-azine makes it possible to obtain IPDA from IPN in high yield and purity and avoids disadvantages of the previously known reductive amination of IPN.

Bis(3-cyano-3,5,5-trimethyl-cyclohexylidene)-azine, a method of its

Hydrogen cyanide is added to isophorone for the preparation of 1,3,3-trimethyl-5-oxo-carbonitrile in the presence of lithium hydroxide in an amount in a range of 0.005 to 5 mole % at 100.degree. to 160.degree. C. The yield is higher and the space-time yield is better than was possible when using other alkaline acting alkali compounds.

Method of preparing 1,3,3-trimethyl-5-oxo-cyclohexane carbonitrile

There is provided a process for the purification of ammonia or ammonium salt containing waste waters using alkali metal or alkaline earth metal hypochlorites comprising adjusting the waste water to an initial pH of 8-10.5 with an alkaline material and then treating the waste water with an alkali metal or alkaline earth metal hypochlorite in an amount practically equivalent to the ammonia or ammonium salt, in a given case while lowering the pH during the evolution of nitrogen by additional neutralization of this pH to about 6-8 whereupon only after the end of the evolution of nitrogen the pH of the waste water, if it deviates from 7, is adjusted to the neutral region in known manner. The initial pH is preferably adjusted with the help of an alkali or alkaline earth hydroxide, most preferably it is adjusted to a pH of 8-9 with the help of a buffer salt.

Process for the purification of waste water containing ammonia and

Cyanogen chloride is purified and the service life of activated carbon is increased in the subsequent trimerization of the cyanogen chloride to cyanuric chloride by process comprising reacting hydrogen cyanide with chlorine, in a given case in the presence of cyanogen chloride produced in the presence of water, which in a given case contains chlorine. The improvement comprises passing the cyanogen chloride over granular gamma aluminum oxide with an alkali metal or in a given case an alkaline earth metal content of 0 to 3 weight % at 20.degree.-100.degree.C., preferably 30.degree.-60.degree.C.

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Rodenbach, Germany

Hermann Schmitt