DE1277233B - Process for the production of alcohols or amino alcohols - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

German class:

Number:
File number:
Registration date:
Display day:

C07c

BOIj

12 ο -5/03

12q-32/01

12 g -11 (K

P 12 77 233.7-42 (C 31415)

November 14, 1963

September 12, 1968

The invention relates to a process by which lactones or lactams are reacted with Hydrogen at elevated temperature and at normal pressure to the corresponding alcohols or Amino alcohols are hydrogenated.

The production of polyhydric alcohols by hydrogenation of corresponding oxygen ring compounds or of esters of carboxylic acids or dicarboxylic acids is known from numerous publications. There are already the A wide variety of catalyst systems have been proposed. Typical copper chromite catalysts are an example of this.

The present invention is based on the finding that with a very specific catalyst improved results in the hydrogenation reaction can be obtained on the basis of copper chromite.

The invention accordingly relates to a process for the production of alcohols or Amino alcohols by hydrogenation of esters, lactones or lactams with hydrogen at increased Temperatures and pressures in the presence of hydrogenation catalysts, which is characterized by that a catalyst is used, the barium-added copper chromite on an inactive aluminum oxide carrier contains.

The particular catalysts of the invention are very effective. So z. B. with copper chromite, stabilized with barium oxide, conversions of 80% or more can be achieved. The catalysts are advantageous not only for the hydrogenation of the cyclic compounds mentioned, but also for the hydrogenation of acyclic esters to produce the alcohols that make up the acid component of the Esters correspond. The alcohols formed at the same time correspond to the alcohol component of the ester. The catalysts of the invention have never been proposed for this reaction to date.

The acyl portion of the compounds to be hydrogenated can be derived from a mono- or polybasic aliphatic saturated acid having 12 or fewer carbon atoms. In the acyclic esters, the alcohol component can be derived from a mono- or polyhydric aliphatic alcohol which contains the same or a different number of carbon atoms than the acyl portion of the molecule, e.g. B. 1,6-hexanediol, n-hexanol, cyclohexanol, 1,4-butanediol, n-octanol or the like. Suitable are lactones or lactams with up to 8 carbon atoms, preferably with at least 4 carbon atoms, ζ. B. butyrolactone, y-valerolactone, ε-caprolactone and ε-caprolactam. The lactone ring can be given processes for the production of alcohols or
Amino alcohols

Applicant:

Celanese Corporation of America,

New York, N.Y. (V. St. A.)

Representative:

Dr.-Ing. A. v. Kreisler, Dr.-Ing. K. Schönwald
and Dr.-Ing. Th. Meyer, patent attorneys,
5000 Cologne 1, Deichmannhaus

Named as inventor:
Coy Huborn Hood,
Hopkins Wade Tatum,
Clarkwood, Tex. (V. St. A.)

Claimed priority:
V. St. v. America November 16, 1962
(238 277)

if they contain substituents that do not take up hydrogen. The invention includes hydrogenation of esters with hydroxyl groups on the acyl portion of the molecule, e.g. B. 1,6-hexanediol, mono- or di- (oxycaproate), and amino esters, e.g. B. Hexyl (6-amino) caproate.

The process is carried out by combining the compounds to be hydrogenated and hydrogen in one Reactor are introduced which is operated at an elevated temperature, e.g. B. 200 to 350 ° C, preferably 250 to 290 ° C, and at overpressure, e.g. B. 70 to 840 atmospheres, preferably 260 to 350 atmospheres, is held. the Catalysts based on copper chromite are applied to inactive aluminum oxide as a carrier, where the aluminum oxide is preferably between about 1000 ° C and the melting point of the Alumina calcined alumina hydrate is used. The hydrogenation can be with or without Solvents that can be used with the connecting agents to be hydrogenated are dioxane, butanol and ethanol. That Solvent can be mixed with the compound to be hydrogenated, e.g. B. at 100 to 150 ° C, whereupon the mixture is heated in a closed vessel, for example to 190 ° C and then in the Hydrogenation reactor is introduced. The ratio of solvent to ester can, for example, from 1: 4 to

809 600/577

2: 1 and is preferably about 1: 1. These preheat temperatures are used regardless of whether a solvent is used or not, the reaction mass is usually raised to a temperature up to about by the heat of reaction Brought 245 to 250 ° C, while the pressure required for the hydrogenation by the feed Hydrogen is generated.

The hydrogenation reaction can be carried out in a fixed, flooded catalyst bed, or a suspended one Catalyst bed or a trickle bed can be carried out. At a fixed, flooded In the catalyst bed, the catalyst particles are in granular or otherwise proportionate form large form, while the compound to be hydrogenated and any solvent used a Form a continuous liquid phase that completely floods the catalyst. With a firmly arranged The catalyst particles are generally granulated and arranged relatively firmly in a trickle bed, while the compound to be hydrogenated and any solvent used from above the Bed are fed and form a relatively disperse phase. A suspended catalyst bed consists of powdered catalyst with a particle size of, for example, about 60 μ or less that is suspended in the liquid phase. The liquid is usually supplied at the Suspension bed from below, with trickle bed from above and with flooded catalyst bed from above or below, the latter being preferred. In any case, the gas phase enters the catalyst bed from below introduced.

When using hydrogenation catalysts based on copper, a service life of the catalyst be reached that are more than 100 kg, e.g. B. corresponds to 200 kg of hydrogenation product per kh of catalyst.

In the following example, the quantities given are based on weight, unless otherwise stated.

example

A mixture of esters, which was obtained from the partial oxidation of cyclohexane with 1,6-hexanediol in the esterification of acids, is set to Vs "or ^{1 at 300 ° C. and about 280 atm. Over a copper-barium-chromite catalyst} A "aluminum oxide headed. The catalyst lies in one. Trickle bed reactor, into which the ester mixture is passed at a rate of 6.0 lbs / hr / ft ³ . The catalyst has been produced in a manner known per se, the support being mixed with a 30 weight percent aqueous solution of the nitrates or acetates of the metals in the required proportions

ao conditions and then the metals are precipitated in the form of their hydroxides by immersing the impregnated carrier in aqueous sodium hydroxide solution. After the carrier has been practically washed free of sodium salts and its alkali content, it is dried. The hydroxides are then calcined to the oxides by the catalyst treated is maintained for 4 to 6 hours at 500 ⁰ C. If a higher loading of the carrier with the metals is desired, this impregnation treatment can be repeated. will. Maximum amounts of 5 percent by weight are preferred, however, since higher amounts lead to erosion of the metal used. The catalyst is then used slowly with hydrogen in the reactor

heated. -

attempt CuO Ka alysator mixture
Cr ₂ O ₃ I. BaO Aluminum oxide carrier converted
ter ester End product
easier
proportion of water Weight percent 1 1.5 0.8 inactive 98 Weight percent 1.7 2 1.5 0.8 inactive 97 17th 2.0 3 5 2 active 90 15th 4.0 4th 2 2 active 44 48 2.8 5 9 1 none - 90 46 3.0 2.0 41 2.0 5 ■ 5 9

In a further series test, a corresponding catalyst is used on inert aluminum oxide used. With the same starting material, 86% conversion is achieved with only 2.2% lighter proportions and a negligible amount of water obtained while using active alumina only results in a conversion of 18% with no less than 39% light proportions.

Claims (2)

Patent claims: 1. Process for the preparation of alcohols or amino alcohols by hydrogenation of Esters, lactones or lactams with hydrogen at elevated temperatures and pressures in Presence of hydrogenation catalysts, thereby characterized in that a catalyst is used, the barium-added copper chromite on an inactive aluminum oxide carrier. 2. The method according to claim 1, characterized in that the ester is acyl esters of alcohols or amino alcohols can be used. Considered publications:
German Auslegeschrift No. 1034165,
1023 750, 1008273; U.S. Patent Nos. 2,686,817, 2,750,429;
Angewandte Chemie, 67 (1955), p. 321;
Kunststoff Rundschau, 1958, pp. 340, 341. S09 600/577 9.68 © Bundesdruckerei Berlin