AU604961B2 - A process for the production of ether carboxylic acids - Google Patents

Description

Iu: Ifb COMMISSIONER OF PATENTS OUR REF: 55400 S&F CODE: 55370 72 2'O 0 s 5845/2

I,

S F Ref: 55400 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class Complete Specification Lodged: Accepted: Published: Priori ty: Related Art: This document contains thel ainmendments made under 1 Se, tion 419 and is currect fc riit ing. Name and Address of Applicant: Address for Service: Henkel Kommanditgesellschaft auf Aktien Henkelstrasse 67 4000 Dusseldorf FEDERAL REPUBLIC OF GERMANY Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia I 4 I (i Complete Specification for the invention entitled: A Process for the Production of Ether Carboxylic Acids The following statement is a full d ',cription of this invention, including the best method of performing it known to me/us 5845/3 I 4W.

4. The basic application referred to in paragraph 2 of this Declaration was the first application made in a Convention country in respect of the invention the subject of the application.

Declared at Dsseldorf this 28th day of March 1988 Signatue of eclarant Dr. Geora Zeit .1:

-I-

D 7911 A process for the production of ether carboxylic acids Abstract In processes for the production of ether carboxylic acids corresponding to general formula (I) 9o90 0 0 a o* o* o 90 R- (O-CmHm)_-OCH 2 COH (I) by oxidation of polyalkoxy alcohols correpsonding to general formula (II) R-(O-CMH 2 m)n-OCH 2

CH

2 0H (II) 7W 0 0 04 0 0 0 Oo a 0 06 a 4 a o a in liquid phase with oxygen or oxygen-containing gases in the presence of noble metal catalysts, considerably shorter reaction times are obtained if 0.0001 to I mol of a compound of formula based on the compounds of formula (II) used, is added to the liquid phase before the beginning of the reaction.

1A A Process for the Production of Ether Carboxylic Acids This invention relates to a process for the production of ether carboxylic acids corresponding to general formula (I) R-(0-CmH 2 m)n-OCH 2 COOH (I) in which R is a) a linear or branched CI-C 20 alkyl group, b) an alkylphenyl group substituted by 1 to 3 alkyl groups with the proviso that the sum of carbon atoms in the alkyl substituents is from 1 to 16 or c) a phenyl group, m is 2 and/or 3, and n is from 0 to by oxidation of polyalkoxy alcohols or fatty alcohol alkoxylates corresponding to the formula (II) o, 1 R- (-CmH 2 m)n-OCH 2

CH

2 0H (II) s in which R, m and n are as defined above, oe<o in liquid phase, particularly aqueous alkaline phase, with oxygen or oxygen-containing gases in the presence of effective quantities of nickel, palladium, platinum or a compound of any thereof as catalyst and, o o20 optionally, a catalyst activator, characterized in that 0.0001 to about 1 mol of a compound corresponding to formula based on polyalkoxylates or fatty alcohol alkoxylates of formula is added to the liquid phase before the beginning of the reaction.

Ether carboxylic acids corresponding to formula are important 5 intermediate products for the production of surfactants of the type used, for example, in cosmetic products.

S Examples of the group R in general formulae and (II) are methyl or ethyl groups and also linear or branched alkyl groups, such as propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl groups. Ether carboxylic acids produced particularly frequently are those in which the substituents R are derived from C, 2

-C

18 fatty alcohols of vegetable, animal and/or marine-animal origin or technical mixtures thereof.

._i ethylene oxide and/or propylene oxide. In the case of the ethylene oxide/propylene oxide adducts, the propylene glycol groups may be present in random or block distribution in the alkoxylate chain.

A process of the above-mentioned type for the production of ether carboxylic acids corresponding to general formula using catalyst activators is known from DE-A 31 35 946. Similar processes where a catalyst activator is not used are described in US-B 3,342,858, DE-A 28 16 127 and DE-A 34 46 561. Oxidation with platinum/palladium catalysts is known from EP-A 00 73 545 while oxidation in neutral media is known from DE-A 29 36 123. Other publications describe catalytic oxidation with hydrogen peroxide (EP-A 00 39 111) and with t-butyl peroxide (EP-A 00 18 681).

The present invention is based on the surprising observation that, in the production of ether carboxylic acids corresponding to general formula the reaction times can be considerably shortened both where the I process is carried out continuously and where it is carried out discontinuously providing an effective quantity of ether carboxylic acids 2 \O0 corresponding to general formula is added to the reaction mixture before the beginning of the reaction.

Accordingly, the process according to the invention is characterized in the 0.0001 to 1 mol of a compound corresponding to formula per mol 0o0o t polyalkoxylate or fatty alcohol alkoxylate corresponding to formula II is o added to the liquid phase before the beginning of the reaction. The 000D 0 0 0 o os (T i 1: D 7911 3 I molar ratio of product to educt at the beginning of the reaction may be determined by optimization so that the process, for example where it is carried out continuously, is made economical by reduction of the average residence time in the plant as whole to a minimum. So far as the economy of the process is concerned, an addition of the order of 0.1 to 0.4 mol ether carboxylic acid per mol polyalkoxylate or fatty alcohol alkoxylate is preferred.

A compound corresponding to formula which is identical with the reaction product expected from the reaction is preferably added to the reaction mixture before the beginning of the reaction. However, it is also possible to add other ether carboxylic acids corresponding to formula for example where they are less expensive or easier to obtain than the ether carboxylic acids to be produced by the process according to the invention.

The process according to the invention affords the additional advantage that, for example in the oxidation of linear saturated C12-C14 fatty alcohol polyglycol ethers containing on average 4 ethylene oxide units, the oxidation is carried out above the cloud point of the ethoxylate and the substrate can be emulsified by the ether carboxylic acid added, the process being carried out under the conditions of a micellar catalysis.

The process according to the invention is preferably carried out in aqueous alkaline media, although it may also be carried out in the presence of inert organic solvents.

The reaction temperature is in the range from OC to the 1 boiling point of the reaction mixture and preferably in the range from 40 to 1000C.

The operating pressure required for the process according to the invention is dependent on the partial pressure of the oxygen in the gas used. The pressure range may be from to 40 bar.

The pH value is established by addition of alkalis, pre- L i ii r D 7911 4 S ferably the hydroxides and/or carbonates of sodium and/or potassium. In general, approximately 1 to 1.5 mol alkali is used per mol polyalkoxy alcohol. The alkalis may be added all at once at the beginning of the reaction or, alternatively, may be added during the reaction.

Suitable catalysts are, in particular, platinum and/or palladium in metallic form or in the form of catalytically active compounds thereof. The catalysts may also be applied to solid supports, such as active carbon, silicates, aluminium oxide and the like. The noble metal content of the i supported catalysts may vary within wide limits and is norm- 4 ally from 0.1 to 20% by weight, based on the support material.

The activity and selectivity of the catalysts may be increased by addition of activators, for example lead, bismuth and, optionally, also cadmium in the case of platinum catalysts or bismuth in the case of palladium catalysts, cf. DE-A 31 35 946.

The process according to the invention may be carried out in any apparatus suitable for the performance of liquidphase reactiois with or without application of excess pressure, for example in a stirred vessel or in a bubble column with suspended catalyst or even in a trickling bed reactor charged with catalyst pellets.

The reaction product obtained by the process according to the invention is obtained in the form of an aqueous solution of its alkali salts which may be used as such, for example as a surfactant. However, the free ether carboxylic acids may also be released and isolated in known manner by acidification and, optionally, extraction.

The process according to the invention is described in more detail in the following Examples.

Example 1 500 g distilled water, 1?,97 g active carbon containing by weight palladium, 0.245 g Bi(N0 3 3 as activator, 20.76 g caustic soda and 157.4 g of a linear saturated C12-C14 fatty alcohol polyglycol ether (70 to 75% C 12 24 to 30% C 14 containing on average 4 ethylene oxide units were introduced into a temperature-controlled (heating jacket) 3-liter autoclave of Hastelloy B ("Hastelloy" is a registered trademark of Haynes International Inc.) equipped with a rotary stirrer, internal thermometer and gas inlet. In addition, 18.26 g ether carboxylic acid of the above-mentioned fatty alcohol polyglycol ether (0.1 mol, based on the fatty alcohol polyglycol ether) were added.

After the stirrer had been switched on, the reaction mixture was heated to 90°C. At this temperature, synthesis air (21% by volume 02) was passed through the reactor at 20 bar at a rate of 30 Nl* air per hour.

The course of the reaction was followed at the reactor exit using an oxygen analyzer (*Deutsche Industrie Norm 1343: liter under standard conditions of a temperature of 273.15 K and a pressure of 1.01 bar).

j 15 After the catalyst and the bismuth compound had been filtered off, the filtrate was acidified with dilute sulfuric acid and extracted by repeated shaking with ether to determine the yield. The ether was distilled off from the combined ether extracts after drying over sodium sulfate. The residue was weighed and its acid value determined.

By comparing the experimentally determined acid value of the product obtained with the theoretical value expected of 132.9, it was possible to determine a conversion of 100%.

Comparison Example 1 The procedure was as in Example 1, except that the ether carboxylic acid from the fatty alcohol polyglycol ether used was not added. A complete conversion (100%) was only obtained after a reaction time of hours. Accordingly, the reaction time was 30% longer without the addition of ether carboxylic acid than the reaction time in Example 1.

Example 2 500 g distilled water, 20 g active carbon containing 5% by weight platinum, 7.96 g caustic soda and 100 g of a linear saturated C12-C18 fatty alcohol polyglycol ether containing on average 10 ethylene oxide units were introduced into the autoclave described in Example 1. 18.26 g ether carboxylic acid from the above-mentioned fatty alcohol polyglycol ether were also added (0.1 mol, based on the fatty alcohol polyglycol ether used).

6 At a reaction temperature of 90 0 C, synthesis air (containing 21% by volume 02) was passed through the reactor under a reaction pressure of bar at a rate of 30 N1* air per hour. The experiment was terminated after 6.25 hours when no further consumption of oxygen could be detected. The conversion was determined as described in Example 1, amounting to 100% (theoretical acid value 84.9)(*Deutsche Industrie Norm 1343: liter under standard conditions of a temperature of 273,15 K and a pressure of 1.01 bar).

Comparison Example II The procedure was as in Example 2, except that no ether carboxylic acid was added. The experiment was terminated after 6.25 hours. A conversaton of 81.3% was determined.

4 A I AD1M25 lZ Y 1Z- 0 iI_

Claims (4)

1. A process for the production of ether carboxylic acids corresponding to general formula (I) R-(0-C H 2 m)n-OCH 2 COOH (I) in which R is a) a linear or branched C 1 -C 20 alkyl group, b) an alkylphenyl group substituted by 1 to 3 alkyl groups with the proviso that the sum of carbon atoms in the alkyl substituents is from 1 to 16 or c) a phenyl group, m is 2 and/or 3, and n is from 0 to by oxidation of polyalkoxy alcohols or fatty alcohol alkoxylates corresponding to the formula (II) R-(O-CmH 2 m)n-OCH 2 CH 2 0H (II) in which R, m and n are as defined above, Sin liquid phase, particularly aqueous alkaline phase, with oxygen or o oxygen-containing gases in the presence of effective quantities of nickel, palladium, platinum or a compound of any thereof as catalyst and, optionally, a catalyst activator, characterized in that 0.0001 to about 1 mol of a compound corresponding to formula based on polyalkoxylates or fatty alcohol alkoxylates of formula is added to the liquid phase before the beginning of the reaction.

2. A process as claimed in claim 1, characterized in that 0.01 to 0.4 mol of the compound of formula based on polyalkoxylates or fatty oo alcohol alkoxylates of formula is added.

3. A process as claimed in claim 1 or claim 2, characterized in that the compound of formula to be added before the beginning of the reaction is identical with the reaction product.

4. A process for the production of ether carboxylic acids, substantially as hereinbefore described with reference to any one of the Examples, excluding the Comparative Examples. The product of the process of any one of claims 1 to 4. DATED this TWENTIETH day of SEPTEMBER 1990 Henkel Kommanditgesellschaft auf Aktien Patent Attorneys for the Applicant SPRUSON FERGUSON 5IA1 51Z