CS254225B1 - A method for producing metal salts of carboxylic acids - Google Patents

Abstract

The subject matter is the production of metal salts of carboxylic acids, especially C2 to C6 acids, from a mixture of sodium salts of C2 to Ce acids, which are obtained as a by-product from the process of catalytic oxidation of cyclohexane to cyclohexanol and cyclohexanone, further from a by-product of oxygen-containing organic products after preliminary neutralization or saponification, and from a neutral or alkaline aqueous solution of a metal salt of an inorganic acid, such as: ferrous sulfate, ferric sulfate, ferric chloride, cobalt nitrate, nickel nitrate, manganese sulfate, etc. Their preparation with stirring at 0 to 100 °C is most often carried out in the presence of an organic solvent, a suitable component of which are polar organic compounds. The method is suitable mainly for the preparation of catalytic solutions, as well as for the production of siccatives, additives to lubricants, fuels, etc.

Description

254225 4

The present invention relates to a process for the production of carboxylic acid metal salts, mainly in the form of a solution in an organic solvent, by using by-products from the cyclohexane oxidation process to cyclohexanol and cyclohexanone.

The metal salts of carboxylic acids such as oleic acid, stearic acid, 2-ethylhexanoic acid, naphthenic acids and tallow acids are widely used as catalyst precursors in natural organochemical processes, as coatings, additive additives, and wood preservatives. , hydrocarbon fuel fuel firing activators.

Metal salts of organic acids, especially carboxylic acids, are prepared by melting fatty acids or other carboxylic acids with oxides, hydroxides, carbonates, inorganic metal salts or metal salts of lower aliphatic acids (V. Brit. Ipat. No. 942 542).

It is also known (Kastens ML, Hansen RF: Ind. Eng. Chem. 41, 2080 (1949)) for the preparation of metal salts of organic acids in which aqueous solutions of alkali metal salts of organic acids are precipitated with an aqueous solution of inorganic acids. salts. The resulting metal salt of the organic acid is washed with water, dried for a few hours at an elevated temperature, vacuum and finally dissolved in a suitable solvent. However, the two processes commonly used are discontinuous, time-consuming, low-yielding.

The above-mentioned drawbacks are remedied in part by the process for the preparation of metal salts of organic acids (Oksosintez, p. 74. Gostoptechnizdat, Leningrad 1963). In the first stage, a solution of the alkaline salt of the organic acid is precipitated with an aqueous solution of the metal inorganic acid in the presence of a solvent at a temperature of 60 to 80 ° C, the salt of which is used in a slight excess or an equivalent amount. In a second step, an additional aqueous solution of an alkaline salt of an organic acid is added to precipitate unreacted metal which remains dissolved in the inorganic salt form in the aqueous layer. The process is complicated, whereby the efficiency of the metal salt organic acid formation in each stage is low. The preparation of the metal salts of carboxylic acids (according to U.S. Pat. No. 126,708) is carried out by reacting the alkaline salt of the organic acid and the metal salt of the norganic acid in a single stage with an excess of organic acid or alkali hydroxide in an amount of 0.1 to 45%, respectively. . 0.1 to 50%. It limits the saliva to metallic salts of higher fatty acids, generally pure. In addition, the salts of said metals formed with higher fatty acids are insoluble in water, but relatively soluble in most non-polar organic solvents.

However, solubility in lower alkanes or cycloalkanes for several applications is not yet sufficient. In addition, the sources of higher fatty acids are limited, and I require them to do so! in addition to the preparation of their sodium salts.

However, the process for producing metal salts of carboxylic acids, mainly in the form of a solution in an organic solvent or in solvents, by reacting alkali salts of carboxylic acids and / or carboxylic acid esters and / or carboxylic acids with an aqueous solution or aqueous solutions of metal salts of inorganic acids, at a temperature of 0 to 150 ° C, generally under intensive stirring, in the form of sodium salts of mainly monocarboxylic acids C2 to C6 in aqueous solution as by-product and / or acidic by-products of organic acids from the process of catalyzing the oxidation of cyclohexane to cyclohexanol and / or cyclohexanone, optionally by neutralization and / or saponification with an alkali metal hydroxide, reacts with a neutral or alkaline aqueous solution of the inorganic acid metal. After the salts have been thickened from 70 to 100%, the aqueous phase is separated from the reaction medium by the alkali metal salt and the inorganic acid. The advantage of the method according to the invention is the technical simplicity, the small apparatus and the time, the possibility of technical-economical evaluation has been achieved only by the low-valued so-called. alkaline effluents from the cyclohexanone production process by the cyclohexanone oxidation process by the cyclohexane oxidation process, practically unmodified, for the production of metal salts of carboxylic acids C2 to Ce, cobalt, nickel, and ferrous salts.

The process also makes it possible to use oxygen-based organic by-products from the process of catalytic oxidation of cyclohexane to cyclohexanol and cyclohexanone for the production of metal salts, and also, as their solvent, to utilize the pre-alcoholic by-products of the process. Last but not least, it also makes it possible to produce cobalt salts or solutions in cyclohexane and in the alcohol fraction as catalyst solutions prior to the process of oxidation of cyclohexane, thereby preventing the introduction of foreign matter into the process.

Suitable alkali salts of the carboxylic acids of the present invention are the sodium salt of mixtures of monocarboxylic acids C2 to C6, which are removed from the process of catalytic oxidation of cyclohexane to cyclohexanol acyclohexanone, the so-called alkaline waste water, most often at pH 8 to 11, solidification temperature of 21 to -50 ° C, dry matter 20 to 45 percent by weight; % 15 to 25 wt% water; 60 to 75 wt% water;

This aqueous solution, generally containing 234223 free alkalinity, mainly consists of a mixture of acetic acid (usually in the range of 2 to 6% by weight); sodium propionate (usually 1 to 5% by weight); sodium butyrate (usually in the range of 7.7 to 11.7% by weight) and sodium n-caproate (most often in the range of 0, 2% by weight); 5 to 3% by weight). It may also contain admixtures of hydroxycaproic acid salts and esters and other unidentified oxygen-organic compounds. However, so-called alkaline waters without undissolved impurities are most suitable for the production of the metal salts of the present invention.

Another carboxylic acid donor of the present invention is a side-oxygenated organic product from the cyclohexane oxidation process to cyclohexanol and cyclohexanone, isolated as a distillation residue (so-called MEK), free of part of the water from the hydrolysis column having the following: acid number 100 up to 350 mg KOH / g, most commonly 250 + 50 mg KQH / g; saponification number 250 to 480 mg KOH / g, most often 400 + 30 mg KOH / g; bromine number 5 to 30 g Br / 100 g and 2 to 8 wt. OH.

Particularly suitable is the forward portion, separated from the front. by differential distillation from this residue under reduced pressure, in particular: a fraction of 20 to 150 ° C / 2.67 kPa (number = 225 + 25 mg KOH / g; saponification number = 320 + 30 mg KOH / g; OH = 6.5) + 2%;

IfcO - 20 + 10% by weight) or even an increased proportion. By treatment with alkali hydroxide, not only are the free acid salts formed, but a) from saponified esters and lactones. For neutralization and saponification it is preferable to use sodium hydroxide, optionally potassium hydroxide.

Suitable metal salts of inorganic acids are, in particular, sulphates, nitrates, chlorides, phosphates and carbonates. Particular sulphates, nitrates, chlorides, phosphates and carbonates of divalent and trivalent cobalt, nickel, divalent manganese, divalent and monovalent media.

The reaction is usually carried out under intensive stirring of the reaction medium. For most applications, it is desirable to prepare metal salts in the form of solutions in an organic solvent. Since they are predominantly metal salts of lower carboxylic acids C 2 to C 6, optionally hydroxy acids G 4 to C 6, their solubility in non-polar solvents is lower, they may not be combined (cyclohexane, n-hexane, n-alkanes C6 to C18 and the polar organic solvents (alcohols, esters, ethers, ketones and the like).

Such a suitable polar organic solvent is the predominant alcoholic by-product of the catalytic oxidation of cyclohexane to cyclohexanol and cyclohexanone isolated by rectification of predominantly cyclohexanol-cyclohexanone mixture (on an FK-102 column). It is a colorless liquid, of which 93 + 5%, with a density of 840-885 kg, from which a temperature range of 92 to 142 Ό / 101 kPa is distilled. m-3; OH = 8 to 23% by weight; saponification number = 10 to 60 mg KOH / g.

It usually contains: 48 to 53% amyl alcohol 3 to 5% isoamyl alcohol 8 to 10% n-butanol; 5 to 7% isobutanol; 1 to 2% of sec-butyl alcohol; 14-20% cyclohexanone; 6 to 10% cyclopentanol; 3 to 6% cyclopentanone and about 2% water. Furthermore, admixtures of cyclohexane, cyclohexene and cyclohexanol constitute about 1%.

Less suitable is also the by-product of cyclohexane oxidation, isolated as a desilting residue from the separation step of the cyclohexanol oxidation mixture of cyclohexanol-cyclohexanone (heavy fraction of FK-105). This heavy fraction, usually dark-colored, wafts at a temperature of 20 ° C in the range of 960 to 980 kg. m-3 and at a temperature range of 150 to 263 ° C / 101 kPa, 93 + 5%; the acid number is in the range of 0.3 to 3 mgKOH / g; bromine number 100 to 280 g Br / 100 g; hydroxyl content of 2 to 10 ° / wt. and carboxyl groups of 3.5 to 14 wt.

Thus, in the case of the determination of the cobalt salt as the cyclohexane oxidation catalyst, a suitable cobalt sol1 is fed to the process in the form of a solution consisting of the foregoing alcoholic by-product (FK-102) and cyclohexane; in the case of application in the production of dimethylterephthalate in a solvent consisting of, in addition to, organic polar components and of p-xylene. In order to prepare the cobalt salt of preoxoprocess, it is desirable to prepare the salt by the presence of the side oxygen product of oxoprocess and toluene, optionally higher alkali and the like.

The production method of the present invention is best performed discontinuously and locally. but maybe you can't make it happen. Further details on the practice of the method of the invention, which are not limited thereto, as well as other advantages are apparent from the examples. Example 1

Into a three-necked flask with a volume of 0.5 dm 3, 65 g of so-called alkaline water coming from the production of cyclohexanone-cyclohexanol by catalytic oxidation of cyclohexane, remaining mainly from an aqueous solution of sodium carboxylic acids C2 to Ce (pH-10); alkalinity = 47.3 mg KOH / g; OH = 2.3%; bromine number = 8.2 g Br / 100 g; water = 71%; ash - 10.7 wt%; after acidification with mineral acid is obtained! organic acids that make up the alkali water: acetic acid 0.9% by weight; propionic acid 0.6% (w / w) butyric acid 3.6% (w / w) valeric acid (10.9%) and caproic acid (1.1% w / w), esters of monocarboxylic acids and dicarboxylic acids (semiesters) with 20 g of a solution of nitrate-cobalt hexahydrate at a concentration of 12.5% by weight of cobalt and 140 g of a fertile alcoholic product as a solvent isolated by rectification of the predominantly cyclohexanol-cyclohexanone mixture on a column (FK-102) are added at 45 ° C cyclohexanone through an intermediate mixture of cyclohexanol-cyclohexanone by catalytic oxidation of cyclohexane.

The density of the colorless liquid in the following is referred to as the product FK-102) at 20 ° C = 855 kg. m “3 and within the range of 92 to 142 ° C / 101 kPa distilling 95%; acid value = 0.95 mg KOH / g; OH = 14.3%; 00 = 1.6% by weight; contains (in% by weight): 51.9% amyl alcohol, 3.7% isoamyl alcohol, 9.5% n-butanol, 5.6% isobutanol, 1.1% sec.butyl alcohol, 19.7% cyclohexanone, 8.0% cyclopentanol, 5, 0% of cyclopentanone and 3.6% of water The admixtures of cyclohexane, cyclohexane and cyclohexanol amount to about 1%.

The mixture thus prepared is stirred at 50 ± 2 ° C for 3 h. After separation of the organic and aqueous phases, 178 g of a solution of the cobalt salts of organic acids C2 to 06 are obtained as an organic phase with a concentration of 1.38% by weight. of co-balt and 46 g of an aqueous sodium nitrate solution containing 0.06 wt. residual cobalt in the form of cobalt salts. From a third of the organic phase - a solution of co-salt salts - the solvent is distilled off under reduced pressure, thereby recovering and obtaining a solid cobalt salt of mainly carboxylic acids C2 to 06. Example 2

Into a three-necked flask with a volume of 0.5 dm 3, equipped with a stirrer, weigh 65 g of so-called residual alkaline waters (mainly sodium solicarboxylic acids C2 to 06 and impurities and esters and semi-esters of dicarboxylic acids) from the cyclohexanone production by catalytic oxidation of cyclohexane to a mixture of cyclohexanol and cyclohexanone as specified in Example 1. 20 g of an aqueous solution of nickel nitrate with a content (calculated on Ni) of 8.97 percent by weight are further added with stirring. and 84.4 g of the anterior alcoholic byproduct FK-102, also specified in Example 1.

Reaction components are stirred at 240 DEG C. for 50 min. Thereafter, the stirring is stopped, 119.6 g of the organic phase, consisting of an organic solution of nickel salts of carboxylic acids C2 to C6 (expressed as Ni), is separated by 1.48% by weight. nickel. An aqueous phase of 47.4 g forms an aqueous solution of sodium nitrate with admixed salts in an amount of 0.05% w / w. P r i k 1 and d 3

Into a three-necked flask of 0.5 dm 3, 65 g of so-called waste alkaline water are prepared by the production of cyclohexanone, specified in Example 1, followed by 20 g of an aqueous solution of ferric chloride (by dissolving FeCH. 6H 2 O) at a concentration of 9.18% by weight. iron and the mixture was heated to 80 + 1 ° C for 60 min. 120 g of the solvent FK-102 specified in Example 1a are then added and the reaction mixture is maintained at a temperature of 50 ± 1 ° C with stirring for 180 min. Upon discontinuation of mixing, the reaction was disaggregated. The upper organic phase in the amount of 145.5 g is a solution of the

Claims (4)

254 9 of those carboxylic acid salts of C2 to C6 with a concentration of 1.48 wt. irons. The 56.6 g aqueous solution is a substantially aqueous sodium chloride solution containing 0.0032 wt. irons. P r i k 1 and d - 4 Into the three-necked volume bank. 0.5 dm3 opa-trene with stirrer, thermometer and spatula. weigh 65 g of the so-called alkaline waste water specified in Example 1, 45 g of a green vitriol solution, respectively. ferrous sulfate prepared by dissolving 125 grams of FeSCht. 7 H2O in 500 g of water and 120 g of solvent FK-102 specified in Example 1. The reaction mixture was stirred for 300 min. at 50 + 1 ° C. After separation of the layers in a separatory funnel, 151.7 g of a solution of a mixture of ferrous salts of C2-C18 acids containing 1.179% by weight are obtained. of iron and 76.6 g of other water containing sodium sulfate and admixing ferrous salts with a concentration of 0.03% by weight. EXAMPLE 5 11 g of a mixture of n-valeric acid with caprone, prepared by adding sulfuric acid to the so-called alkaline effluents from the production of cyclohexanone, are weighed into a three-necked flask with a volume of 0.5 dm <3>, containing a stirrer, thermometer and a back-up. in Example 1 and rectifying the released C2 to Cs acids under reduced pressure. Furthermore, 13 g of an aqueous solution of sodium hydroxide at a concentration of 40% by weight are added. thus adjusting the pH of the solution to 8-9. Thereafter, 20 g of an aqueous solution of nitrocyanobalt containing 10,1% by weight is added with stirring and at 70 ± 2 ° C. of co-balt and 140 g of the organic solvent FK-102 specified in Example 1. The reaction mixture is maintained for 240 min under said conditions. After interruption and cooling to room temperature, the reaction mixture is disaggregated. 156 g of the top organic layer is an organic solution of a mixture of valerane and cobalt caproate containing 1.25% by weight. cobalt and the aqueous (bottom) layer in an amount of .65 g .ltoreq.1050 form a substantially aqueous solution of nitrous sodium admixed with 0.09 wt. Example 6 Preparation of a mixture of cobalt valerate salt with caproate cohaltium is prepared similar to Example 5. Only the solvent solvent FK-102 is applied with 30 g of n-butanol. Upon completion of the reaction, the lower layer is separated, the upper organic layer is washed with water and the wash water is also dissolved in the effluents. Then, the organic solvent is distilled off and a 15% by weight mixture of cobalt (II) cobalt salts of capric acid is obtained. . cobalt. Example. To a three-necked flask with a volume of 0.5 dm 3, an O-containing stirrer, a thermometer and a back-up mixer were weighed 65 g of the so-called alkaline waste water from the cyclohexanone production by the x-oxidation of cyclohexane specified in Example 1, 20 g of an aqueous solution of cobalt nitrate. 12.5 wt.% Cobalt and 30 g of solvent FK-102, also specified in Example 1. The water content is heated for 60 min. on. 100 ° C to 120 ° C and refluxed. After cooling to 50 ° C, 140 g of cyclohexane are added and stirring is continued for 180 min. Upon completion of the reaction and stopping the agitation, an aqueous layer of homogeneous solution of a mixture of co-salts of carboxylic acids C2 to Ce is obtained. The lower layer consists essentially of an aqueous solution of sodium nitrate with admixture of co-bald pigs with a concentration of 0.04% cobalt. EXAMPLE 8 A procedure similar to Example 7 was followed, only 140 g of p-xylene were added instead of 140 g of cyclohexane. The resulting solution of a mixture of co-salts of carboxylic acids C2 to Cs in an organic solvent is suitable for standardizing the catalyst solution to produce methyl terephthalate by catalytic oxidation of xylene. P R E D Μ E T A process for producing metal salts of carboxylic acids, mainly in the form of a solution in a 7-organic solvent or in solvents, by reacting alkali metal salts of carboxylic acids and / or carboxylic acid esters and / or carboxylic acids with aqueous or aqueous inorganic acid salts , at a temperature of 0 ° C to 150 ° C, generally under intensive mixing, characterized in that the mixture of sodium ions and the salts of mainly monocarboxylic acids C 2 -C 8 in aqueous solution as a by-product and / or secondary oxygenated organic products from the process of catalytic oxidation of cyclohexane to cyclohexanol and / or cyclohexanone, optionally after neutralization and / or saponification with an alkali metal hydroxide, reacts with a neutral or alkaline aqueous solution of inorganic metal salt 11 12 234225 of the acid, wherein after cation exchange, the solubility is 70-100% and aqueous an alkali metal and inorganic acid reaction phase environment. 2. Process according to claim 1, characterized in that the reaction is carried out in the presence of an organic solvent, preferably containing a polar component of hydrogen sulfide and / or a mixture of organic solvents, preferably a mixture of cyclohexane and ether-xylene and a predominant alcoholic solvent. of the product from the catalytic cyclohexane oxidation, the isolated recrystallization mainly of the cyclohexanol-cyclohexanone mixture containing mainly amyl alcohol, n-butanol, isobutanol, acyclohexanone sec-butyl alcohol. 3. Process according to clauses 1 and 2, characterized in that after completion of the synthesis of the metal solicaric acids and separation of the aqueous phase, at least a portion of the solvent is separated or its concentration is adjusted by the addition of an additional amount of organic solvent. 4. Process according to claim 1, characterized in that when the metal salts are synthesized and, as a rule, separated from the aqueous phase, they are brought into solution in an organic solvent.