DE2432473A1 - PROCESS FOR THE PRODUCTION OF LOW FATTY ACIDS AND HALOGEN FATTY ACIDS - Google Patents

Description

KNAPSACK AKTIENGESELLSCHAFT 2 H W 4 Hf W

Process for the production of acid salts of lower fatty acids and halogen fatty acids

Adducts of lower fatty acids with their alkali salts are described in DT-PS 424 017 and 932 607. In the former This is a process for the preparation of the compounds 3 HCOONa 'HCOOH and HCOONa * HCOOH. For example, trisodium hydrogen formate (3 HCOONa 'HCOOH) is made from 20 to 50 percent Formic acid and sodium formate when heating the reaction mixture to temperatures above 66 C. Isolation the acid salt of the specified composition is carried out after cooling to room temperature by centrifugation, wherein the deposited crystals are separated from the mother liquor. Made from trisodium hydrogen formate Further treatment with more concentrated formic acid forms the acidic sodium formate HCOONa 'HCOOH.

A product that is about the. Composition CH ₃ - COONa '2 CH _x -COOH is obtained according to DT-PS 932 607 when adding glacial acetic acid and anhydrous soda or caustic soda at 100 ° C. and above. This according to the equations

6 CH ₃ -COOH + Na ₂ CO _3: > 2 [CH ₃ -COONa '2 CH ₃ -COOHj

+ CO ₂ + H ₂ O

3 CH ₃ COOH + NaOH ^ CH ₃ COONa '2 CH ₃ -COOH + H ₂ O

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The resulting water of reaction remains at least partially in the end product because it will be used when it is further used as a vinegar substitute or acetic acid in solid form does not interfere.

Also known are a number of analogous adducts of chlorinated acetic acids with their salts; an example is the potassium hydrogen monochloroacetate ClCHp-COOK * ClCH ₂ -COOH (R. HOFFMANN, Lieb.Ann.Chem. W2, 1 to 20 [1857} ). When preparing such compounds, the reaction conditions must be chosen so that subsequent reactions of the chloroacetic acid salts largely do not occur.

It is known that neutral halogen-substituted fatty acid salts are subject to local overheating in their production - especially in the presence of water - easy to pyrolysis, for example Sodium chloride and polyglycolides according to the equation:

ClCH ₂ -COONa> NaCl + ^ (CH ₂ COO) _n ,

and in the presence of sufficient amounts of water with increasing reaction temperature, the hydrolysis increases, e.g. to sodium chloride and glycolic acid according to the equation:

ClCH ₂ -COONa + H ₂ O> NaCl + HOCH ₂ -COOH.

Attempts are made to counteract these decomposition reactions by adding less water to the starting materials or immediately removing the added water and the water formed during neutralization, keeping the reaction temperature as low as possible and the residence time short or maintaining certain pH ranges during neutralization in an aqueous medium,

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e.g. according to DT-PS 860 354, 871 890, 1,113,450, 1,166 and 2,225,867, FR-PS 1,215,896, US-PS 2,446,233 and 2 613 220 as well as GB-PS 706 440 and 782 479-

If the production and isolation of halogenated fatty acid salts is quite complex, one appears technical production of adducts of such salts with the free acids is completely uneconomical. Nevertheless Such substances, e.g. monochloroacetic acid adducts, could be advantageous instead of the corresponding acids or salts are used wherever they are used or processed in an alkaline medium takes place, provided a simple and inexpensive manufacturing process would be available. The firm ones This is because crystalline compounds are - although they disintegrate into their constituent parts in an aqueous medium, and accordingly act as acids - hardly aggressive when dry and can therefore be used like the neutral ones Handle, store, pack and transport salts well. Monochloroacetic acid adducts, for example, can be used instead the aggressive monochloroacetic acid as a starting material for the production of carboxymethyl cellulose as a builder for detergents, thioglycolic acid for cold permanent waves, herbicides and pharmaceuticals. Acid Salts of lower fatty acids can be obtained in solid form by simply dissolving them in water for the preparation of buffer mixtures to serve.

Amazingly, however, contrary to expectations, it succeeded Production of the compounds already mentioned at the beginning and other compounds, some of which were previously unknown, in the simplest possible way Way, when doing this in a fluidized bed - consisting of the substance to be formed - worked will.

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In detail, the invention now relates to a process for the preparation of acidic alkali, ammonium or alkaline earth salts of fatty acids or halogen fatty acids with 1 to 4 carbon atoms by reacting these fatty acids or halogen fatty acids with neutral alkali, ammonium or alkaline earth salts of fatty acids or halogen fatty acids with 1 to 4 Carbon atoms or with the basic components forming these neutral salts, which is characterized in that the starting materials mentioned are introduced into a fluidized bed formed from the resulting acidic salt and an inert gas stream or an inert liquid as fluidizing agent ^{at temperatures of 20 to 200 0 C, and the resulting fluidized bed} , free-flowing acidic salt can be discharged continuously or discontinuously from the fluidized bed reactor depending on its formation.

The method of the invention can also optionally be characterized be that

a) the fatty acid or halogen fatty acid is introduced into the fluidized bed reactor in liquid or dissolved form;

b) liquid fatty acid or molten halogen fatty acid in vapor form into the fluidized bed reactor with the aid of an inert gas stream is introduced;

c) the neutral salt or the basic component forming it in substance, in dissolved or in suspended form in the Fluidized bed reactor is introduced;

d) at the beginning of the implementation the fluidized bed by fluidization solid neutral salt or a solid, neutral salt-forming

.the basic component is formed with an inert gas stream or in an inert liquid; · - - ^! . a-

e) as a basic component, an oxide, hydroxide, carbonate, or - '■] Ammonia is used; · ■■ · "· '""' · ■ .. · - ··.: -

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f) air, nitrogen or carbon dioxide is used as the inert gas stream;

g) the inert liquid used is chlorinated aliphatic hydrocarbons begins;

h) the reaction takes place at temperatures from 50 to 150 ° C;

i) in the case of continuous operation, the starting materials accordingly the discharge of the easily flowable salt obtained from the fluidized bed reactor.

Finally, the invention includes the new substances

1) Acid sodium monochloroacetate of the formula 2 ClCH ₂ -COONa '3 ClCH ₂ -COOH;

2) Adduct of sodium monochloroacetate and acetic acid of the formula

CH ₀ ClCOONa • CH-XOOH.
2 5

Among halogen fatty acids are mainly the chlorine and bromine fatty acids, among alkali salts the sodium and potassium salts, under alkaline earth salts to understand the magnesium and calcium salts.

For the composition and quality of the products received ■ it is irrelevant whether the conversion of the starting materials is carried out batchwise or continuously. About material losses To avoid volatile reaction components, it is possible to circulate the fluidizing agent, whereby any interfering components contained therein, e.g. B. water must be removed.

According to the method according to the invention, the fluidized material is acidic

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Salts of lower fatty acids and halogen fatty acids are suitable, their Granulation allowed the formation of a fluidized bed. However, a system based on this procedure can also be used with a neutral one Salt of the corresponding acid or a suitable solid base component, for example an alkali carbonate, in operation set or operated intermittently, with the corresponding neutral at the equivalence point in the latter case Salt occurs as an intermediate. In addition, fatty acid salts and their halogen derivatives with other than the Acids corresponding to the anion of the respective salt, e.g. sodium formate with acetic acid, can be combined.

Both in batchwise and in continuous operation, the fluidized bed can become one in a manner known per se Fluidized bed can be modified. As a fluidizing agent in this case, besides the stream, there is one for starting and reaction products inert gas as well as an inert liquid, preferably ?: a chlorinated aliphatic hydrocarbon, e.g. CHCl ^, CCl /, trichlorethylene, suitable or can be such an embodiment of the method according to the invention may be advantageous in individual cases.

A particular advantage of the process according to the invention is its economic viability, despite the comparatively long residence times to highlight. The vortex technology allows working in uncomplicated apparatus with little maintenance and Repair effort of almost any order of magnitude. The reactors can be designed in several stages or as a group of Apparatus operated v / earth, which makes the process more efficient because, for example, several reactors one Group can be placed one behind the other in the gas flow. The operation of such a system only requires a comparatively low personnel expenditure.

Products with a fairly high water content and high fines in the grain spectrum tend to stick together. Clumped together

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However, salt components can only be further processed with difficulty, E.g. they do not dissolve easily in water, although they soak up with water. This results in acidic Halogen fatty acid salts as a result of the long dissolution times of such lumps to a partial hydrolysis, even before the Solution has occurred. The consequence of this is a loss in the yield of the secondary products.

The water content of the readily flowable acidic Salts should preferably be below 0.5 weight ^, the content of alkali, alkaline earth or ammonium chloride preferably below 0.5% by weight, if possible below 0.2% by weight, lie.

According to the method of the invention, for example, the following, already known adducts in pure form or in the form of Adduct mixtures are produced:

HCOONa

HCOONa

HCOOK

HCOONH ^ HCOONa

HCOONa

CH ₃ COONa · CH ₃ COONa 'CH ₃ COOK * CH ₃ COOK · CH ₃ COONH ₄ CH ₂ ClCOOK CH ₂ Cl-COONH ₄ CCl ₃ COONa

HCOOH • HCOOH HCOOH • HCOOH

■ CH ₃ COOH

■ 2 CH ₃ COOH

CH ₃ COOH

(see example 2)

CH ₃ COOH

CH ₃ COOH 2 CH ₃ COOH

• CH ₃ COOH

• CH ₂ ClCOOH

¹ CH ₂ ClCOOH 2 CCl ₃ COOH

(see example 5)

CCl ₃ COOK · CCl ₃ COONH ₄ CCIUCOONa · CF ₃ COOK · CBr ₃ COOK

CCl ₃ COOH • CCl ₃ COOH • 2 CH ₃ COOH CF ₃ COOH ■ CBr ₃ COOH

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.CH ^ COONH,. C ^ Hr ₇ COOH

C ₂ H ₅ COOK * C ₂ H ₅ COOH

C ₅ H ₇ COONH ₄ • C ₃ H ₇ COOH

C ₃ H ₇ COOK • C ₃ H ₇ COOH

In addition, the following, previously unknown adducts, among others, can be produced in pure form or in the form of adduct mixtures will:

CH ₂ ClCOONa · CH ₃ COOH (see Example 3) CH ₂ ClCOONa · 2 CH ₃ COOH
2 CH ₂ ClCOONa 3 CH ₂ ClCOOH (see examples 1 and 4)

The existence of addition compounds of monochloroacetic acid with its sodium salt is demonstrated by the phase diagram of the system CHgCl-COONa / CHgCl-COOH / ^ O at 20 ⁰ C, which was already published by J.Pokorny (Z.Chem.1_3, 439 (1973)) describes, however, without being able to specify the composition of the corresponding solid products (soil bodies). The compound 2 'CH ₂ Cl-COONa * 3 CH ₂ Cl-COOH could now be found in the soil body according to a method developed by H. Lux (Inorganic-chemical Experimentierkunst, Verlag Joh.A. Barth, Leipzig, 3rd edition 1970, page 233 ) easily prove the specified procedure.

Example 1 (see Figure 1)

Production of the acidic sodium monochloroacetate 2ClCH ₂ -COONa · 3 ClCH ₂ -COOH

a) discontinuous operation

The experimental apparatus according to Figure 1 of the drawing consists of a jacketed, heatable tube (1) made of glass with an internal diameter of 50 mm and a length of about 1 m with a

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melted frits (2) as an inflow tray. Above that there is a cylindrical extension (3) with a conical shape Transition to the separation and return of the fines into the pipe (1) as the actual fluidized bed reactor. Above Line (4), dust separator (5) and lock (6), the fine particles are discharged. The exhaust gas escapes Line (7).

Acid for batchwise production Natriummonochloracetates be presented (1) 400 g of anhydrous soda in the tube and vortexed as an inert fluidizing gas via conduit (8) at 80 to 100 ⁰ C with about 1 h rrr / nitrogen. From the receiver (9), which is kept at 80 to 90 ^° C., with 1800 g of molten monochloroacetic acid, its vapors are blown into the tube (1) at 1 to 2 m / h nitrogen via the line (10), which is also temperature-controlled. The molten monochloroacetic acid was introduced into the receiver (9) via line (11). After about 8 hours, the fluidized material no longer consists of soda but, as a result of the gradual conversion, essentially consists of monochloroacetic acid sodium ("neutral salt", ClCHp-COONa); After a further 8 hours or so, the reaction is complete and the acidic sodium monochloroacetate is removed under the pressure of the nitrogen gas through the nozzle (12) attached above the frit (2) (1360 g). For temperature and pressure measurement, nozzles (13) are distributed over the entire length of the reactor (1).

b) continuous operation (see Figure 2)

For the continuous implementation of the conversion of monochloroacetic acid with calcined soda to acidic sodium monochloroacetate is a group of two of those described under a) Reactors are suitable, with a screw conveyor in each case in the upper part of the heatable tube (1) (16) opens, via the 50 g / h soda or that formed from it in the 1st reactor and continuously via the nozzle

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(12) discharged "neutral" sodium monochloroacetate (108 g / h) are metered in (cf. FIG. 2). The one of the screw conveyor (16) upstream storage bunker (15) is fed via line (14). The discharged from the two dust separators (5) Fine fractions are also returned to the 1st reactor via line (14). At the same time, the discharge nozzle (12) of the 2nd reactor, the acidic sodium monochloroacetate formed (242 g / h) is continuously withdrawn. The swirl material is used in the 1. Reactor 600 to 800 g of monochloroacetic acid sodium, its production e.g. from calcined soda and monochloroacetic acid can have taken place in advance, and in the 2nd reactor 600 to 800 g - for example, acidic sodium monochloroacetate prepared analogously.

The reference numbers 1 to 13 in FIG. 2 have the same meaning as in FIG. 1.

In order to avoid losses of monochloroacetic acid in the 2nd reactor, the fluidizing gas can be guided in countercurrent by the exhaust gas of the 2nd reactor is fed to the 1st reactor via a temperature-controlled line. In this case, a total of 225 g / h of monochloroacetic acid are used consumed, which must be added to the two templates (9).

The products obtained according to a) and b) are fairly coarse-grained and readily flowable. The bulk weight is about 0.9 kg / Liters and the grain spectrum is roughly as follows:

> 0.4 mm 6 _t 7%; 0.4 to 0.2 mm 15.6%; 0.2 to 0.063 mm 70.1 %; <0.063 mm 7.6 %.

The product mixture obtained according to a) and b) consists essentially of the compound 2 CK ₂ ClCOONa * 3 CH ₂ ClCOOH.

The composition of the product according to a) is as follows (Weight%):

sodium monochloroacetate 44.8

Monochloroacetic acid 55.0 (calc. 54.89)

Sodium chloride 0.1

Water 0.1

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Example 2

Production of the acidic sodium acetate CH ^ -COONa · CH ₃ -COOH (discontinuous procedure)

In the experimental apparatus described in Example 1 a) 400 g calcined soda are introduced and heated to 50 to 8O ⁰ C. From the ^{receiver (9), which is kept at 50 °} C. and containing 1200 g of anhydrous acetic acid, its vapors are blown into the tube (1) at about 0.5 m / h nitrogen. After 8 hours, the fluidized material consists essentially of anhydrous sodium acetate; after a further 8 hours, the reaction has progressed to the acidic sodium acetate stage. The reaction product is quite coarse-grained and can be removed under the pressure of the fluidizing agent (nitrogen) via the discharge nozzle (12) (960 g) Fluidizing agent is passed with the unreacted vinegar vapor in the circuit or via a downstream heated reactor filled with fresh soda. The acidic sodium acetate (pH = 4.5) obtained by this process had the following composition (Ge weight s 90):

Sodium acetate 56.3 (calc. 57.7) acetic acid 43 ^ 7 (calc. 42.3)

and was completely anhydrous. The product flowed well and had a bulk density of 0.6 kg / liter.

Example 3 (see Figure 3)

Production of an adduct from sodium monochloroacetate and acetic acid (continuous working method)

For the production of a solid adduct from sodium mono-

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chloroacetate and acetic acid, a two-stage reactor according to Figure 3 of the drawing is suitable. In the reactor (1) there is a gas-permeable intermediate floor (21) with an overflow pipe (22) through which the solids fed in via the screw conveyor (16) reach the lower stage of the reactor. 200 g / h of acetic acid are injected into the reactor (1) via line (17) using 800 l / h of air flowing through line (18), while at the same time a further 700 to 1000 l / h via line (20) and inflow tray (2) Air can be introduced. The air is preheated in the heat exchanger (19) in order to ^: Avoid the crystallization of acetic acid in the nozzle. The temperature in the reactor (1) is kept at about 50.degree.

About 1000 g of solid adduct had been placed in the reactor (1) as a fluidizing agent, the production of which is possible in the same apparatus with sodium monochloroacetate as the fluidizing agent. At the beginning of the acetic acid supply, 350 g / h of sodium monochloroacetate are metered in via the screw conveyor (16) and at the same time about 530 g / h of the adduct formed are withdrawn via the discharge nozzle (12). The fine particles discharged from the dust separator (5) are returned to the reactor (1). The adduct is free-flowing and contains 35.8% by weight (calculated 34.0% by weight) of free acetic acid.

The reference numbers 1 to 7, 12 and 13 on the one hand and 14 to 16 on the other hand have the same meaning as in the figures

1 and 2 of the drawing.

Example 4 (see Figure 4)

Production of the acidic sodium monochloroacetate

2 CH ₂ Cl-COONa · 3 CH ₂ Cl-COOH ■ ■ ■

in suspension (discontinuous operation)

In a heatable fluidized bed reactor (31) according to FIG. 4 of about 2 1 capacity with side circulation pipe (32)

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159 g of anhydrous soda are suspended in 1800 ml of carbon tetrachloride. At 75 to .80 ⁰ C in this suspension 300 g molten monochloroacetic acid dissolved in 300 ml of warm carbon tetrachloride are added dropwise over the connecting piece (33) in the course of 2 to 3 hours, and at the same time about 200 ml / h of carbon tetrachloride over the line are ( 34) distilled off, the majority of the water formed in the reaction passing over and, after condensation of the vapors in the cooler (35), can be separated from the specifically heavier carbon tetrachloride via line (36). By metered reflux of carbon tetrachloride via line (37), the liquid level in the reactor (31) is kept above the upper attachment of the circulation line (32). Steam (water and CCl-) and reaction exhaust gas (CO, -) maintain the circulation and thus the fluidized bed in the liquid phase; the exhaust gas escapes via line (38).

Then, in the course of a further 5 hours, another 425 g of monochloroacetic acid mixed with 500 ml of carbon tetrachloride are introduced while hot. The suspension is cooled to 20 ° C. and removed via the outlet connection (39). After the carbon tetrachloride has been separated off and dried, 768 g of acidic sodium mochloroacetate are obtained; the yield is over 99 %, based on the sodium carbonate used. The product has the following analytical values (weight ^):

23.4 % C (calc. 23.25 %)

2.6 % H (calc. 2.53 %) 34.3 % Cl (calc. 34.34 %)

8.9 % Na (calc. 8.90 %) monochloroacetic acid content 54.98 % (calc. 54.89)

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Example 5

Production of the acidic ammonium _{monochloroacetate CH 2} Cl-COONH ₄ * CH ₂ Cl-COOH
(continuous working method)

If the apparatus according to FIG. 4 is provided with a gas inlet pipe at the bottom, it is also suitable for the production of acidic ammonium salts according to the invention. In order to produce acidic ammonium monochloroacetate, 250 g of this compound are suspended in 1.8 liters of carbon tetrachloride and placed in the reactor 31. In this suspension is continuously passed in at 20 to 5O ⁰ C for 30 to 40 l / h NH ₇ and simultaneously dropped over the connecting piece (33) every hour 150 g molten monochloroacetic acid dissolved in 1 liter of warm carbon tetrachloride to, while a corresponding amount of salt suspension is removed from the apparatus via the outlet nozzle (39). The yield of acidic ammonium monochloroacetate is almost quantitative after filtering and drying, provided that the excess components NH ^ and monochloroacetic acid dissolved in the filtrate (CCl /) are recycled. The free-flowing product contains about 0.1% by weight of ammonium chloride.

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Claims (12)

Patent claims: 1) Process for the production of acidic alkali, ammonium or alkaline earth salts of fatty acids or halogen fatty acids with 1 to k carbon atoms by reacting these fatty acids or halogen fatty acids with neutral alkali, ammonium or alkaline earth salts of fatty acids or halogen fatty acids with 1 to 4 carbon atoms or with these Basic components forming neutral salts, characterized in that the starting materials mentioned are introduced into a fluidized bed formed from the resulting acidic salt and an inert gas stream or an inert liquid as a fluidizing agent at temperatures of 20 to 200 C, and the resulting, readily flowable acidic salt accordingly its regeneration can be discharged continuously or discontinuously from the fluidized bed reactor. 2) Method according to claim 1, characterized in that that the fatty acid or halogen fatty acid is introduced into the fluidized bed reactor in liquid or dissolved form will, 3) Method according to claim 1, dadu rch g e indicates that liquid fatty acid or molten halogen fatty acid is introduced in vapor form into the fluidized bed reactor with the aid of an inert gas stream. 4) Method according to one of the preceding claims, since by ge ke nnz ei chnet that the neutral salt or the basic component forming it is introduced into the fluidized bed reactor in substance, in dissolved or in suspended form. - 16 5 0 9 88 A / 1 1 0 7 BATH ORIGINAL 5) Method according to claim 1, characterized in that at the beginning of the reaction the fluidized bed is formed by fluidizing solid neutral salt or a solid, neutral salt-forming basic component with an inert gas stream or in an inert liquid. 6) Method according to one of the preceding claims, characterized in that an oxide, hydroxide, carbonate or ammonia is used as the basic component. 7) The method according to any one of the preceding claims, d a by gekennze iehnet that air, nitrogen or carbon dioxide is used as the inert gas stream. 8) Method according to one of claims 1, 2, 4, 5 or 6, characterized in that chlorinated aliphatic hydrocarbons are used as the inert liquid. 9) A method according to any one of the preceding claims, characterized in that the reaction takes place at temperatures of 50 to 150 ⁰ C. 10) Method according to one of the preceding claims, characterized in that during continuous operation the starting materials according to the discharge of the recovered well fluid salt are introduced from the fluidized bed reactor. - 17 - SQ9884 / 1107 11) Acid sodium monochloroacetate of the formula 2 ClCHp-COONa 3 ClCH ₂ -COOH. 12) Adduct of sodium monochloroacetate and acetic acid of the formula CH ₂ ClCOONa 'CH ₇ COOH. 509884/1107