RU2258692C1 - Method for treatment of complex organic mixtures from carbonyl compounds and acids - Google Patents

Abstract

FIELD: chemical technology.

SUBSTANCE: invention relates to the improved method for treatment of organic mixtures from carbonyl compounds and acids by their treatment with sodium sulfite. Method involves using organic mixtures comprising carbonyl compounds and carboxylic acids in the ratio = 1 g-equiv. : 1 g-equiv. or with excess of acids, or with excess of carbonyl compounds. In this case before treatment with sodium sulfite carboxylic acid is added to the parent mixture in the amount to obtain the ratio of carbonyl compounds to acids as 1 g-equiv. per 1 g-equiv. and treatment is carried out with solid sodium sulfite in beaded mill with the mass ratio of the composition charge to glass beads as a grinding agent = 1:(1-2) at the rate of mechanical mixer rotation 1440 rev/min, not less, and in dosing sodium sulfite 1.2-1.5 mole per 1 g-equiv. of carbonyl compounds or excess of acid in the presence of stimulating additive up to practically complete consumption of carbonyl compounds, or carbonyl compounds and acids. Process is carried out in the presence of sodium and potassium hydroxide and acetate and sodium nitrate also as a stimulating additive taken in the amount 1-4% of mass sodium sulfite to be added up to practically complete consumption of carbonyl compounds and acids in composition to be treated. This simple method provides high degree of purification being even in small parent content of carbonyl compounds and acids.

EFFECT: improved method for treatment.

4 cl, 3 tbl, 19 ex

Description

The invention relates to one of the types of purification of complex organic mixtures from the aldehydes, ketones and carboxylic acids contained in them and can be used in various industries to improve the quality of such compositions for their intended purpose, the utilization of carbonyl compounds, in waste and environmental pollution recycling schemes, and in many other cases.

It is known to use sodium sulfite to interact with an aldehyde in order to protect the aldehyde group for further chemical transformations (a.c.SSSR No. 571472).

Its disadvantage is that the treatment is carried out with an aqueous solution of sodium sulfite, and the desired pH of the aqueous phase (7.0-8.3) is supported by the introduction of appropriate acid additives.

Closest to the claimed one is a method of separating an aldehyde from essential oils containing it (a.c.SSSR No. 1774616) by treating the latter with an aqueous solution of sodium sulfite and neutralizing the alkali formed during this process with carbon dioxide so that during the process the pH remains in the range of 9, 0-9.5 with a decrease to 8.0 at the end of the process.

The disadvantage of this method, as described above, is that the processing of the organic composition is carried out with an aqueous solution of sodium sulfite. From the point of view of aldehyde evolution, this is probably not bad, but from the point of view of further use of the remaining organic composition, such treatment entails additional washing with water to remove residues containing sodium sulfite and a hydrosulfite derivative of the aqueous phase, and then drying, which is not always rational and profitable for technological and economic reasons, and sometimes simply unacceptable.

In addition to the main drawback, you can specify a number of others:

1. The extraction of aldehyde does not automatically predetermine that ketones can be extracted in a similar way, since the reactivity of the latter is several orders of magnitude lower than that of aldehydes.

2. The recovery of the aldehyde present in large quantities in the system cannot be identified with the purification of the composition of relatively small amounts of carbonyl compounds. In the first case, 80% recovery of the target component is a good result, and a degree of purification of 80% is a very rough cleaning.

3. The duration of the extraction process is quite large (for example 1 ~ 3 hours). It can be expected that when working with low concentrations of carbonyl compounds (1-4% instead of 40-70%), it can additionally increase significantly.

4. Carbon dioxide to maintain pH as a result of neutralizing the alkali formed in the chemical interaction is not a very good reagent (it is poorly soluble in water, carbonic acid is rather weak). In organic media, CO _{2 is} soluble in many cases even worse, and no carbonic acid can form. In other words, one will have to deal with the heterogeneous heterophasic interaction of dissolved CO ₂ with solid sodium sulfite, which is far from the same thing.

The objective of the proposed solution is to replace the treatment of the organic composition with an aqueous solution of sodium sulfite in order to extract carbonyl compounds from it and purify them and, in parallel, from acids, to treat it with dry solid sodium sulfite and to extend this technique not only to mixtures of aldehydes and carboxylic acids, but also to various ketones and mixtures of aldehydes and ketones individually and together with carboxylic acids.

The problem is solved in that organic mixtures containing carbonyl compounds and carboxylic acids in a ratio of 1 g-equiv: 1 g-equiv or with an excess of acids or with an excess of carbonyl compounds are taken for processing, in this case, before treatment with sodium sulfite an amount of carboxylic acid is added to the initial mixture in such an amount as to bring the ratio of carbonyl compounds and acids to 1 g-equiv per 1 g-equivalent, and the treatment is carried out with solid sodium sulfite in a bead mill with a mass ratio of the loading of the composition and glass beads 1: 1-2 and a rotation speed of the mechanical stirrer of at least 1440 rpm at a dosage of sodium sulfite 1.2-1.5 mol per 1 g-equiv of carbonyl compound or in excess of acid in the presence of a stimulating additive to practically complete consumption of carbonyl compounds or carbonyl compounds and acids.

At the same time, an acid having the lowest possible molecular weight and not interfering in trace amounts with the use of the purified composition for its intended purpose is used as the added carboxylic acid.

As a stimulating additive, hydroxides and acetates of sodium and potassium and potassium nitrate are taken in an amount of 1-4% by weight of the introduced sodium sulfite, respectively. In the case of the initial compositions with a relative viscosity of more than 37 s using a VZ-4 viscometer (20 ° C), they are diluted with an appropriate solvent.

Characteristics of the raw materials used

Sodium sulfite in accordance with GOST 195-77

White spirit according to GOST 3134-78

Benzoic acid according to GOST 10521-78

Formic acid according to GOST 1706-78

Propionic acid according to TU TCP 11501-63

Acetic acid according to GOST 61-75

Sodium hydroxide according to GOST 4328-77

Potassium hydroxide according to GOST 4203-65

Sodium acetate according to GOST 199-78

Potassium acetate according to GOST 5820-78

Potassium nitrate according to GOST 4217-65

The compositions to be cleaned are: acidic oils (products of condensation of volatile and entrained with the air stream degradation products during the oxidation of sunflower oil into film-forming for drying oils of the “oxol” type at 120-160 ° C, as well as other vegetable oils, fats and their mixtures in this temperature regime, low-viscosity (up to 80 s with a VZ-4 viscometer at 20 ° C), the oxidants of sunflower and other vegetable oils, their mixtures with fats, as well as fish oil separately, solutions of oxidates and acid oils in various organic solvents, including mixed ones, are different washed washing compositions and extracts, etc.

Vegetable oil oxidates were obtained by liquid-phase oxidation of the latter in bubbler columns with air in a bubbler mode in the absence of salt catalysts at 100-160 ° C until a set of appropriate viscosities, depending on the nature of further use.

Some of the obtained oxidates were dissolved in white spirit or in some other solvent with the formation of ~ 55% (oxide type oil models) and ~ 75% solutions having a nominal viscosity of not more than 35 s using a VZ- viscometer. 4 at 20 ° C.

The process of the claimed method is as follows. The organic composition to be purified is analyzed for carbonyl compounds and acids. Based on the results of such an analysis, they decide whether an addition of carboxylic acid is needed and in what quantity. With a positive solution, such an additive is introduced, after which, and with a negative solution immediately, the working amount of the composition is placed in a bead mill. Then load the calculated amount of sodium sulfite and a stimulating additive. Glass beads are introduced into the reactor in advance. Mechanical stirring is turned on and this moment is taken as the start of cleaning. During the process, samples are taken and the residual content of carbonyl compounds and acids is monitored in them. As soon as the results of such control begin to meet the task, the stirring is stopped, the reaction mixture (suspension) is separated from the beads through a filter screen in the form of a metal mesh and poured into a settling tank or immediately allowed to filter or centrifuge. After separation of the solid phase, the purified and clarified composition is directed to the intended use. The solid phase is most often accumulated for the subsequent isolation of carbonyl compounds and (or) carboxylic acids from it. A new portion of the starting composition is loaded into the reactor with the remaining beads in it and purification is carried out as described above.

Example No. 1

In a bead mill with a stainless steel casing and a paddle mixer of the same material with a diameter of 80 mm and a height of 200 mm, 350 g of glass beads and 350 g of an organic mixture with a conditional viscosity of 19 s according to VZ-4 (20 ° C) containing 0.056 g are loaded -eq of carbonyl compounds and 0.058 g-equiv of acids. Acids are slightly larger than carbonyl compounds. The task is to completely remove both carbonyl compounds and acids. Therefore, sodium sulfite is taken in the ratio with acids 1.25: 1. 10 g of sodium sulfite is loaded (the content of the basic substance is 91.35%,), sodium acetate (× 3H ₂ O) in the amount of 0.140 g is introduced as a stimulant, mechanical mixing (rotation speed of a mechanical stirrer 1570 rpm) and this moment is taken as the beginning of the experiment. The initial temperature in the reaction zone is 14 ° C.

During the process, samples of the reaction mixture are taken, the liquid phase is separated from the solid phase by centrifugation, and the content of carbonyl compounds and acids in the liquid phase of the sample is determined. 20 minutes after the start of mixing, these compounds are in trace amounts. The degree of removal of carbonyl compounds and acids exceeded 98%.

Stop mixing in a bead mill. The reaction mixture at this point in time had a temperature of 19 ° C. It is poured through a metal mesh and thus separated from the glass beads, collecting the suspension in a centrifugation container. After carrying out the latter for 5 min, the liquid phase is separated from the precipitate, which is used for its intended purpose. The precipitate is collected in a separate storage tank for the subsequent isolation of carbonyl compounds.

Released bead mill is subjected to purification from the remnants of the processed composition, if necessary. In further work with related compositions, there is no fundamental need for such cleaning.

Examples No. 2-7

The reactor, the nature of the composition, the procedure for preparing the composition for processing, loading, carrying out the process and unloading the reaction mixture are similar to those described in Example 1. They differ in the ratio of the contents of carbonyl compounds and acids in the composition, the introduction of additional acid, its nature and amount, nature and amount of stimulating additive, time and temperature characteristics of the process, methods of separation of the solid phase from the final suspension. The results obtained are summarized in table 1. Designation: MK, UK, PC, BK - formic, acetic, propionic and benzoic acid; GN, HA, AN, AK, NK - sodium and potassium hydroxides, sodium and potassium acetates, potassium nitrate; О, Ф, Ц - sedimentation, filtration, centrifugation.

Table 1 Characteristics of the starting composition, loading, process and separation of the solid phase from the final suspension Example No. 2 3 4 5 6 7 Original composition: [> C = O] ₀ , g-equiv / kg 0.15 0.33 1.05 0.47 0.75 0.25 [-C (O) OH] ₀ , g-equiv / kg 0.05 0.17 0.53 0.48 0.85 0.04 VZ-4 viscometer viscosity at 20 ° С, s 14 16 19 thirteen 17 14 Additional acid: Nature MK UK PC - - BC amount, 10 ² n, g-eq 3,5 5.52 17.36 - - 6.62 Loading: composition without added acid, g 350 345 330 340 290 315 sodium sulfite, g 8.69 19.32 61.18 30.84 51.00 15,53 stoichiometric excess of sodium sulfite 1.20 1.23 1.28 1.37 1,50 1.43 Stimulating supplement: nature AK AN NK GN GK AN amount,% by weight of sulfite 1,0 2,5 3,7 2.9 4.0 1.9 The mass ratio of loading and glass beads 1: 1,1 1: 1,2 1: 1 1: 1.3 1: 2 1: 1,5 Temperature: initial, ° С 19 23 25 26 27 21 final, ° С 22 25 28 thirty thirty 24 The duration of the process, min 17 24 32 35 19 fifteen Degree of purification from carbonyl compounds,% 98 98 99 99 99 98 acids (including added),% ~ 100 98 98 98 98 98 The method of removing solid phase from the final suspension O Ts O Ts F F

Examples No. 8-13

The reactor, the procedure for preparing the composition for processing, loading, carrying out the process, unloading the reaction mixture are similar to those described in Example 1. They differ in the nature of the composition used, carbonyl compounds and acids in it, the stoichiometric excess of sodium sulfite, the nature and amount of the stimulating additive, the temperature and time characteristics of the process , the rotation speed of the mechanical stirrer in the bead mill, as well as the method of separating the solid phase from the final reaction mixture. The results obtained are summarized in table 2. Designations are given in table 2 of examples 2-7.

table 2 Characteristics of the starting composition, loading, process and separation of the solid phase from the final suspension Example No. 8 nine 10 eleven 12 thirteen Original composition: [> C = O] ₀ , g-equiv / kg 0.23 0.21 0.24 0.20 0.19 0.24 of which ketones (acetone, cyclohexanone), g-eq / kg 0.00 0.21 0.12 0.14 0,07 0.05 [-C (O) OH] ₀ , g-equiv / kg 0.13 0.12 0.11 0.08 0,07 0.05 VZ-4 viscometer viscosity at 20 ° С, s 16 eighteen 17 19 eighteen 17 Additional acid: nature BC BC MK MK UK PC amount, 10 n, g-eq 3.00 2.70 3.90 3.60 3.60 5.70 Loading: composition without added acid, g 300 300 300 300 300 300 sodium sulfite, g 11.90 10.86 12.41 11.17 10.62 13.41 stoichiometric excess of sodium sulfite 1.25 1.25 1.25 1.35 1.35 1.35 Stimulating supplement: nature AN AN NK NK AK AK amount,% by weight of sulfite 2,5 2,4 2,4 2,4 2,5 2,5 The mass ratio of loading and glass beads 1: 1.45 1: 1.45 1: 1.45 1: 1,5 1: 1,5 1: 1,5 Temperature: initial, ° С thirty thirty thirty 28 28 28 final, ° С 33 33 33 31 31 31

Continuation of table 2 Characteristics of the starting composition, loading, process and separation of the solid phase from the final suspension Example No. 8 nine 10 eleven 12 thirteen The speed of rotation of the mechanical stirrer, rpm 960 1440 1570 1570 1570 1440 The duration of the process, min 109 31 42 45 fifty 47 Degree of purification from carbonyl compounds,% 79 97 98 98 98 98 acids (including added),% 89 98 98 98 98 98 The method of removing solid phase from the final suspension F Ts Ts Ts O F

Examples No. 14-19

The reactor, the procedure for preparing compositions based on sunflower oil oxidates for processing, loading, carrying out the process, and unloading the reaction mixture are similar to those described in Example 1. They differ in the initial viscosity of OPM before dilution with white spirit and after dilution, the content of carbonyl compounds and acids in the composition for processing , the amounts of acetic acid and sodium acetate introduced, a stoichiometric excess of sodium sulfite, the temperature and time characteristics of the process, as well as the method of separation of solid zy of the final suspension. The results obtained are summarized in table 3

Table 3 Characteristics of the initial OPM, composition after dilution with white spirit, loading, carrying out the process and separating the solid phase from the suspension Example No. 14 fifteen 16 17 eighteen 19 The viscosity of the initial OPM, with a viscometer VZ-4 (20 ° C) 34 37 75 Outside of the appliance The viscosity of the composition for processing, with a viscometer VZ-4 (20 ° C) 34 37 fifteen 21 25 31 Content in the composition: [> C = O] ₀ , g-equiv / kg 0.09 0.14 0.06 0.15 0.14 0.17 [-C (O) OH] ₀ , g-equiv / kg 0.10 0.09 0.04 0.08 0.11 0.09 10 ² n CH ₃ COOH g-equiv 0.00 1.75 0.70 2.45 1.05 2.80 Loading amount of composition for processing, g 350 350 350 350 350 350

Continuation of table 3 Characteristics of the initial OPM, composition after dilution with white spirit, loading, carrying out the process and separating the solid phase from the suspension Example No. 14 fifteen 16 17 eighteen 19 sodium sulfite, g 6.28 8.79 4.06 10.14 8.11 12.31 stoichiometric excess of sodium sulfite 1.3 1.3 1.4 1.4 1,2 1,5 sodium acetate,% by weight of sulfite 1.9 1,0 2,5 3,1 4.0 2,8 The mass ratio of loading and glass beads 1: 1,5 1: 1,2 1: 1.3 1: 1,1 1: 1 1: 1.6 Temperature: initial, ° С fifteen 16 fifteen 17 twenty 24 final, ° С eighteen eighteen eighteen 19 22 26 The duration of the process, min 28 33 fifteen eighteen 17 21 Degree of purification from carbonyl compounds,% 97 97 98 98 98 98 acids (including added),% 96 97 98 98 98 98 The method of removing solid phase from the final suspension O O F O O F

The positive effect of the proposed solution is as follows:

1. Water is completely excluded from the process of purification of organic compositions from carbonyl compounds and acids, and, consequently, drying of the purified composition from moisture, which in some cases is of paramount importance.

2. The specified method allows you to clean the organic composition of many aldehydes, ketones and mixtures thereof and provides a fairly high degree of purification even at low initial contents of carbonyl compounds and acids.

3. The method is simple, does not require the use of external heat and any special and especially unique equipment.

4. The method does not exclude the utilization of recoverable carbonyl compounds and acids, provided that accumulation of the separated solid phases obtained by processing the suspensions is carried out.

5. The effectiveness and other characteristics of the proposed solution are significantly improved if it becomes one of the stages of the gross process for the preparation of compositions not containing carbonyl compounds and acids.

Claims (4)

1. A method of purifying complex organic liquid mixtures of carbonyl compounds and acids by treating them with sodium sulfite, characterized in that organic mixtures containing carbonyl compounds and carboxylic acids in a ratio of 1 g-equiv: 1 g-equiv or with an excess of acids, or with an excess of carbonyl compounds, in this case, before treatment with sodium sulfite, an amount of carboxylic acid is added to the initial mixture in such an amount as to bring the ratio of carbonyl compounds and acids to 1 g-equiv per 1 g-eq, and the treatment is carried out with solid sodium sulfite in a bead mill with a weight ratio of the composition and glass beads as a grinding agent 1: 1–2 and a mechanical stirrer rotation speed of at least 1440 rpm at a dosage of sodium sulfite 1.2-1 , 5 mol per 1 g-equiv of a carbonyl compound or an excess of acid in the presence of a stimulating additive until the carbonyl compounds or carbonyl compounds and acids are almost completely consumed. 2. The method according to claim 1, characterized in that as the added carboxylic acid, an acid is used that has as little molecular weight as possible and does not interfere in trace amounts with the use of the purified composition for its intended purpose. 3. The method according to claim 1, characterized in that as a stimulating additive take hydroxides and acetates of sodium and potassium and potassium nitrate in an amount of 1-4% by weight of sodium sulfite introduced, respectively. 4. The method according to claim 1, characterized in that in the case of the starting compositions with a relative viscosity of more than 37 s using a VZ-4 viscometer (20 ° C), they are diluted with an appropriate solvent before entering sodium sulfite.