RU2373182C2 - Method of producing malonate and manganese (ii) succinate - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing malonate or manganese (II) succinate, which can be used in different areas of chemical practice, in analytical control and scientific research, through direct reaction of a metal and its dioxide with carboxylic acid in the presence of an organic solvent and stimulating iodine additive in a vertical type bead mill with a high-speed mixer and glass beads as grinding medium, where manganese, its dioxide and carboxylic acid in the initial load are taken in molar ratio 1+x):1:(2+x) so as to obtain (2+x)m moles of salt, where x in the given molar ratio of reagents equals 0.4±0.1 for amber acid and 1.0±0.1 for malonic acid, and m is the number of moles of manganese dioxide in the load; iodine is taken in amount of 0.05 mol/kg of the reaction mixture after loading organic solvent and acid, but before loading manganese dioxide and metal. Total mass of acid, metal and its dioxide lies between 15 and 25% of the mass of the initial load, and ratio of mass of beads to mass of the load is 1:1. The process is started at room temperature and carried out under forced cooling conditions at temperature ranging from room temperature to 40°C while controlling by taking samples until exhaustion of all loaded reagents into the target salt, after which the process is stopped. The suspension of the final reaction mixture is separated from the beads and filtered. The product residue is washed with a liquid phase solvent and taken for purification from trace metal and its dioxide through recrystallisation, and the filtrate and washing solvent are returned to the repeated process.

EFFECT: process takes place at acceptable rates and ends with virtually complete consumption of all loaded reagents.

2 cl, 19 ex

Description

The invention relates to a technology for producing manganese salts of saturated fatty dicarboxylic acids and can be used in various fields of chemical practice, and analytical control and scientific research.

A known method for producing manganese succinate (RF patent No. 2174508), in accordance with which succinates of d-elements are obtained by the action of sulfate of the corresponding d-metal on the reaction solution of a mixture of succinic acid and sodium hydroxide in a molar ratio of 1: 2 at 80-85 ° C for 20-30 min, followed by cooling the reaction mixture to 10-15 ° C and separating the precipitated crystalline product by filtration, washing the precipitate with cold water (5-7 ° C) from sulfates and drying in a vacuum oven at a temperature of 35-40 ° C and a pressure of 20 mmHg.

The disadvantages of this method are:

1. Despite the fact that sodium succinate is not specifically isolated as an independent product in technological terms, the process remains two-stage, namely, the production of sodium succinate or a reaction solution and the exchange of sodium cation in the salt of the reaction solution to a d-metal cation in contact with sulfate of this metal .

2. Sodium hydroxide is easily flooded, which requires appropriate consideration when preparing the reaction solution; in the absence of the latter, the mixing of acid and alkali in a molar ratio of 1: 2 determines a certain excess of acid, which will have to be removed when cleaning the product.

3. In the process, a co-product of sodium sulfate is formed, which must be disposed of.

4. The solutions used cannot be concentrated to avoid obtaining a thickened product paste instead of an easily filtered suspension. A temperature of 80-85 ° C suggests heating mainly water as a solvent, which determines the high energy intensity of the process.

5. This process results in a large amount of wastewater requiring appropriate treatment and other costs.

Closest to the claimed is a method for producing manganese (II) acetate (RF patent No. 2294921), in accordance with which the specified salt is obtained by direct interaction taken in a molar ratio of 2: 1 metal and manganese dioxide with acetic acid in a solution of ethyl cellosolve, ethylene glycol, 1 , 4-dioxane, isoamyl or n-butyl alcohol in the presence of iodine additives. The process is carried out in a vertical type bead mill with a high speed paddle mixer and glass beads as a grinding agent. The concentration of acetic acid in the liquid phase is 3.4-5 mol / kg. The content of metal and its dioxide (solid reagents) in the load of 11.8% of the liquid phase. The mass ratio of the liquid phase and glass beads is 1: 1.5. The iodine content in the liquid phase is 0.025-0.070 mol / kg. The process begins at room temperature and lead to almost complete consumption of manganese dioxide. The salt suspension is separated from the main part of the unreacted metal and glass beads and sent for filtration. The filtrate is returned to the repeated process, and the precipitate is purified from metal impurities by recrystallization.

The disadvantages of this method are:

1. Acetic acid is monobasic, while malonic and succinic acids are dibasic, and noticeably stronger: pK _a for acetic acid 4.75, for malonic acid 2.86 and 5.70, succinic 4.21 and 5, 64. It is not at all obvious that these acids will react the same way under comparable conditions.

2. The indicated dicarboxylic acids are higher molecular in comparison with acetic acid and, moreover, under normal conditions are solid. In addition, they have different solubilities in various organic media. There is no reason to believe that they can be converted into a solution in the right solvents in the amount of 3.4-5.0 g-equiv / kg, as is easily done in the case of acetic acid.

3. The analyzed solution contains an excess of metal, from which it is necessary to separate the final reaction mixture, and to clear the product from its traces. In order not to carry out these operations in full, or even better to exclude them altogether, you need to remove excess metal from the initial load. And for this you need to know what real excess metal is needed and how much it affects the characteristics of the redox process. Most likely, this parameter depends on the nature of the acid, but how is currently unknown.

4. The salt of acetic acid mainly accumulates in the solid phase, which makes it possible to separate it by filtration. There is no certainty that this situation will continue in the case of malonic and succinic acids.

5. In the case of acetic acid, the criterion for stopping the process is the almost complete consumption of manganese dioxide. There is no reason to believe that this approach will continue in the transition to dicarboxylic acids.

6. The duration of the process with acetic acid is in the region of 100 minutes or more. At these speeds, the release of reaction heat slightly violated the isothermal or close to it process mode in the absence of forced cooling. It is not at all obvious that this situation will remain during the transition to malonic and succinic acids, where the rates of heat release can turn out to be noticeably large.

The objective of the proposed solution is to select such a molar ratio of manganese, its dioxide and acid in the initial charge, and also such conditions of the redox process that it proceeds at acceptable speeds and ends with almost complete consumption of all the loaded reagents in an acceptable time.

The problem is achieved by the fact that manganese, its dioxide and dicarboxylic acid in the initial load are taken in the molar ratio (1 + x): 1: (2 + x) based on the preparation of (2 + x) m moles of salt, where x in the above the molar ratio of the loaded reagents is 0.4 ± 0.1 for succinic acid and 1.0 ± 0.1 for malonic acid, am is the number of moles of manganese dioxide in the charge, iodine is dosed in the amount of 0.05 mol / kg of the reaction mixture after loading organic solvent and acid, but before loading manganese dioxide and metal, while the sum of the masses of acid, meth lla dioxide and take in the range of 15-25% by weight of the boot, and the mass ratio of the beads and loading 1: 1; the process starts at room temperature and is carried out under forced cooling in the temperature range from room temperature to 40 ° C under control by sampling the reaction mixture until all charged reagents are almost completely consumed in the target salt, after which it is stopped, the suspension of the final reaction mixture is separated from the beads and filtered, the precipitate of the product is washed with a solvent of the liquid phase and sent for purification from traces of metal and its dioxide by recrystallization, and the filtrate and washing solvent return t in a second process. In this case, n-propyl, n-butyl and iso-butyl alcohols, butyl acetate, xylene, white spirit and heptane are taken as an organic solvent of the liquid phase

Characteristics of the raw materials used

Reactive manganese according to GOST 6008-90

Manganese dioxide according to GOST 4470-79

Crystalline iodine according to GOST 4159-79

Malonic acid according to TU 6-09-2608-77

Succinic acid according to GOST 6341-75

n-Propyl alcohol according to GOST 9805-84

n-Butyl alcohol according to GOST 6006-78

iso-butyl alcohol according to GOST 9536-79

Butyl acetate according to GOST 8981-78

Heptane reference (TU 6-09-4520-77)

m-Xylene (TU 6-09-2438-77)

White spirit technical in accordance with GOST 3134-78.

The process of the claimed method is as follows. In a vertical type bead mill with a glass case and a high-speed mechanical paddle mixer made of durable and process-indifferent plastic and glass beads, the calculated quantities of beads and initial loading components, in particular a solvent of a liquid phase, dicarboxylic acid, stimulating additives of iodine, metal are loaded as a grinding agent and its dioxide. Turn on mechanical mixing and this moment is taken as the beginning of the process. During the process, samples are taken of the reaction mixture, including the components of the initial loading and the products of their transformation, in which the content of manganese salts and the residual content of manganese dioxide and acid are determined. As soon as the content of manganese salt is sufficiently close to the calculated value, the process is stopped. The reaction mixture is separated from glass beads and sent for filtration. The mixer, beads and mill body are washed with a solvent of the liquid phase, which is then used to wash the resulting salt precipitate. The filtered solid salt is sent to clean the remaining traces of the metal and its dioxide by recrystallization, and the filtrate and the washing solvent are returned to the repeated process.

Example 1

In a bead mill with a glass case with an inner diameter of 55 mm and a height of 104 mm, equipped with a high-speed (1440 rpm) paddle mixer made of durable textolite with a rectangular blade 52 × 40 mm, a reflux condenser and a liquid bath for forced cooling of the reaction mixture along the way of the process, 100 g of glass beads are loaded sequentially with bead diameters ranging from 1.5 to 2.8 mm, 80.73 g of n-butyl alcohol, 11.40 g of succinic acid, 1.27 g of iodine, 3.50 g of dioxide manganese and 3.10 g of manganese. Water is supplied to the cooling bath and reflux condenser and mechanical stirring is turned on. This moment is taken as the beginning of the process. The temperature of the reaction mixture at this moment was 18 ° C. During the process, the temperature in the reaction zone is monitored and samples of the reaction mixture are taken, in which the content of manganese (II) salt is determined, as well as residual amounts of acid and manganese dioxide. After 65 minutes, the content of manganese salts determined by the analysis turned out to be 0.962 mol / kg, which is close to the calculated value (0.967 mol / kg), and the temperature in the reaction zone was 29 ° C.

Repeated sampling and its analysis confirm the almost complete absence of unreacted manganese dioxide and acid in the reaction mixture.

Stop stirring the reaction mixture. The reaction mixture is separated from the glass beads by passing through a partition in the form of a mesh with mesh sizes of ~ 0.3 × 0.3 mm, and then filtered. The assembled reactor, the stirrer and the beads are rinsed with a working stirrer of 30 g of n-butyl alcohol. The resulting mixture is sent to washing the filter cake. The filtrate and the washing solvent are recycled and the product precipitate is sent for purification by recrystallization.

The product yield, excluding losses during purification, was 0.095 mol. The degree of acid use for salt formation is 98.2%.

Examples 2-7

The reactor, the nature of the reagents and the stimulating additive, the masses of the loads of each component and in general, the ratio of the masses of the load and glass beads, the order of loading of the components, the process and monitoring its progress, the criterion for the moment of termination of the process, the operation for separating the reaction mixture from the beads, the isolation of the product from the reaction mixture and its primary washing with the used solvent of the liquid phase are similar to those described in Example 1. They differ in the nature of the solvent used. The obtained characteristics of the process and product yield are summarized in table 1.

Table 1 Characteristics of loading, process and salt output Example No. 2 3 four 5 6 7 Liquid phase solvent n-propyl alcohol iso-butyl alcohol butyl acetate m-xylene White Spirit heptane Operating temperature range, ° С 18-28 18-27 18-31 18-24 18-23 18-20 The duration of the process, min 57 84 60 one hundred 130 180 Product yield (excluding losses during purification), mol 0,096 0,095 0,096 0,095 0,095 0,095 The degree of acid use on the target product,% 99.3 98.2 99.3 98.2 98.2 98.2

Examples 8-13

The reactor, the nature of the reagents and solvent, the mass of the load, its ratio to the mass of glass beads, the iodine content in the load, the order of loading of the components and the process, the choice of the moment of termination of the process, the sequence of operations for separating the reaction mixture from the beads, isolating the product, cleaning and returning it the liquid phase in the reverse process are similar to those described in example 1. They differ in the x value in the molar ratio of the reactants and the relative mass of the reactants in the initial load. The results obtained are summarized in table 2.

table 2 Characteristics of loading, process and product yield Example No. 8 9 10 eleven 12 13 The value of x in the molar ratio of reagents 0.30 0.45 0.50 0.40 0.40 0.40 Manganese dioxide loading, mol 0,0349 0.0480 0,0538 0,0444 0,0495 0,0554 The relative mass of reagents in the load,% 15.00 19.15 25.00 19.87 22.15 24.79 Operating temperature range, ° С 22-33 22-39 22-38 23-40 22-40 25-40 The duration of the process, min 70 71 75 68 72 73 Product yield (excluding losses during purification), mol 0,079 0,100 0,132 0.105 0.116 0.131 The degree of acid use on the target product,% 98.4 97.2 98.1 98.5 97.6 98.5

Examples 14-19

The reactor, the nature of the metal, oxide and solvent, the mass of the load, its ratio to the mass of glass beads, the iodine content in the initial load, the order of loading of the components of the reaction mixture and the process, the choice of the moment of its termination, the sequence of operations for separating the reaction mixture from beads, product isolation , its purification and return of the separated liquid phase to a repeated process are similar to those described in example 1. They differ in the use of malonic acid, the value of x in the molar ratio of the reactants and relatively mass of the reactants in the initial download. The results obtained are summarized in table 3.

Table 3 Characteristics of loading, process and product yield Example No. fourteen fifteen 16 17 eighteen 19 The value of x in the molar ratio of reagents 0.9 1,0 1,1 1,0 1,0 1,0 Manganese dioxide loading, mol 0,0303 0,0456 0,0476 0,0384 0.0411 0,0491 The relative mass of reagents in the load,% 15.00 23.24 25.00 19.57 20.93 25.00 Operating temperature range, ° С 22-36 22-35 22-32 24-40 24-39 24-34 The duration of the process, min 80 84 114 58 71 118 Product yield (excluding losses during purification), mol 0,086 0.134 0.145 0,112 0.121 0.144 The degree of acid use on the target product,% 97.8 98.1 98.4 97.4 98.1 98.0

The positive effect of the proposed solution.

1. The proposed method uses reagents, the bulk of the mass of which passes into the mass of the target product. Related products are water and hydrogen, the formation of which takes only a small part of the initial mass of the reactants. In addition, these related products do not require disposal and do not contaminate the target product.

2. In the proposed solution, there is no wastewater, the used liquid phase is returned to the repeated process and so can be repeated many times.

3. In the proposed process, there is no need to use heat supply. On the contrary, reaction heat has to be removed. In general, the process is low-energy.

4. This process does not require any sophisticated equipment, especially boiler inspection.

5. This process allows the use of a fairly large assortment of solvents.

Claims (2)

1. A method of producing manganese (II) malonate or succinate by direct interaction of a metal and its dioxide with a carboxylic acid in the presence of an organic solvent and a stimulating additive of iodine in a vertical type bead mill with a high-speed stirrer and glass beads as a grinding agent, characterized in that manganese , its dioxide and dicarboxylic acid in the initial charge are taken in a molar ratio
(1 + x): 1: (2 + x) based on the production of (2 + x) m moles of salt, where x in the molar ratio of charged reagents is taken 0.4 ± 0.1 for succinic acid and 1.0 ± 0.1 for malonic acid, am is the number of moles of manganese dioxide in the charge; iodine is dosed in an amount of 0.05 mol / kg of the reaction mixture after loading the organic solvent and acid, but before loading manganese dioxide and metal, while the sum of the masses of acid, metal and its dioxide is taken in the range of 15-25% of the mass of the initial load, and the mass ratio of the beads and the load is 1: 1, the process starts at room temperature and is carried out under forced cooling in the temperature range from room temperature to 40 ° С under control by sampling method until practically all quantitative expenditures of the loaded reagents are consumed -hand salt, whereupon it was stopped, the slurry of the final reaction mixture is separated from the beads and filtered, the product cake was washed with solvent and the liquid phase is sent for cleaning and metal traces dioxide, recrystallization, and the filtrate and the washing solvent is recycled to the second process. 2. The method according to claim 1, characterized in that n-propyl, n-butyl and iso-butyl alcohols, butyl acetate, xylene, white spirit and heptane are taken as an organic solvent of the liquid phase.