RU2414451C1 - METHOD OF PRODUCING MANGANESE (II) n-AMINOBENZOATE - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing manganese (II) n-aminobenzoate through direct reaction of metal with carboxylic acid in the presence of an oxidising agent. The oxidising agent used is manganese peroxide in molar ratio to metal equal to 1:1-1:3 in total molar load of metal-containing reagents equal to 0.75-1.25 mol/kg and in molar ratio with acid equal to 1:(1.95-2.0). The liquid-phase solvent used is butyl acetate. The stimulating additive used is molecular iodine and solid manganese n-aminobenzoate, taken in amount of 0.01-0.10 mol/kg and 0-0.035 mol/kg respectively. Loading is done successively: glass beads in weight ratio to the rest of the load equal to 1.5:1, butyl acetate, carboxylic acid, metal, peroxide thereof and molecular iodine, after which the components are stirred and solid manganese carboxylate is added. The process is carried out with spontaneously increasing temperature in the range of 20-45°C and monitoring via sample collection and analysing the samples for content of the end product until achieving output of the calculated value of 98% or more. The process is then stopped, the reaction mixture is separated from the glass beads, cooled to 10-15°C, kept at that temperature for 1.5-2.0 hours and then filtered. The residue is then removed from the filter and taken for purification through recrystallisation. The filtrate then accumulates and then undergoes simple distillation; the distilled solvent is then returned to the reverse process and an additional amount of the end product is then extracted from the still after cooling and filtration.

EFFECT: high output of the end product, improved environmental properties of the process and low power consumption.

2 cl, 16 ex, 1 tbl

Description

The invention relates to a technology for producing manganese (II) carboxylates and can be used in various fields of laboratory and industrial practice, in scientific research, as well as in analytical control.

There is a method of producing the basic formate or indium acetate by direct interaction of the metal with the corresponding fatty acid in the presence of hydrogen peroxide as a metal oxidant, followed by the isolation of the target carboxylate by known methods (AS USSR No. 454198).

The disadvantages of this method are:

1. There is no reason to believe that there is a direct analogy in metal-oxidizer-carboxylic acid systems in the transition from indium-hydrogen peroxide-acetic acid to manganese-manganese peroxide-n-amino-benzoic acid. Here, each component of the system can make such significant contributions to the macrokinetic and other characteristics of the process that a fully operational process in one embodiment will turn into completely unworkable in the second. In other words, each component of the gross system under consideration should be evaluated for many characteristics separately and in combination, not only on a qualitative, but also on a strict quantitative level. In such a complex gross system, transfer, especially automatic, of the characteristics of one pair of reagents to another, not to mention the triplets of reagents, is practically impossible and unacceptable.

2. In the process under consideration, no specific requirements for the reaction apparatus in which it is conducted are formulated. Nevertheless, it is the correct choice of the reaction apparatus in the considered type of heterogeneous heterophase processes that is the prerequisite that determines the operability of the process as such.

3. In the cited process, temperatures of 80-100 ° C are used, which must be maintained by supplying external heat. This significantly increases the energy intensity of the process and degrades its environmental performance.

Closest to the claimed is a method of producing manganese (II) salicylate (RF patent No. 2331629, publ. 08.20.2008, BI No. 23) by reacting manganese with salicylic acid in the presence of manganese dioxide as an oxidizing agent, stimulating the addition of iodine and organic liquid phase, in in particular heptane, or m-xylene, or chlorobenzene, or white spirit, or butyl acetate in a bead mill, while the mass ratio of loading to glass beads is 1: 1.5, manganese dioxide is loaded in a molar ratio with acid of 1: (4.0 ÷ 4.2) and with metal 1: (1.9 ÷ 2.3), and soda neigh salicylic acid and iodine in the feed is 0.8 ÷ 2.2 mol / kg and 0.04 ÷ 0.07 mol / kg, respectively. The loading is carried out in the sequence: glass beads, a solvent of the liquid phase, acid, iodine and then the metal and its dioxide. The process begins with the inclusion of mixing and lead to almost complete consumption of manganese dioxide as a reagent in the deficiency. Next, the reaction mixture is separated from glass beads, after which the bulk of the product is isolated by filtration.

The disadvantages of the described method are:

1. Although manganese dioxide and peroxide have the same gross formula of MnO ₂ , these are completely different oxidizing agents. In this case, when converted to the target carboxylate, manganese in dioxide should reduce the oxidation state from 4 to 2, while manganese peroxide should not change its oxidation state.

2. n-Aminbenzoic and salicylic acids are different in their properties: they have different substituents, which are located in different places in relation to the carboxyl group. There is no reason to believe that they will be close in performance to the gross redox process under consideration.

3. There is no reason to believe that a specific reaction medium (solvent of the liquid phase) and a stimulating additive in both cases will be favorable, not to mention the quantitative characteristics of these issues.

4. There is no reason to believe that salicylate and n-aminobenzoate in their physical properties, in particular, on adhesion to the metal surface, solubility in reaction mixtures and in solvents of the liquid phase, etc. will be similar to each other and have close dynamics of changes in key characteristics during the process. As a result, there is no reason to believe that manganese n-aminobenzoate, like manganese salicylate, will accumulate mainly in the suspended solid phase, which can be easily separated by simple filtration.

5. In the cited method, the filtrate and the washing solvent are returned to the repeated process without any processing, which is a convenient way to utilize the bulk of the reaction mixture. There is no reason to believe that such a method of disposal will be possible upon receipt of manganese n-aminobenzoate.

The objective of the proposed solution is to select such a load of the reaction mixture and ranges of variation of the molar ratios of the components in it, as well as other conditions for the gross oxidation-reduction process, which would ensure practically quantitative transformations of manganese and its peroxide, as well as loaded n-aminobenzoic acid into the corresponding carboxylate, predominantly accumulating in the solid phase and separated from the rest of the reaction mixture by simple filtration.

The problem is achieved in that in the proposed method for producing manganese n-aminobenzoate by direct interaction of a metal with a carboxylic acid in the presence of an oxidizing agent, an organic liquid phase and a stimulating additive in a bead mill, manganese peroxide in a molar ratio of 1: 1-1 is used as an oxidizing agent : 3 with a total molar loading of metal-containing reagents 0.75-1.25 mol / kg and their molar ratio with acid 1: (1.95 ÷ 2.0), butyl acetate is taken as the solvent of the liquid phase, and as a stimulating additive molecular iodine and solid manganese n-aminobenzoate in an amount of 0.01-0.10 0-0.035 mol / kg, respectively; The loading is carried out in the sequence: glass beads in a mass ratio with the remaining loading of 1.5: 1, butyl acetate, carboxylic acid, metal, its peroxide and molecular iodine, then they are mechanically mixed, solid manganese carboxylate is introduced and the process is carried out at a spontaneously rising temperature in the range of 20-45 ° C and control by sampling and analyzing them for the content of the target product until reaching 98% or more yield from the calculated value, after which the process is stopped, the reaction mixture is separated from glass beads, cooled to 10-15 ° C, kept at this temperature for 1.5-2.0 hours, and then filtered; the precipitate is removed from the filter and sent for purification by recrystallization, and the filtrate is accumulated and subjected to simple distillation, the distilled solvent is returned to the reverse process, and an additional amount of the target product is isolated from the cube after cooling and filtering.

In this case, the addition of solid manganese n-aminobenzoate is introduced after 0.5-3.5 min after stirring in the bead mill.

Characteristics of the raw materials used

Reactive manganese according to GOST 6008-90.

Manganese peroxide according to GOST 4470-48

Crystalline iodine according to GOST 4159-79.

Butyl acetate according to GOST 8981-78.

n-Aminobenzoic acid according to TU 6-14-655-80.

Manganese n-aminobenzoate was obtained in previous experiments, purified by recrystallization from a solution of n-aminobenzoic acid in butyl acetate, and dried to constant weight.

The process of the claimed method is as follows. The vertical bead mill, equipped with a reflux condenser, a high-speed shovel-type mechanical stirrer and forced cooling of the casing with running cold water, introduces the calculated quantities of glass beads, butyl acetate, n-aminobenzoic acid, manganese, its peroxide, and molecular iodine. Mechanical stirring of the bead mill is turned on, and cold running water is supplied to the reflux condenser and to cool the reactor through the side walls of the casing. An additive of solid manganese n-aminobenzoate is added and the process is conducted so that the temperature along its course is in the range of 20-45 ° C. During the process, samples of the reaction mixture are taken, which are analyzed for their product content and residual acid. As soon as the product content exceeds 98% of the calculated value, the process is stopped: mechanical stirring of the bead mill is stopped, and the supply of cooling water is stopped. The reactor vessel is disconnected from its cover, removed from the socket of the frame frame, after which its contents are poured into a receiving funnel of the filtering unit with a mesh with mesh sizes of 0.3 × 0.3 mm as a filter partition. A suspension of the reaction mixture falls into the receiving tank, and the beads remain on the grid. It is carefully removed and returned to the reactor, the installation is reassembled, a certain amount of butyl acetate is introduced, mechanical stirring is activated for 5-10 minutes and the beads, stirrer and other elements of the reactor are washed from the residual reaction mixture. In parallel, a container with a suspension of the reaction mixture is sent to a cooling chamber for cooling, and instead of it, another container is placed in which the washing solvent is collected when the beads are again separated from it. The container with the washing solvent is separated from the filtration unit and sent to a refrigerating chamber.

After cooling to a temperature of 10-15 ° C and holding in this state for 1.5-2 hours, the reaction mixture is filtered, the precipitate is removed from the filter and sent to recrystallization. And the filtrate is accumulated to a certain amount, after which it is subjected to simple distillation. The residual solvent is returned to the loading of the repeated process, and the cube is allowed to cool slowly. The solid phase which has precipitated from it is filtered and purified by recrystallization, and the filtrate from the cube is combined with the filtrate of subsequent experiments as part of accumulation for another simple distillation.

The solid phase of the cooled wash solvent is also filtered and combined with the filter cake of the main reaction mixture until it is recrystallized. And the filtrate thus obtained is used repeatedly (and repeatedly) to wash the beads, stirrer and other elements of the reactor from the residues of the reaction mixture.

Example No. 1.

In a vertical type bead mill with a glass case in the form of a glass with a flat bottom with an inner diameter of 54.3 mm, a wall thickness of 3.7 mm and a height of 147 mm, equipped with a high-speed (1560 rpm) paddle mixer with a blade size of 53.3 × 49 × 3.5 mm from PCB, a reflux condenser, pockets for a sampler and temperature measurement (made in a plastic cover), as well as a cooling water bath with cold running water, 150 g of glass beads, 61.00 g of butyl acetate are sequentially loaded into as a solvent eating liquid, 29.86 g of n-aminobenzoic acid, 3.02 g of manganese, 4.78 g of manganese peroxide, 1.27 g of molecular iodine. The reactor vessel is connected to the lid and mounted in the corresponding socket of the frame frame. Water is supplied to the reflux condenser, a cooling water bath is brought in from below, mechanical stirring is turned on, this moment is taken as the beginning of the process. After 1.5 minutes, without stopping stirring, 0.07 g of purified and dried solid manganese n-aminobenzoate was introduced into the reactor and the process was continued, controlling its progress by sampling and determining the amount of accumulated manganese carboxylate and unreacted acid in them. Based on the data of the specified control, the dependence of the product yield on the time course of the process is built, which in this case corresponded to the following data.

Product yield in% of the calculated value. 25 fifty 75 98.7 Time to reach, min 3 7 21 43 The temperature of the reaction mixture, ° C 22 33 41 37

Upon reaching the last value of the product yield, the process of producing manganese n-aminobenzoate is stopped, for which mechanical stirring is stopped and the water supply to the reflux condenser and to the cooling bath are turned off. The latter is lowered down and the bead mill body with beads and the reaction mixture is removed from the nest of the frame frame. First, it is disconnected from the lid and slightly lowered, allowing the reaction mixture to drain from the blade and shaft of the mixer. Then the contents of the reactor are poured into a receiving funnel of the node for separating the reaction mixture from beads with a mesh with mesh sizes of 0.3 × 0.3 mm as a filter partition. The suspension of the reaction mixture fails, and then flows into the receiving container, and the beads remain on the grid. It is carefully removed and returned to the reactor vessel. The latter is placed in its nest in a frame frame, the installation is reassembled, 40 g of butyl acetate are introduced into the reactor and stirring is continued for 5 minutes. During this time, the receiving capacity of the glass bead separation unit is changed to a new one. Then, the stirring is stopped and the operation of separating glass beads is repeated, but already from the washing solvent and the residues of the reaction mixture. During it, the filter baffle of the node in question in the form of a grid and the receiving funnel of the node itself are freed from the residual reaction mixture.

The reaction mixture separated from glass beads is placed in a refrigerator, where it is cooled to 13 ° C and maintained at this temperature for 2 hours. Then it is filtered. The precipitate is carefully squeezed out, removed from the filter and sent for purification by recrystallization. All work is performed in such a way that at each stage it is possible to draw up a material balance. This gives a clear idea of the distribution of the product between the individual phases.

Do the same with the wash solvent. These operations are carried out separately. The filtrates of the reaction mixture (PC) and the wash solvent are not mixed. And precipitation is combined before they are cleaned.

PC filtrates are collected from several similar experiments and then subjected to simple distillation. About 70% of the solvent present in them is distilled off, which, after checking for cleanliness, is returned to the batch process again. Cuba is allowed to slowly cool to room temperature and remain in such conditions for 10 hours. After that, the solid phase of the product is filtered off, squeezed on the filter and sent for purification by recrystallization, and the filtrate is sent to accumulation for the next simple distillation.

The wash solvent filtrate is used to wash the beads and the reactor after another experiment.

(в молях).The yield of product separated by filtration was 91% of the calculated value. When filtering the cube from simple distillation, it increased to 95%. According to the analysis of the resulting reaction mixture, it amounted to 98.5%. The calculated value for the almost complete conversion of n-aminobenzoic acid to a carboxylate as a reagent in the deficiency should be 99% of

(in moles).

Examples No. 2-16.

, а также суммой мольных дозировок марганецсодержащих реагентов, т.е.

в исходной загрузке, мольным соотношением n-аминобензойной кислоты и суммы металла и его пероксида, диапазонами варьирования йода и твердого n-аминобензоата марганца в качестве стимулирующих добавок, температурой PC по ходу процесса, температурой охлажденной реакционной смеси и выдержкой при такой температуре перед фильтрованием, а также временем ввода стимулирующей добавки твердого карбоксилата марганца. Указанные различия и другие характеристики таких вариантов сведены в таблице.The reactor, the starting reagents, the solvent of the liquid phase, stimulating additives, the sequence of operations when loading the components of the reaction mixture, the ratio of the masses of the reaction mixture and glass beads, the sequence of operations of the process, separating the reaction mixture from beads, isolating the product from the reaction mixture and controlling them are similar, described in example 1. They differ in the molar ratio of the contents of manganese and its peroxide, i.e.

as well as the sum of molar dosages of manganese-containing reagents, i.e.

in the initial charge, the molar ratio of n-aminobenzoic acid to the sum of the metal and its peroxide, ranges of variation of iodine and solid n-aminobenzoate of manganese as stimulating additives, the PC temperature during the process, the temperature of the cooled reaction mixture and holding at that temperature before filtering, and also the time of administration of the stimulating additive of solid manganese carboxylate. These differences and other characteristics of such options are summarized in the table.

The positive effect of the proposed solution is:

1. In the process under consideration, a high percentage of the mass transfer of the starting reagents (metal, its peroxide and acid) to the mass of the target product is achieved. A related product is water, which is not considered to be environmental pollution and cannot be turned into wastewater in its quantities. All this, taking into account low flow temperatures, characterizes the proposed process as low-waste, low-energy and generally environmentally friendly.

2. In the proposed solution, the bulk of the product accumulates in the solid phase and is separated by simple filtering, which helps to increase the environmental characteristics of the process and reduce its energy intensity. The technological scheme of the process and its hardware design are simplified.

3. The water formed as a by-product does not require its isolation and disposal.

4. There is no boiler monitoring equipment in the hardware design of the process. The duration of the process in most cases is within 1 hour.

5. Use fairly simple methods of current control and easily determine the moment of termination of the process.

Table Characteristics of the load, process, the resulting reaction mixture Example No. 2 3 four 5 6 7 8 9 10 eleven 12 13 fourteen fifteen 16

, моль/моль

mol / mol 1: 1,5 1: 2.5 1: 3 1: 1 1: 1 1: 1 1: 1,2 1: 1,2 1: 1,2 1: 1,2 1: 1,2 1: 3 1: 3 1: 3 1: 3

mol / kg U 1,1 1,1 0.75 0.90 1.25 1,0 1,0 1,0 1,0 1,0 1,2 1,2 1,2 1,2

mol / kg 2.17 2.18 2.20 1,50 1.80 2,50 1.99 1.98 1.97 1.96 1.95 2,31 2,33 2,35 2,36

mol / kg 0.05 0.05 0.05 0.05 0.05 0.05 0.00 0.01 0,03 0.05 0.10 0.04 0.04 0.04 0.04

mol / kg 0,021 0,021 0,021 0,03 0,03 0,03 0,03 0,03 0,03 0,03 0.01 0,000 0.015 0,029 0,035 The input time of the addition of solid product, min from the beginning of mixing in a bead mill 1,5 1,5 1,5 2.0 2.0 2.0 2.5 2.5 1,0 1,0 0.08 - 3,5 2,3 0.5 The time to reach the product yield (in%) from theoretical, min 25 3 3 four 5 four 3 9 5 3 3 3 5 four four four fifty 7 8 8 12 9 6 55 29th 7 7 10 26 8 8 8 75 24 25 22 40 26 19 200 82 eighteen fourteen 40 88 23 17 twenty

98 and more (indicated in brackets) 53 (98.5) 57 (99) 41 (99) 88 (99) 63 (99) 51 (99) 413 (98) 143 (98) 48 (98) 36 (98) 95 (97) 174 (96) 66 (97) 37 (98) 48 (98) The temperature in the reaction zone at the time of reaching the product yield (in%) from the theoretical, ° C 25 24 22 22 twenty 23 26 21 24 27 28 27 23 23 24 23 fifty 31 33 34 26 29th 41 23 26 36 37 31 25 thirty 32 31 75 40 42 43 34 37 45 23 28 44 45 38 26 36 39 38 98 and more 35 36 37 29th 31 40 23 26 38 40 33 24 33 39 36 The duration of the process for producing manganese carboxylate, min 55 59 43 92 65 54 425 155 fifty 42 one hundred 182 72 43 55 The mass of the washing solvent, g 41 43 45 39 43 42 38 37 44 43 42 40 41 43 42 The duration of washing the beads and reactor elements from the remains of the reaction mixture, min 8 7 9 8 5 10 9 6 8 9 6 5 8 7 8 Chilled PC temperature, ° C 10 12 10 13 fifteen 10 eleven 12 13 fourteen 13 fifteen eleven 13 fourteen

The exposure of the cooled PC at a stable temperature before filtering, hour 1,5 1,6 1,5 1.7 2.0 1,5 1,6 1.7 1.7 1.8 1.8 2.0 1.8 1.9 1.9 The output of the product separated by filtration,% of the calculated value 90 89 91 83 89 92 81 86 88 91 84 84 91 92 92 The product yield, taking into account extracted from the cube,% of the calculated value 95 93 95 87 94 96 88 93 94 95 90 88 95 95 94 % of achievement of the calculated value according to the results of current control and balance measurements 98.5 99 99 99 99 99 98 98 98 98 97 96 97 98 98

Claims (2)

1. The method of producing manganese (II) n-aminobenzoate by direct interaction of a metal with a carboxylic acid in the presence of an oxidizing agent, characterized in that manganese peroxide is used as an oxidizing agent in a molar ratio with the metal in the range of 1: 1-1: 3 with a total molar loading metal-containing reagents 0.75-1.25 mol / kg and their molar ratio with acid 1: (1.95 ÷ 2.0), butyl acetate is taken as the solvent of the liquid phase, and molecular iodine and solid manganese n-aminobenzoate are taken as a stimulating additive in the amount of respectively 0.01-0.10, 0-0, 035 mol / kg, the loading is carried out in the sequence: glass beads in a mass ratio with the remaining loading of 1.5: 1, butyl acetate, carboxylic acid, metal, its peroxide and molecular iodine, after which they include mechanical stirring, solid manganese carboxylate is introduced and the process is carried out when the temperature rises spontaneously in the range of 20-45 ° С and is controlled by the sampling method and analyzing them for the content of the target product until 98% or more of the calculated value is reached, after which the process is stopped, the reaction mixture is separated they ate from glass beads, cooled to 10-15 ° C, kept at this temperature for 1.5-2.0 hours, and then filtered; the precipitate is removed from the filter and sent for purification by recrystallization, and the filtrate is accumulated and subjected to simple distillation; the distilled solvent is returned to the reverse process, and an additional amount of the target product is isolated from the bottom after cooling and filtering. 2. The method according to claim 1, characterized in that the addition of solid manganese n-aminobenzoate is introduced after 0.5-3.5 minutes after stirring in the bead mill.