RU2424225C1 - Method of producng basic copper (ii) acetate - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method involves reaction of a metal oxide with an acid in a bead mill in the presence of a stimulant. The process takes place in the presence of a liquid phase, the solvent of which is distilled water. Copper oxide is added in amount of 1.8-3.3 mol/kg in molar ratio to acetic acid equal to (1:1.7)-(1:2.1). The stimulant is added in amount of 0.05 mol/kg. Addition is performed in the following sequence: glass beads, liquid phase solvent, acetic acid, stimulant and copper (II) oxide, in molar ratio of the glass beads to the rest of the material equal to (1:1)-(1.5:1). Further, the material undergoes mechanical mixing and the process is carried out while constantly cooling in temperature range of 20-45°C until almost complete conversion of the loaded copper (II) oxide into a salt. Mixing and cooling are then stopped. The suspension of the reaction mixture is then separated from the glass beads. This suspension is mixed with washing water with reaction mixture residue, left for 1-2.5 hours and filtered. The product residue is thoroughly squeezed and taken for purification via recrystallisation, and the filtrate is returned to repeated process.

EFFECT: invention increases output and selectivity of the method of producing copper acetate.

2 cl, 9 ex, 2 tbl

Description

The invention relates to a technology for the production of copper (II) salts and can be used in various fields of chemical and other types of practice, in scientific research and in analytical control.

It is known to obtain the basic copper (II) acetate (copper-copper core) Cu (OH) ₂ · (CH ₃ COO) ₂ Cu · nH ₂ O (I. L. Knunyants. Chemical encyclopedia. T.2. M.: Soviet encyclopedia, 1990, p.671) by reacting copper, copper (II) oxide, copper (II) hydroxide or basic copper carbonates with acetic acid in the presence of air.

The disadvantages of this method are:

1. The redox process (copper - reducing agent, oxygen - oxidizing agent) in the presence of oxide, hydroxide or basic copper (II) carbonates is complex and difficult to control. At least some of the loading compounds (in particular, hydroxide and basic carbonates) are able to directly interact with the acid to form the indicated product. Such a combination of processes is not justified by anything and in terms of expediency is not at all obvious.

2. The process under consideration is not defined in any way in terms of the nature and quantity of the liquid phase, as well as the reactor in which it is carried out.

3. There is no clarity in the molar ratios of copper-containing and other reagents in the initial loading, in the ways of controlling the process, relative to the depth of its course, in the methods of isolation and purification of the target product.

Closest to the claimed is a method of tribochemical production of metal-containing soap components of fatliquoring mixtures (RF patent No. 2092533, publ. 10.10.1997, BI No. 28), in accordance with which salts of transition and other metals are obtained by direct interaction of metal oxides, hydroxides and carbonates I-VIII groups of the Periodic system with C ₇ and higher carboxylic acids, both individually and in the form of compositions and waste containing these acids, in the presence of an oil component and a solvent under conditions of fine grinding of the solid phase with the system during the process in a bead mill at 20-60 ° C for 10-40 minutes in the presence of 1-2% by weight of water and 0.05-0.1% by weight of a tribochemical catalyst, which use nitrogen-containing compounds as the best of which are ammonium and alkali metal nitrates, secondary and tertiary amines and acid amides. At the same time, paraffinic and aromatic hydrocarbons, their technical mixtures and AML oil are used as a solvent. An oil component, liquid components of acid-containing compositions, water and a tribochemical catalyst are introduced into it and, with vigorous stirring, all of the above are converted into a solution into which the metal-containing reagent is dosed, and the process of obtaining the target product is conducted.

The disadvantages of this method are:

1. It uses C ₇ and above, i.e. fairly high molecular weight carboxylic acids. It is not at all obvious that the above process conditions will be acceptable for similar reactions with lower molecular weight acids.

2. In the cited method there are no redox transformations. However, a restriction on the molecular weight of the carboxylic acid is indicated. It is possible that similar transformations with lower molecular weight acids are possible only with the parallel occurrence of the corresponding redox transformation, as proposed in the analogue considered above. Such an assumption is not obvious and requires experimental confirmation or a reliable refutation.

3. In the method under consideration, paraffinic or aromatic hydrocarbons, as well as their technical mixtures, are used as a solvent of the liquid phase. There is no reason to believe that these solvents will turn out to be favorable in the transition to lower molecular acids as reagents for the interaction with metal oxides, hydroxides and carbonates, including copper.

4. The same can be said about the nature and amount of the tribochemical catalyst or stimulant.

5. The transition to lower molecular weight acids as reagents can significantly affect the feasibility of introducing water additives into the initial reaction mixture. Moreover, when it is not clear whether the introduced water should at least partially be in the form of an independent, albeit very small phase, or should it completely go into solution and affect the solubility of the tribochemical catalyst and other components in it.

6. The same can be assumed with respect to the oil component of the initial charge. It is possible that its input is needed from the point of view of obtaining the components of the fatliquoring compositions. And changing the area of use of salts obtained in this way to others can automatically make the oil component practically unnecessary and completely exclude it from the initial load.

The objective of the proposed solution is to select such conditions for the process of interaction of copper (II) oxide with acetic acid, which would ensure high yield and selectivity at room temperature and close to it, as well as the rates of obtaining basic copper (II) acetate acceptable for practical purposes.

The problem is achieved in that the process is carried out in the presence of a liquid phase, the solvent of which is distilled water, copper oxide is loaded in an amount (1.8: 3.3) mol / kg in a molar ratio with acetic acid (1: 1.7) ÷ (1: 2,1), the stimulating additive is dosed in an amount of 0.05 mol / kg, the loading is carried out in the following sequence: glass beads, water, acetic acid, stimulating additive and copper oxide (II) in the weight ratio of glass beads and the rest of the load (1: 1) ÷ (1.5: 1), then include mechanical stirring e and carry out the process with continuous cooling in the temperature range of 20-45 ° C until the charged copper (II) oxide is almost completely consumed in the salt, after which stirring and cooling are stopped, the suspension of the reaction mixture is separated from glass beads, this suspension is mixed with wash water with the rest of the reaction mixture is left for 1.0-2.5 hours and filtered, the product precipitate is carefully squeezed out and sent for purification by recrystallization, and the filtrate is returned to the loading of the repeated process.

In this case, molecular iodine, potassium iodide or bromide, barium chloride or thiourea are used as a stimulating additive.

Characteristics of the raw materials used:

Copper oxide (II) according to GOST 16539-79,

Glacial acetic acid according to GOST 61-75,

Distilled water according to GOST 6709-72,

Crystalline iodine according to GOST 4159-79,

Potassium iodide according to GOST 4232-74,

Potassium bromide according to GOST 4160-74,

Barium chloride according to GOST 4108-72,

Thiourea according to GOST 6344-73.

The process of the claimed method is as follows. The vertical type bead mill, equipped with a reflux condenser, a high-speed paddle mixer and a cooling water bath that is easily moved along the longitudinal axis of the reactor, introduces the calculated amounts of glass beads, distilled water, acetic acid, stimulating additives, and copper (II) oxide of various origins. Mechanical stirring is switched on, a water cooling bath is brought in such a way that the reactor vessel at least 1/2 of its height is immersed in it, and cooling water is supplied to the reflux condenser. The process is conducted so that the temperature of the reaction mixture does not exceed 45 ° C. Monitoring the course of the process is carried out by the method of sampling and determining the contents of the accumulated product in them. As soon as the degree of consumption of copper oxide (II) exceeds 98%, the process is stopped by stopping the mechanical stirring. Turn off the supply of cooling water to the reflux condenser, lower the cooling bath so that the reactor vessel is out of it. The reactor vessel is disconnected from its cover and lowered down to the frame frame so that the lower edge of the paddle mixer is higher than the level of the reaction mixture in the reactor vessel. In this position, leave the reactor for some time, allowing the remaining reaction mixture to drain from the blade and shaft of the mixer.

Next, the reactor vessel is removed from the frame frame nest, and its contents are poured into a receiving funnel of the separation unit for the suspension of the reaction mixture from glass beads with a mesh with mesh sizes of 0.3 × 0.3 mm as a filter partition. The beads remaining on the grid are carefully removed and returned to the reactor vessel. The latter is placed in its nest in a frame frame, connected to the lid and carry out all the necessary operations to assemble the installation into working position. Next, a certain amount of distilled water is introduced, mechanical stirring is switched on, and beads and internal surfaces of the blade body and shaft and other reactor elements are washed from the remains of the reaction mixture. After this operation is completed, stirring is stopped and the beads are re-separated from the washing solvent, collecting the latter in a container with a previously separated suspension of the reaction mixture. The suspension and the washing solvent are thoroughly mixed and left to stand for 1.5-2 hours, after which they are filtered. The product precipitate on the filter is carefully squeezed and sent for purification by recrystallization, and the filtrate is analyzed and returned to the loading of the repeated process.

Example 1

In a vertical type bead mill with a glass case in the form of a thick-walled cup with an internal diameter of 52.1 mm and a height of 129 mm with a flat bottom and a high-speed paddle mixer (1560 rpm) with a 51 × 49 × 3.5 mm blade made of PCB, equipped with a reverse condenser refrigerator, pockets for sampler and temperature measurement (access to the return condenser refrigerator and these pockets, as well as the stuffing box for the mixer, are located in the thick-walled cover of the mill from the PCB), as well as easily moving along the longitudinal th axis of the reactor cooling water bath with running cold water and successively charged with 100 g of glass beads, 46.5 g of distilled water, 19.7 g of acetic acid, 1 g of iodine and 12.8 g of copper oxide (II). The reactor vessel is placed in its nest in the frame frame, connected to the reactor lid, the scrolling of the mixer shaft is checked, the cooling bath is brought in from below so that the mill body is submerged to 0.8-0.9 of its height, cooling water is supplied to the bath and into reflux condenser, include mechanical stirring and this moment is taken as the beginning of the process. The initial temperature of the reaction mixture is 21 ° C. The process is conducted in such a way that the temperature of the reaction mixture does not exceed 45 ° C, which is achieved by changing the degree of immersion of the reactor vessel in a cooling bath and by varying the flow rate of cooling water. During the process, without stopping mechanical stirring, samples of the reaction mixture are taken in which the content of the accumulated basic copper (II) acetate and the remaining acetic acid are determined. Based on these data, the dependence of the product yield on the process time is built. In this example, these data are summarized in table 1.

Table 1

Product yield in% of theoretical 25 fifty 75 96.5 Time to reach, min 90 160 220 300 The temperature of the reaction mixture at the indicated moment, ° C 28 35 42 36

When the results of the analysis exceed the 96.5% yield of the product, the process of its production is stopped, the mechanical stirring of the bead mill is stopped, the supply of cooling water to the reflux condenser and the bath is stopped, the latter is lowered down until the entire reactor vessel is higher, disconnect lids and lower it down so that the lower lid of the stirrer blade is above the reaction mixture. Stand in this position for 3 minutes, allowing the reaction mixture to drain from the surfaces of the blade and shaft of the mixer. After that, the case with the beads and the reaction mixture is removed from the reactor socket and its content is poured into a funnel to separate the reaction mixture from glass beads with a mesh with mesh sizes of 0.3 × 0.3 mm as a filter partition. The beads are carefully removed from the net and returned to the reactor vessel. The apparatus is reassembled, 30 g of distilled water is introduced, mechanical stirring is switched on and the beads, as well as the surfaces of the casing, mixer and its shaft, from the residues of the reaction mixture are washed. After the specified time, stirring is stopped and the beads are again separated from the wash water with the remainder of the reaction mixture. The washing solvent is collected in a container where the previously separated suspension of the reaction mixture is located. The contents of this container are thoroughly mixed and left to stand for 1.5 hours, after which they are filtered. The precipitate is carefully squeezed on the filter, carefully removed and sent for cleaning by recrystallization. The yield of solid product was 92% of theoretical value. The precipitate is gently squeezed, removed from the filter and sent for cleaning by recrystallization.

The obtained filtrate is weighed, the content of the salt product, acetic acid and a stimulating additive, as well as the products of its conversion, is determined in it and returned to the loading of the repeated process. The amount of product returned with it was 4.2%.

Example 2-9

Reactor, initial reagents, solvent of the liquid phase, amount of stimulating additive, loading mass, sequence of operations when loading the reaction mixture, carrying out the process, its completion, separating the reaction mixture from beads, washing the beads and internal elements of the reactor from the residues of the reaction mixture, isolation from the last solid product and return of the filtrate to the loading of the repeated process are similar to those described in example 1. It differs in the amount of loading of copper oxide (II), the molar ratio of copper oxide (II) and acetic to Slots in the initial loading, and loading the weight ratio of the glass beads, the nature of the catalytic additive and an upper limit of the working temperature range. These differences and other characteristics are summarized in table 2 (PC - reaction mixture).

table 2

Download and process specifications Example 2 3 four 5 6 7 8 9 Dosage of copper oxide (II), mol / kg 1.8 2.5 3.0 3.3 2.0 2.0 2.0 2.0 The molar ratio of CuO to CH ₃ COOH in the initial load 1: 2.1 1: 1.7 1: 1.9 1: 1.7 1: 2.0 1: 2.0 1: 2.0 1: 2.0 The nature of the stimulant supplement iodine iodine iodine iodine potassium iodide potassium bromide barium chloride thiourea The mass ratio of glass beads and the rest of the load 1.5: 1 1.25: 1 1.25: 1 1.25: 1 1.3: 1 1.4: 1 1: 1 1.25: 1 PC temperature, ° C: initial twenty 21 22 22 21 twenty twenty twenty maximum 39 42 44 45 41 42 41 43 Time to reach product yield,% of theoretical; min 25 130 70 fifty 40 one hundred 80 40 85 fifty 225 130 110 95 180 155 80 165 75 300 200 170 155 280 240 130 260 95 and more () (98) 365 (97) 280 (97) 225 (98) 210 (97) 390 (97) 330 (98) 200 (97) 350 Duration of runoff of PC residues from the blade and shaft of the mixer, min 3 four 5 5 four four 3 5 The mass of introduced distilled water for washing the beads and reactor elements from residues PC, g thirty 40 40 45 35 35 35 35 Duration of washing beads and reactor elements from PC residues, min 10 12 13 13 9 8 10 10 Exposure to a mixture of a suspension of PC and wash water before filtering, hour 1,0 1,5 2.0 2.5 1,5 1,5 1,5 1,5 The yield of separated solid product in% of theoretical 90 92 93 93 91 91 91 90 Return of product with filtrate to the loading of the repeated process,% of the received 5.1 4.3 3.9 3,7 4.8 4.6 4.8 4,5

The positive effect of the proposed solution is:

1. In the proposed process, a high percentage of the mass transfer of the starting reagents to the mass of the target product is achieved. By-products are the average copper (II) salt and water as a result of further interaction of the product with excess acetic acid. But this process under the conditions under consideration can be significantly slowed down, which determines their small yield. In addition, the product-water is not an impurity and pollution.

2. In the proposed solution, the bulk of the product accumulates in the form of a suspended solid phase and is separated by simple filtration.

3. Mixing a suspension of the reaction mixture with washing water leads to a decrease in the solubility of the product by about half due to a decrease in the concentration of residual acetic acid, which favors the transition to the solid phase of additional quantities of the product.

4. The process is carried out at low temperatures and does not require the use of boiler monitoring equipment.

5. As reagents, it is possible to use copper oxide of natural origin and relatively dilute acetic acid.

6. The process is not complicated by the processing of the liquid phases of the final reaction mixture and the washing solvent.

Claims (2)

1. The method of producing basic copper (II) acetate by direct interaction of metal oxide with acid in a bead mill in the presence of a stimulating additive, characterized in that the process is carried out in the presence of a liquid phase, the solvent of which is distilled water, copper oxide is charged in an amount of 1.8 -3.3 mol / kg in a molar ratio with acetic acid (1: 1.7) ÷ (1: 2.1), the stimulating additive is dosed in an amount of 0.05 mol / kg, loading is carried out in the following sequence: glass beads, acetic acid solvent the stimulating additive and copper (II) oxide in the mass ratio of glass beads and the rest of the load (1: 1) ÷ (1.5: 1), then they include mechanical stirring and the process is carried out with continuous cooling in the temperature range of 20-45 ° С until the charged copper (II) oxide is almost completely consumed in the salt, after which the stirring and cooling are stopped, the suspension of the reaction mixture is separated from the glass beads, this suspension is mixed with wash water with the remains of the reaction mixture, left for 1-2.5 hours, filtered, precipitate product scrubber of drained and directed to the purification by recrystallization, and the filtrate is recycled to the re-loading process. 2. The method according to claim 1, characterized in that molecular iodine, iodide or potassium bromide, barium chloride or thiourea are used as a stimulating additive.