The method of producing benzaldehyde

 

(57) Abstract:

Use: in organic synthesis. The inventive product-benzaldehyde. Reagent 1 - toluene. The reagent 2 - oxygen of the air. Reaction conditions: catalyst consists of an active part of Vanadate silver composition: AgxV2O5+ where 0,5x0,9; d - value within the homogeneity region of the connection for oxygen and its maximum value is equal to 0.3, and media - carbide or nitride, or silicon carbonitride, the composition of the initial mixture, vol.%: pairs of toluene 5 - 29; oxygen 14,5 - 20, the nitrogen - rest. table 1.

The invention relates to the field of oxidation of aromatic compounds, in particular to a method for the catalytic gas-phase oxidation of toluene and benzaldehyde.

Known methods for producing benzaldehyde vapor-phase oxidation of toluene in the presence of a catalyst based on an oxygen vanadium bronzes composition Ag1,2-xCuxV3O8where 0X0,24 in the form of granules of 0.5-1.0 mm, and catalysts based on compounds of silver, vanadium, cerium, composition Ag1,2V3CeyO8+xwhere 0,03y0,18 with a particle size of 100-300 meters

The disadvantages of these methods of obtaining benzaldehyde is the instability of the process, the washed organic compounds a sharp drop in the selectivity of the process by increasing the size of the granules of the catalyst over 1 mm. in Addition, the catalysts used in these ways, do not contain inert carrier, which increases their cost due to the high content of precious metals (silver). All this makes wide use in industry data ways to get benzaldehyde.

Known vapor-phase method oxidation of toluene in benzaldehyde and benzoic acid in the presence of a catalyst containing vanadates silver or iron or these vanadates and Vanadate cerium atomic ratio of Ag:V 1:1; Fe:V 1:3; Ag: Fe: V 2: 1:5; Ag:Ce:V 2:1:5; Ag:Ce:Fe:V 2:1:1:8, deposited on a substrate of silicon dioxide or Al2O3[2]

The disadvantage of this method is the need to add in the reaction gas mixture (toluene + oxygen or ozone + nitrogen) water vapor, which complicates the process. Furthermore, the method is not efficient and has a low selectivity, in particular, benzaldehyde (table).

The closest technical solution to the present invention is a method of producing benzaldehyde gas-phase oxidation of toluene with oxygen or ozone with the addition of water vapor in the presence of catalysis is the Disadvantage of this method is the implementation process in the presence of large quantities of water vapor, what is associated with high energy consumption for evaporation of water in the preparation of the original provasoli (toluene, oxygen, nitrogen, water) and the transmission of these large quantities of vapors through the catalyst.

The complexity of the process of "capture" of the reaction products due to the big number by adding water vapor (requires powerful capacitors), the complexity of the allocation of benzaldehyde from the condensed reaction products, as they contain large amounts of water (large loss of benzaldehyde with water in their division), the presence of a large number of wastewater due to the high content of them in the original reaction mixture.

The technical result of the invention process in the absence of water vapor, which leads to simplification of the process, namely to reduce energy consumption, reduce the volume of wastewater, simplifying the process of "capture" of the reaction products, simplifying the selection of benzaldehyde from the condensed reaction products.

This result is achieved in the method of producing benzaldehyde vapor-phase oxidation of toluene with oxygen in the presence of a catalyst consisting of an active part on the basis of an oxide of vanadium compounds and silver, and n is a sconce composition AgxV2O5+ where 0,5x0,9, and as the carrier of the carbide or nitride or silicon carbonitride and the process is carried out at the following composition of the initial reaction mixture, about.

Pairs of toluene 5 29

Oxygen 14,5 20

Nitrogen Else.

The reactor is heated to the process temperature of 350 450oC., Preferably 380 to 420oC. and the load on the catalyst is equal to 615 - 2767 g in one liter of catalyst per hour /g/DS./ Then the vapor condenses and teaches a liquid reaction product containing as the main components of unreacted toluene, benzaldehyde and benzoic acid, the content of which is determined by gas-liquid chromatography and potentiometric titration.

Example 1. Take 2 ml of the catalyst containing 39 wt. Ag0,8V2O5+ d and 61% of the medium silicon carbide and 2 ml of quartz. Through this catalyst pass the mixture of vapors of toluene, oxygen, and nitrogen composition, about. toluene 6, oxygen 20, nitrogen 74 with a bulk velocity 10053 l/l hours At the reaction temperature of 420oC the conversion of toluene to benzaldehyde is 7.7% benzoic acid 2,2 and the products of complete combustion of 1.5% of the performance of the catalyst for benzaldehyde 205 g/l h and selectivity for benzaldehyde and b is a carrier of silicon nitride, and 2 ml of quartz. Through this catalyst is passed, the reaction mixture composition, about. toluene 5, oxygen 20, nitrogen 75 with a bulk velocity 10500 l/l hours At the reaction temperature of 420oC the conversion of toluene to benzaldehyde is equal to 7.9% in benzoic acid 2% and in the products of complete combustion of 1.8% Performance catalyst for benzaldehyde 250 g/L. H. and selectivity for benzaldehyde 67% and benzaldehyde and benzoic acid 85%

Example 3. The process is performed on the catalyst, as in example 2, the flowing gas mixture composition, the volume. toluene 10,4, oxygen 18,8, nitrogen 70,8 with a bulk velocity 3350 l/l hours At the reaction temperature of 420oC the conversion of toluene to benzaldehyde is equal to 10.5% and benzoic acid 3.9% and the products of complete combustion of 4.6% of the performance of the catalyst according to the benzaldehyde - 175 g/l h and selectivity for benzaldehyde 55% and benzaldehyde and benzoic acid 76%

Example 4. The process spends on the catalyst, as in example 2, the flowing gas mixture composition, about. toluene 8,7, oxygen 19,1, nitrogen 72,2 with a bulk velocity 3442 l/l hours At the reaction temperature of 380oC the conversion of toluene to benzaldehyde is equal to 6.2% in benzoic acid (2.8%) and in the products of complete combustion of 1.3% Performance catalyst for benzaldehyde 87 g/l h and selection the Torah, as in example 2, the flowing gas mixture composition, about. toluene 18,1, oxygen 17,1, nitrogen 64,8 with a bulk velocity 3662 l/l hours At the temperature of 420oC the conversion of toluene to benzaldehyde equal to 6.6% in benzoic acid 2.6% and in the products of complete combustion of 1.8% Performance catalyst for benzaldehyde 208 g/l h and selectivity for benzaldehyde 60% and benzaldehyde and benzoic acid - 84%

Example 6. Take 2 ml of the catalyst containing 35 wt. Ag0,5V2O5+ d and 65 wt. media silicon carbonitride and 2 ml of quartz. Through this catalyst is passed, the reaction mixture composition, about. toluene 6,7, oxygen 19,6, nitrogen 73,7, with a bulk velocity 10020 g/L. h At the reaction temperature of 420oC the conversion of toluene to benzaldehyde is equal to 5.3% and benzoic acid 3,4% and the products of complete combustion of 1.9% Performance catalyst for benzaldehyde 168 g/l h and selectivity for benzaldehyde 50% and benzaldehyde and benzoic acid 82%

Example 7. Take 2 ml of the catalyst containing 33 wt. Agfor 0.9V2O5+ d and 67 wt. media silicon carbonitride and 2 ml of quartz. Through this catalyst is passed, the reaction mixture composition, about. toluene 7,1, oxygen 19,5, nitrogen 73,4 with a bulk velocity 9878 l/l hours At the temperature of reaka 2.7% of the performance of the catalyst for benzaldehyde 272 g/L. hours and selectivity for benzaldehyde 57% and benzaldehyde and benzoic acid 82%

Example 8. The process is performed on the catalyst, as in example 6, the flowing gas mixture composition, about. toluene 29, oxygen 14,5, nitrogen 56,5 with a bulk velocity 3180 l/l hours At the reaction temperature of 440oC the conversion of toluene to benzaldehyde 5.5% benzoic acid 1.5% and in the products of complete combustion of 2.4% of the Performance of the catalyst for benzaldehyde 255 g/l h and selectivity for benzaldehyde 58% and benzaldehyde and benzoic acid 74%

The use of the proposed method of producing benzaldehyde allows to carry out the process in the absence of water vapor, which greatly simplifies the process, because it reduces the energy consumption for its implementation, reduces the volume of wastewater, simplifying the process of "capture" of the reaction products, simplifying the selection of benzaldehyde from the condensed reaction products. A positive effect is achieved by the use of a new catalyst composition containing new in its nature and composition of the active substance (AgxV2O5+ d, and the media (SiC, Si3O4, SiC1-xNxcompared with the patent of the USSR N 223662.

The method of obtaining benzaldehyd-based oxide, vanadium compounds and silver, and media-based silicon compound, characterized in that the active part of the catalyst used Vanadate silver composition

AgxV2O5+,

where 0,5 x 0,9;

d - value within the homogeneity region of the connection for oxygen and its maximum value is equal to 0.3, and

and as the carrier of the carbide or nitride or silicon carbonitride and the process is carried out at the following composition of the initial reaction mixture, about.

Pairs of toluene 5 29

Oxygen 14,5 20,0

The Nitrogen Ostalnoe

 

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2 ex

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2 ex

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15 ex

FIELD: chemistry.

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EFFECT: invention enables selective synthesis of desired products with high purity.

10 cl, 15 ex

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EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

FIELD: chemistry.

SUBSTANCE: claimed invention relates to method for obtaining 4,4'-diformyldiphenylalkane, represented by means of the following formula (2), which is suitable as different industrial chemical initial substances and in production of initial substances for medications, agrochemicals, optic and electronic functional materials. Method includes formylation of diphenylalkane, represented by means of the following formula (1), with carbon monoxide in presence of fluorohydrogen and boron trifluoride, in which temperature of formylation reaction constitutes from -50 to 5°C, from 5 to 30 mol of fluorohydrogen are used per 1 mol of diphenylalkane and from 1.5 to 5 mol of boron trifluoride are used per 1 mol of diphenylalkane:

in which R represents alkanediyl group, containing from 1 to 6 carbon atoms, in which R represents alkanediyl group, containing from 1 to 6 carbon atoms.

EFFECT: claimed method makes it possible to obtain target products with high degree of purity and with high output.

6 cl, 1 tbl, 8 ex

FIELD: chemistry.

SUBSTANCE: method is to interact α,α,α',α'-tetrabrom-p-xylene with dimethyl acetal of benzaldehyde in the presence of the catalytic amount of zinc chloride at the temperature of 80°C, followed by isolation of the desired product by extraction from the reaction mixture with hot isooctane.

EFFECT: producing the desired product with high yield.

2 ex

FIELD: chemistry.

SUBSTANCE: method is to interact α,α,α',α'-tetrabrom-p-xylene with dimethyl acetal of benzaldehyde in the presence of a catalytic amount of zinc chloride at the temperature of 50°C, followed by isolation of the desired product by extraction from the reaction mixture with hot isooctane.

EFFECT: producing the desired product with high yield.

3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a novel aromatic aldehyde represented by the formula

having a branched alkyl group containing from 10 to 14 carbon atoms and to the method for its production, to an epoxy resin curing composition comprising a polyamine compound and the claimed aromatic aldehyde, to the compositions based on epoxy resin for coating, of civil engineering and construction, containing the claimed curing composition, to the cured coating film and to the cured material. In formula (II), each of the groups R1 and R2 independently represents an alkyl group having 1 to 12 carbon atoms, and the total number of carbon atoms in the groups R1 and R2 is from 9 to 13.

EFFECT: improving the properties of aldehyde.

9 cl, 12 dwg, 2 tbl, 15 ex

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