Method of obtaining (meth)acrylic acid or (meth)acrolein

FIELD: chemistry.

SUBSTANCE: invention relates to improved method of obtaining (meth)acrylic acid or (meth)acrolein, which includes process of catalytic gas-phase oxidation for obtaining (met)acrylic acid or (meth)acrolein by supplying propylene, propane or isobutylene and gas, containing molecular oxygen, into reactor, filled with catalyst, which contains composition of metal oxides, including Mo, where gas, containing molecular oxygen, is continuously supplied from outside on catalyst both during installation operation, and during stoppage of catalytic gas-phase oxidation process.

EFFECT: obtaining gaseous reaction product, which includes (meth)acrylic acid or (meth)acrolein, in which reduction of catalyst activity and selectivity of target product formation do not occur when installation operation is restarted after stoppage of catalytic gas-phase oxidation process.

2 cl, 2 tbl, 2 ex

 

The technical field

The present invention relates to a method for producing (meth)acrylic acid or (meth)acrolein with good selectivity and high yield, in which propylene, propane or isobutylene is subjected to catalytic gas-phase oxidation of oxygen-containing gas.

The level of technology

As a method of obtaining a (meth)acrylic acid or (meth)acrolein has a way of propylene, propane, isobutylene is subjected to catalytic gas-phase oxidation of oxygen-containing gas in the presence of a catalyst to obtain (meth)acrolein and optionally (meth)acrolein is subjected to catalytic gas-phase oxidation with obtaining a gaseous reaction product comprising (meth)acrylic acid.

Here, (meth)acrolein means "acrolein or methacrolein" and (meth)acrylic acid means acrylic acid or methacrylic acid".

In the above-mentioned method, the catalyst for industrial production of (meth)acrylic acid or (meth)acrolein is a composition of metal oxides and catalytic gas-phase oxidation constantly, feeding raw material and oxygen-containing gas such as air, in the presence of a catalyst at all times during normal operation of the installation.

When propylene, propane, isobutylene and (meth)crole is h, which are raw materials or intermediate products obtain (meth)acrylic acid or (meth)acrolein, mixed with oxygen in a predetermined ratio, the resulting explosive composition, which can cause an explosion due to exposure to an ignition source such as a substance with a high temperature or electrical sparks. Therefore, in order to protect the production system from such explosion safely and automatically stop the operation of industrial installations, install automatic device for emergency stop (locking system), which produces flammable gases in the device from the system supply inflammable substances and blowing through the production installation of inert gases such as nitrogen, water vapor or so, when there is explosive composition.

When the unit re-start after such emergency off or after a shutdown for periodic testing are cases, when the reaction activity of the catalyst and the selectivity of the formation of the desired product are reduced.

In the patent JP-A-2002-53519 describes a secure way to run the reactor for catalytic gas-phase oxidation. However, given the description of the decision problem that the reaction activity of the catalyst and the selective behaviour is the General education of the desired product is reduced after the re-start of the installation.

Description of the invention

Therefore, the object of the invention is to develop a method of obtaining a (meth)acrylic acid or (meth)acrolein, including the implementation stage catalytic gas-phase oxidation feed of propylene, propane or isobutylene containing molecular oxygen gas in the reactor filled with the catalyst, and the gaseous reaction product containing (meth)acrylic acid or (meth)acrolein, in which the reaction catalyst activity and selectivity of the formation of the desired product does not fall when re-starting the operation after emergency stop for safety or after stopping for periodic control.

Based on the results of studies conducted to achieve a solution to the above task, the authors found that the reaction activity of the catalyst and the selectivity of the formation of the desired product decreases when the gas containing molecular oxygen (hereinafter referred to simply as "oxygen"), in the reactor filled with catalyst, stop at the stop time of the catalytic gas-phase oxidation and only served continuously water vapor and a gas containing no oxygen, such as nitrogen, and found that the deterioration of the catalyst activity can be predator the networks of gas supply, containing oxygen in the reactor during shutdown. Thus, the reach of the task of the invention.

That is, the present invention provides a method of obtaining a (meth)acrylic acid or (meth)acrolein, characterized by the following features.

1. A method of obtaining a (meth)acrylic acid or (meth)acrolein, which includes a process for the catalytic gas-phase oxidation to produce (meth)acrolein or (meth)acrylic acid feed of propylene, propane or isobutylene and a gas containing molecular oxygen in a reactor filled with a catalyst, whereby during idle time in the reactor filled with catalyst, serves a gas containing molecular oxygen.

2. The method according to the above option 1, in which the gas containing molecular oxygen, is fed into the reactor using the device safe for use during a shutdown process for the catalytic gas-phase oxidation.

The catalyst used in the catalytic gas-phase oxidation in the method of receiving according to the invention, is a composition of metal oxides containing many metals including Mo, etc. and even if molecular oxygen contained in the catalyst used for the oxidation of propylene, etc. and during normal operation of the plant, saying the molecular oxygen in the gas, reacting with propylene, etc. and serves on the catalyst, the oxidation state of the catalyst is maintained. In other words, accumulates on the catalyst regenerating substance, such as, in particular, heavy by-product. If oxygen is not available continuously, when the temperature of the catalyst supported in the conditions when the process for the catalytic gas-phase oxidation stops, such regenerating matter consumes oxygen catalyst itself is oxidized, restoring catalyst. Therefore, the oxidation state of the catalyst is changed, which leads to deterioration of the efficiency of the catalyst. I believe that according to the method of the invention, since, even during idle time, molecular oxygen is supplied from the outside to the catalyst in the reactor during operation, the oxidation state of the catalyst is maintained under conditions of high temperature and catalyst efficiency does not deteriorate.

The best way of carrying out the invention

Hereinafter the invention is described in detail.

In the method of receiving according to the invention, the mixed gas containing propylene, isobutylene, etc. and the inert gas are mixed and the gas containing molecular oxygen (hereafter to be referred to as "oxygen") is served in a reactor filled with catalyst, and receive (meth)acrylic sour is at or (meth)acrolein catalytic gas-phase oxidation.

The following systems can be listed as relevant to the way the response.

(System response)

Single-loop system, recycling the unreacted propylene and the recirculation system of flammable waste gases, described below, are suitable representative examples of reaction systems in the industrial method of producing acrolein and acrylic acid. However, in the present invention the reaction system includes three such systems and are not limited to these systems.

(1) Single-circuit system

The system is intended for a method of mixing and feeding of propylene, air and steam in the reaction upstream and transformation mixture mainly acrolein and acrylic acid and the feed mixture in the reaction below flow without separation of products from the outgoing gas. At the same time, the method of supplying air and steam required for the reaction downstream, in response downstream, in addition to leaving gas upstream, is common.

(2) recycling unreacted propylene

In the system of gaseous reaction products containing acrylic acid which is obtained by reaction downstream, injected into the device-collector for acrylic acid, and acrylic acid is collected as an aqueous solution. Part of the exhaust gas containing unreacted propylene from the device-collector serves to response upstream or reactions downstream, when the recycle portion of the unreacted propylene.

(3) the recirculation System exhaust gaseous products of combustion

In the system of gaseous reaction products containing acrylic acid, which is obtained in the reaction downstream, injected into the device-collector for acrylic acid, and acrylic acid is collected in the form of aqueous solution. The entire quantity of exhaust gases from the device-collector burn and oxidize, and unreacted propylene, etc. contained in them, transform, mainly carbon dioxide and water, and the part thus obtained waste gaseous products of combustion is added to the reaction upstream or respond in a lower stream.

Usually use a tubular reactor, when it is necessary to increase the productivity of the reactor preservation is largely catalyst efficiency is the accurate control of the reaction temperature of the catalyst and protection of the catalyst, even when the heat of reaction is much higher than in the reaction of oxidation.

In recent years, production of acrylic acid from propylene and methacrylic acid from isobutylene (these acids are called in the future "(meth)acrylic acid") has significantly increased due to increased demand, in this regard, the number of plants built around the world, and the scale of production on installation increased to one hundred thousand tons or more annually. In accordance with scale factory production, there is a need to increase the amount of products in the oxidation reactor. As a result, the load on the reactor for catalytic gas-phase oxidation of propane, propylene or isobutylene increases. In this regard, the required tubular reactor high performance.

In the invention using a tubular reactor, which comprises in the longitudinal direction of the pipe reactor cylindrical reactor vessel having an opening for flow of raw materials and an aperture for discharge of the product; many of annular conduits for the introduction of fluid into the cylindrical reactor vessel for removal of coolant, which are located on the outer circumference of the cylindrical reactor; a device that provides circulation to connect multiple circular pipes with each other; many reaction tubes, which are fixed with many bars for pipe reactor containing a catalyst; and a set of guide walls for changing the direction of flow of the coolant introduced into the reactor vessel, where to oxidize substances are preferably used in isout catalytic gas-phase oxidation gas, containing molecular oxygen, and, for example, at least one of the catalysts of the oxidation catalyst based on the Mo-Bi catalyst based on Mo-V fill the above reaction tubes.

The present invention relates to catalytic gas-phase oxidation method for obtaining at least one of the products, (meth)acrolein and (meth)acrylic acid, a catalytic gas-phase oxidation gas containing molecular oxygen, the use of propylene, propane, isobutylene or (meth)acrolein or mixtures thereof as a substance to be oxidized. (Meth)acrolein or (meth)acrylic acid or both products can be obtained from propylene, propane or isobutylene. In addition, (meth)acrylic acid can be obtained from (meth)acrolein.

In the invention "process gas" means gas that participate in the catalytic gas-phase oxidation reaction, comprising oxidizable substance and the gas containing molecular oxygen as gaseous raw materials and the resulting product. Additionally, the "raw material" means a substance to be oxidized.

(The composition of the gaseous raw material)

In the tubular reactor used for the catalytic gas-phase oxidation, as gaseous raw materials mainly serves gaseous mixture of at least one substance that Dol is but to be oxidized, propylene, propane, isobutylene and (meth)acrolein, gas containing molecular oxygen and an inert gas such as water vapor.

In the invention, the concentration of oxidizable substances in the gaseous raw material is in the range from 6 to 10 mol.%, and oxygen is more than 1.5 to 2.5 times the number of moles of a substance to be oxidized, and the inert gas is present in the amount of 0.8 to 5 times by mol the amount of the substance to be oxidized. Enter the gaseous raw material is distributed inside the appropriate reaction tubes, passes through the respective pipes and reacts in the presence of the oxidation catalyst, filler pipe.

(Tubular reactor)

The tubular reactor is widely used when obtaining the (meth)acrylic acid or (meth)acrolein carried out using a gas containing molecular oxygen, in the presence of a composition of oxides as catalyst for the reaction of catalytic gas-phase oxidation.

The tubular reactor used in the invention is mainly used for industrial purposes. No special restrictions. The tubular reactor, which is preferably used, as described in the patent application of Japan No. 2003-416718.

The gas containing oxygen, which is used in the present invention is, for example, air and the exhaust gas, containing oxygen, which is formed in the other industrial installations, preferably air.

The above-described inert gas is water vapor, nitrogen, or carbon dioxide budget for industrial purposes. More economical to use recirculating the mixed gas, which is collected and separated from the gaseous reaction products obtained by catalytic gas-phase oxidation.

(Catalyst)

In the catalytic gas-phase oxidation reaction to obtain (meth)acrylic acid or (meth)acrolein apply two types of catalysts, one of which is used in the reaction for the conversion of olefins to unsaturated aldehyde or unsaturated acid upstream, and the other of which is used for reaction conversion of unsaturated aldehyde downstream. The invention is favorable catalyst adapted to any of the reactions.

In the above-mentioned catalytic gas-phase oxidation reaction, the catalyst having the General formula (I)may be listed as the composite oxide catalyst on the basis of the Mo-Bi used for the reaction upstream (reaction conversion of olefins to unsaturated aldehyde or unsaturated acid) to obtain, mainly acrolein.

MoaWbBicFedAeBfCgDhEiOx(I)

p> In the abovementioned formula (I) And represents at least one type of element selected from Nickel and cobalt, A represents at least one type of element selected from sodium, potassium, rubidium, cesium and thallium, represents at least one type of element selected from alkaline earth metal, D is at least one type of element selected from phosphorus, tellurium, antimony, tin, cerium, lead, niobium, manganese, arsenic, boron and zinc, E represents at least one the type of element selected from silicon, aluminum, titanium and zirconium, and O represents oxygen. Also a, b, c, d, e, f, g, h, i, and x respectively denote the atomic relations of Mo, W, Bi, Fe, A, B, C, D, E, and O in the case when a=12, 0 ≤ b ≤ 10, 0 < c ≤ 10 (preferably of 0.1 ≤ C ≤ 10), 0 < d ≤ 10 (preferably of 0.1 ≤ d ≤ 10), 2 ≤ e ≤ 15, 0 < f ≤ 10 (preferably of 0.001 ≤ f ≤ 10), 0 ≤ g ≤ 10, 0 ≤ h ≤ 4 and 0 ≤ i ≤ 30, and x is a variable determined by the oxidation state of the elements.

A catalyst having the General formula (II) can be listed as the composite oxide catalyst based on Mo-V, which is used in the reaction downstream (reaction conversion of unsaturated aldehyde to unsaturated acid) for obtaining acrylic acid by oxidation of acrolein the above catalytic reaction of gas-phase oxidation.

aVbWcCudXeYfOg(II)

In the General formula (II), X represents at least one kind of element selected from Mg, Ca, Sr and BA, Y represents at least one kind of element selected from Ti, Zr, Ce, Cr, Mn, Fe, Co, Ni, Zn, Nb, Sn, Sb, Pb and Bi, and O represents oxygen. Also a, b, c, d, e, f and g respectively denote the atomic relations of Mo, V, W, Cu, X, Y and O, and when a=12, 2 ≤ b ≤ 14, 0 ≤ c ≤ 12, 0 < d ≤ 6, 0 ≤ e ≤ 3, 0 ≤ f ≤ 3, and g is a variable determined by the oxidation state of the respective elements.

The above-mentioned catalyst produced according to the methods described, for example, in the patent JP-A-63-54942, JP-B-6-13096 and JP-B-6-38918.

The catalyst used in the invention may be a catalyst molded by the molding method, extrusion or molding method, compression of tablets, or may be a catalyst in which a composite oxide formed of the catalyst components deposited on the inactive carrier such as silicon carbide, aluminum oxide, zirconium oxide, titanium oxide, etc.

In addition, there are no specific limitations to the form of the catalyst used in the invention. The catalyst may be any of the forms of spheres, rods, cylinders, stars, rings or irregular shape.

(Diluent)

The above-mentioned catalyst can be used together with is mixed with an inactive substance as a diluent.

The inactive substance is stable in the above-mentioned reaction conditions. The substance has no special restrictions, if it is not specifically interacts with the raw material and the product. In more detail, it is preferable to apply the substance used as a catalyst carrier such as alumina, silicon carbide, silicon oxide, zirconium oxide, titanium oxide, etc.

The inactive form of matter has no specific restrictions as catalyst. The shape can be spherical, rod, cylindrical, star-shaped, ring-shaped, such small particles, like the grid or irregular shape. The size of the substance, determine, taking into account the diameter of the reaction tubes and pressure losses.

Application number inactive substance used as a diluent, can be adequately define the target catalytic activity of the catalyst.

(Regulation layer and the activity of the catalyst)

The activity of the catalytic layer in the reaction tube can be changed.

As a method of control for changing the activity of the catalyst in the reaction tubes can be listed a method of regulating the activity of the respective layers of catalyst in the case of the use of catalysts having different activities in the respective layers of the SC is alistore, carried out, for example, by regulating the composition of the catalysts or dilution of catalysts in which the catalyst pellet is mixed with granules inactive substances.

As a detailed example of the latter method can be described in such a way that the catalyst can be produced, for example, in the form of two layers, a layer of catalyst on the entrance part of the gaseous raw material into the reaction tubes that are manufactured in the form of a catalytic layer having a higher ratio of granules inactive substance, that is, the application of granules inactive compounds to the catalyst comprising from 0.3 to 0.7, to obtain a layer with low activity, and the catalytic layer on the outlet side of the reaction tubes that are manufactured as high-level layer of establishing relations with the low content of inactive substances, for example, from 0.5 to 0.8 or filling a catalyst without a solvent.

A number of catalytic layers formed in the direction of the axis of the tube of the tubular reactor, with no special restrictions. As work on the content of the catalyst is difficult and requires more effort, if you have multiple catalytic layers, the recommended number of layers of catalyst is 1-10. In addition, the length of the respective layers of catalyst install dequate value based on the type of catalyst, amount of catalyst and the reaction conditions. Therefore, the length can be set such that the result of the invention was maximum.

As described above, it is possible to carry out catalytic gas-phase oxidation in accordance with the invention with the use of a reactor with the catalyst and reaction tubes. Gaseous reaction products obtained by the method of catalytic gas-phase oxidation, include the required products, such as (meth)acrylic acid and (meth)acrolein, and gaseous reaction products are subjected to separation in order to obtain the desired products.

In the normal mode of the catalytic gas-phase oxidation gas containing oxygen for the oxidation reaction, for example air, is fed into the reactor using a device for supplying gas, such as a compressor. In other words, as the device for gas supply is stopped during shutdown for periodic monitoring or during shutdown in case of emergency, the flow in the reactor, propylene, propane, isobutylene and gas containing oxygen, which is the gaseous raw material to stop it.

In the invention, the reactor is connected to a device that can be used for an emergency stop so that even during a stop process catalyti the definition of gas-phase oxidation gas, containing oxygen, such as air flowed into the catalyst, when the gas containing oxygen is fed into the reactor.

A device for dispensing air, a reservoir for compressed gas and a compressor for supplying gas, combined with a reliable source of energy, you can list it as a device that can be used during shutdown.

Preferably, the amount of gas containing oxygen in the reactor during shutdown was 0.2-50 l(norm.) an hour on the tube reactor. In a reactor having 10000-30000 pipes, the amount of gas containing oxygen, was 5-500 m3(norm.) per hour per reactor and more preferably 100-300 m3(norm.) per hour per reactor. In addition, a gas containing oxygen, which is used at this time may be oxygen-containing gas, which is used for the catalytic gas-phase oxidation. However, it is preferable to apply the air.

In addition, gas containing oxygen is available until until re-run setup. In more detail, the gas supply will continue until such time as the oxygen-containing gas is fed into the reactor as a gaseous raw material.

The operation from normal operation to stop the operation from stop to re-start the installation can be adequately conduct depending on the performance of the device is. For example, in the case when the process is carried out to obtain acrylic acid or acrolein from propylene, as shown below.

(The pre-shutdown)

(During operation, the temperature in the reactor is 300°C. or more, the pressure is from atmospheric pressure up to twice atmospheric pressure or less).

(1) the Supply of propylene was stopped.

(2) the Supply of water vapor and inert gas stop (Temperature gradually decreases from 300°C or more, the pressure is usually from atmospheric pressure up to twice atmospheric pressure).

(3) reduce the Temperature of the supply air (the Temperature was lowered to 130°C or below. As the temperature of the air from the compressor to supply air high temperature can not be lower than 130°C., and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or below).

(4) the Compressor for the air supply is stopped and opened the facility in order to cause a further decrease of the temperature (i.e., from 130°C. to room temperature, and the pressure corresponds to the atmospheric pressure). At this time, the apparatus-side downstream (device, in which process the outgoing gaseous reaction products) can be stopped.

The gas containing oxygen can be fed into the reactor from above the stage (4), e.g. the measures using a device with a feeder to supply air (to measure the amount of air).

(Emergency shutdown)

(1) the Supply of propylene was stopped.

(2) Block the exit of the apparatus below the reactor on stream and discharged effluent from the reactor gas into the atmosphere.

(3) Continuously served water vapor and inert gas (the Temperature gradually decreases from 300°C or more, and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or less).

(4) Temperature, as expected, decreases (the Temperature gradually decreases from 300°C or lower, and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or less).

(5) If the indicators allow the start of the installation work, the following start installation start from operations (2).

(6) If the operation of the air compressor cannot be performed, predetermined amount of air (Temperature gradually decreases from 300°C or more, and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or below).

The gas containing oxygen can be fed into the reactor from above the stage (4), for example, with the use of devices for supply air, is supplied by a dispenser (which measures the amount of air). However, gas is not available in the case wisenut the Anna stage (5).

(Operation status stop working installation before re-start of the installation)

(1) the unit is on the side downstream of the reactor.

(2) the Inclusion of a compressor for air supply.

(3) the air Supply from the compressor to supply air to the reactor (Temperature rises from room temperature to air temperature (120°C or so), and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or below).

(4) the temperature Rise in the reactor using a furnace or electric heater (the Temperature is raised from 120°C or so until the temperature of the beginning of the operation, approximately 300°C., and the pressure is usually from atmospheric pressure up to twice atmospheric pressure or less).

(5) Establishment of conditions for the operation (Supply of materials (vapor and inert gas)that is different from the propylene under the conditions of the start of the installation. The temperature is set to approximately 300°C., the pressure is set from atmospheric pressure up to twice atmospheric pressure or less).

(6) the Beginning of the feed of propylene.

The gas containing oxygen into the reactor using a metered amount of air is stopped at the above stage (3).

(Example)

Here is a detailed description of the image is to be placed on the basis of example. However, the scope of the invention is not limited to the example.

(Example 1)

When carrying out the oxidation reaction of propylene was obtained a powder catalyst having a composition of Mo(12)Bi(5)Ni(3)Co(2)Fe(0,4)Na(0,2)B(0,4)K(0,1)Si(24)O(x). Figures in parentheses represent the atomic relations. Index (x) of oxygen is determined on the basis of the degree of oxidation of the metal. The catalyst powder was molded to obtain a solid catalyst, and the obtained solid catalyst used in the reaction.

When using a reaction tube made of stainless steel, length 3.5 m, an internal diameter of 24 mm, an external diameter of 28 mm, as a coolant to maintain the temperature of the reaction was used molten salt mixture of nitrates, the nitrate.

1,5 liters of the above-mentioned catalyst filled in the reaction tube and pull air in quantities of 50 l(norm.) in the hour of the reaction tube before installation. The catalyst was in the air. With supply air temperature in the reactor was increased from room temperature to 320°C. Then, when the regulation of the pressure at the inlet to the reactor so that it was 75 kPa (kilopascals) in units of gauge pressure, gaseous raw material was applied so that if the flow temperature of 325°C, the supply of propylene was 150 l(norm.) per hour, the flow of water n the RA was 150 l(norm.) per hour, the air supply was 1125 l(norm.) per hour and the flow of nitrogen was 75 l(norm.) per hour (Here l(norm.) indicates the volume at 0°C and at atmospheric pressure).

Formed in the reaction gas was analyzed by gas chromatography, the yield of products is shown in table 1.

Table 1
ProductsOutputs
Acrolein+Acrylic acid91,5%
Carbon monoxide1,5%
Carbon dioxide2,6%
Acetic acid1,4%
Propylene3,0%

(Comparative example 1)

Installation work was carried out, as shown below, with the use of a catalyst and apparatus for the reaction, which is regulated by the method same as in example 1.

Nitrogen was applied in the amount of 50 l(norm.) an hour on the tube reactor before starting the installation after completing the catalyst. It remained unchanged in one day. When I started to apply nitrogen, the reactor temperature was raised from room tempera is URS to 320°C. After that, when the regulation of the pressure at the inlet to the reactor so that it corresponded to 75 kPa (kilopascals) in units of gauge pressure, gaseous raw material was applied so that when the coolant temperature of 325°C, the supply of propylene was 150 l(norm.) per hour, steam was 150 l(norm.) per hour, the air supply was 1125 l(norm.) per hour, the flow of nitrogen was 75 l(norm.) per hour (here l(norm.) indicates the volume at 0°C and at atmospheric pressure).

Gaseous products were analyzed by gas chromatography, the yields of products are shown in Table 2.

Table 2
ProductsOutputs
Acrolein+Acrylic acid89,3%
Carbon monoxide1,7%
Carbon dioxide4,2%
Acetic acid1,3%
Propylene3,5%

By comparing Table 1 with Table 2, found that the case of example 1, in which the gas containing oxygen is fed into the reactor, Zap lenny catalyst, before you begin the installation (i.e., before feeding propylene), is the best on the reaction activity and selectivity of the formation of the desired product.

Although the invention has been described in detail and with reference to specific variations in its implementation, for specialists in this area it is obvious that various changes and modifications not beyond the nature and scope of the invention.

This application is based on patent application of Japan (Application No. 2004-135311), registered on 30 April 2004, the full contents of which are incorporated herein by reference.

(Industrial applicability)

In accordance with the method of the invention, the reaction activity of the catalyst and the selectivity of the formation of the desired product upon receipt (meth)acrolein or (meth)acrylic acid catalytic gas-phase oxidation of propylene, propane or isobutylene using gas containing oxygen, is stored even when the unit re-start after a shutdown.

1. A method of obtaining a (meth)acrylic acid or (meth)acrolein, which includes a process for the catalytic gas-phase oxidation to obtain (meth)acrylic acid or (meth)acrolein feed of propylene, propane or isobutylene and a gas containing molecular oxygen in a reactor filled katal is congestion, containing a composition of metal oxides, including Mo, where the gas containing molecular oxygen, continuously served outside on the catalyst during operation, and during a stop process for the catalytic gas-phase oxidation.

2. The method according to claim 1, wherein a gas containing molecular oxygen, is fed into the reactor with the use of devices that provide safety for use during a stop process for the catalytic gas-phase oxidation.



 

Same patents:

FIELD: chemistry.

SUBSTANCE: object of the present invention is to develop method for making catalyst to produce methacrylic acid by gaseous catalytic oxidation of metacrolein, isobutyl aldehyde or isobutyric acid. There is disclosed method for making catalyst to produce methacrylic acid by gaseous catalytic oxidation of metacrolein, isobutyl aldehyde or isobutyric acid, involving as follows: (a) the stage of mixing water and compounds, each containing any Mo, V, P, Cu, Cs or NH4, to prepare aqueous solution or dispersed compounds (further, both mentioned as a suspension); (b) the stage of drying suspension produced at the stage (a), to make dry suspension; (c) the stage of burning dry suspension produced at the stage (b), to make burnt substance; (d) the stage of filtrating mixed burnt substance produced at the stage (c) and water to separate aqueous solution and water-insoluble substance; and (e) the stage of drying water-insoluble substance produced at the stage (d) to make dry water-insoluble substance; and (f) the stage of coating the carrier with dry water-insoluble substance produced at the stage (e), with using a binding agent to make coated mould product, and (g) the stage of burning coated mould product produced at the stage (f) in inert gas atmosphere, in the air or with reducing agent added.

EFFECT: making catalyst with long life, high activity and selectivity.

8 cl, 9 tbl, 9 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid and complex (met)acrylic esters, involving the following stages: (A) reacting propane, propylene or isobutylene and/or (met)acrolein with molecular oxygen or with a gas, containing molecular oxygen through gas-phase catalytic oxidation, obtaining crude (met)acrylic acid; (B) purification of the obtained crude (met)acrylic acid, obtaining a (met)acrylic acid product; and (C) reacting raw (met)acrylic acid with alcohol, obtaining complex (met)acrylic esters, in the event that the installation used in any of the stages (B) and (C), taking place concurrently, stops. The obtained excess crude (met)acrylic acid is temporarily stored in a tank. After restoring operation of the stopped installation, the crude (met)acrylic acid, stored in the tank, is fed into the installation, used in stage (B), and/or into the installation used in stage (C). (Met)acrylic acid output of the installation used in stage (A) should be less than total consumption of (met)acrylic acid by installations used in stages (B) and (C).

EFFECT: the method allows for processing (met)acrylic acid, temporarily stored in a tank, when stage (B) or (C) stops, without considerable change in workload in stage (A).

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SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid or (met)acrolein using a multi-pipe reactor with a fixed bed. The reactor has several pipes, with at least one catalyst bed in the direction of the axis of the pipe. A heat carrier can regulate temperature outside the flow of the reaction pipe. In the reaction pipes, there is gas-phase catalytic oxidation of at least one type of oxidisable substance, propylene, propane, isobutylene and (met)acrolein by molecular oxygen or a gas, containing molecular oxygen. At the beginning of the process, the difference between the coolant temperature and the peak temperature of the catalyst is set in the interval 20-80°C, and during the process, peak temperature T(°C) of the catalyst in the direction of the axis of the pipe satisfies equation 1, given below: (equation 1), where L, T0, X and X0 stand for length of the reaction pipe, peak temperature of the catalyst in the direction of the axis of the pipe at the beginning of the process, the length up to the position which gives the peak temperature T at the input of the reaction pipe, and the length to the position which gives the peak temperature T0 at the input of the reaction pipe, respectively.

EFFECT: method allows for stable output of the target product, with high output for a long period of time, without reduction of catalyst activity.

3 dwg, 2 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid or (met)acrolein using a multi-pipe reactor with a fixed bed. The reactor has several pipes, with at least one catalyst bed in the direction of the axis of the pipe. A heat carrier can regulate temperature outside the flow of the reaction pipe. In the reaction pipes, there is gas-phase catalytic oxidation of at least one type of oxidisable substance, propylene, propane, isobutylene and (met)acrolein by molecular oxygen or a gas, containing molecular oxygen. At the beginning of the process, the difference between the coolant temperature and the peak temperature of the catalyst is set in the interval 20-80°C, and during the process, peak temperature T(°C) of the catalyst in the direction of the axis of the pipe satisfies equation 1, given below: (equation 1), where L, T0, X and X0 stand for length of the reaction pipe, peak temperature of the catalyst in the direction of the axis of the pipe at the beginning of the process, the length up to the position which gives the peak temperature T at the input of the reaction pipe, and the length to the position which gives the peak temperature T0 at the input of the reaction pipe, respectively.

EFFECT: method allows for stable output of the target product, with high output for a long period of time, without reduction of catalyst activity.

3 dwg, 2 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to perfection of the method of obtaining at least, one product of partial oxidation and/or ammoxidising of propylene, chosen from a group, comprising propylene oxide, acrolein, acrylic acid and acrylonitrile. The starting material is raw propane. a) At the first stage, raw propane, in the presence and/or absence of oxygen, is subjected to homogenous and/or heterogeneous catalysed dehydrogenation and/or oxydehydrogenation. Gas mixture 1, containing propane and propylene is obtained. b) If necessary, a certain quantity of the other components in gas mixture 1, obtained in the first stage, besides propane and propylene, such as hydrogen and carbon monoxide is separated and/or converted to other compounds, such as water and carbon dioxide. From gas mixture 1, gas mixture 1' is obtained, containing propane and propylene, as well as other compounds, besides oxygen, propane and propylene. c) At the third stage, gas mixture 1 and/or gas mixture 1' as a component, containing molecular oxygen, of gas mixture 2, is subjected to heterogeneous catalysed partial gas-phase oxidation and/or propylene, contained in gas mixture 1 and/or gas mixture 1', undergoes partial gas-phase ammoxidising. Content of butane-1 in gas mixture 2 is ≤1 vol.%. The method increases output of desired products and efficiency of the process.

EFFECT: increased output of desired products and efficiency of the process.

72 cl, 10 ex

FIELD: heating.

SUBSTANCE: invention concerns improved method of catalytic oxidation in vapour phase which supplies effective removing of reactionary heat, excludes hot spot formation, and supplies effective receipt of base product. Method of catalytic oxidation is disclosed in the vapour phase (a) of propylene, propane or isobutene by the instrumentality of molecular oxygen for receiving (meth)acrolein, and/or oxidation (b) of (meth)acrolein by molecular oxygen for receiving (meth)acryl acid, by the instrumentality of multiple-tubular reactor, contained: cylindrical reactor vessel, outfitted by initial material supply inlet hole and discharge hole for product, variety of reactor coolant pipes, located around the cylindrical reactor vessel and used for insertion the heat carrier into cylindrical reactor vessel or for removing the heat carrier from it, circulator for connection of variety loop pipeline to each other, variety of reaction tube, mounted by the instrumentality of tube reactor lattices, with catalyst. Also multiple-tubular reactor contains: variety of partitions, located lengthways of reaction tubes and used for changing heat carrier direction, inserted into reactor vessel. According to this heat carrier coolant flow is analysed and there are defined zones in reactor which have heat-transfer coefficient of heat carrier less than 1000 W/(m2·K); also reaction of catalytic oxidation is averted in the vapour phase in mentioned zones of reactor and reaction of catalytic oxidation is implemented in the vapour phase in reactor.

EFFECT: receiving of improved method catalytic oxidation in vapour phase which supplies effective removing of reactionary heat, excludes hot spot formation, and supplies effective receipt of base product.

3 cl, 6 dwg, 2 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to improved process to produce acrylic acid via heterogeneously catalyzed gas-phase partial oxidation of propane wherein starting reactive gas mixture containing propane, molecular oxygen, and at least one gas diluent is passed at elevated temperature over a multimetal oxide bulk depicted by total stoichiometry as Mo1VbM1сM2вOn (I), in which M1 = Te and/or Sb and M2 is at least one element from group comprising Nb, Ta, W, Ti, Al, Zr, Cr, Mn, Ga, Fe, Ru, Co, Rh, Ni, Pd, Pt, La, Bi, B, Ce, Zn, Si, and In; b = 0.01 to 1, c = >0 to 1, d = >0 to 1, and n = number, which is determined by valence and number of non-oxygen elements in (I). Propane is partially oxidized to produce acrylic acid in a process wherein composition of starting reaction mixture is at least two times varied in the course of process such that molar percentage of gas diluent (water steam) in starting reaction gas mixture decreases relative to molar percentage of propane contained in starting gas mixture.

EFFECT: reduced amount of water steam in gas mixture without loss in selectivity and activity of catalyst regarding target product.

5 cl, 1 dwg, 10 ex

FIELD: improved method for production of (meth)acrolein and (meth)acrylic acid.

SUBSTANCE: claimed method includes feeding of raw gas mixture through pipeline from raw material mixer into oxidation reactor and catalytic oxidation of raw mixture in vapor phase to produce (meth)acrolein or (meth)acrylic acid. Said pipeline is heated and/or maintained in heated state and temperature of gas mixture fed into oxidation reactor is by 5-250C higher then condensation temperature of raw gas mixture.

EFFECT: stable and effective method for production of (meth)acrolein and (meth)acrylic acid without alteration of raw mixture composition, abrupt temperature elevation and reducing of catalyst activity and durability.

5 cl, 1 dwg, 2 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for preparing acrylic acid and selective oxidation of propylene to acrolein. Method involves carrying out reaction of propylene with oxygen in the first zone reaction with the first catalyst corresponding to the following formula: AaBbCcCadFeeBifMo12Ox wherein A means Li, Na, K, Rb and Cs and their mixtures also; B means Mg, Sr, Mn, Ni, Co and Zn and their mixtures also; C means Ce, Cr, Al, Sb, P, Ge, Sn, Cu, V and W and their mixtures also wherein a = 0.01-1.0; b and e = 1.0-10; c = 0-5.0 but preferably 0.05-5.0; d and f = 0.05-5.0; x represents a number determined by valence of other presenting elements. Reaction is carried out at enhanced temperature providing preparing acrylic acid and acrolein and the following addition of acrolein from the first reaction zone to the second reaction zone containing the second catalyst used for conversion of acrolein to acrylic acid. Method provides high conversion of propylene to acrylic acid and acrolein.

EFFECT: improved preparing method.

7 cl, 1 tbl, 5 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for preparing acrylic acid and selective oxidation of propylene to acrolein. Method involves carrying out reaction of propylene with oxygen in the first zone reaction with the first catalyst corresponding to the following formula: AaBbCcCadFeeBifMo12Ox wherein A means Li, Na, K, Rb and Cs and their mixtures also; B means Mg, Sr, Mn, Ni, Co and Zn and their mixtures also; C means Ce, Cr, Al, Sb, P, Ge, Sn, Cu, V and W and their mixtures also wherein a = 0.01-1.0; b and e = 1.0-10; c = 0-5.0 but preferably 0.05-5.0; d and f = 0.05-5.0; x represents a number determined by valence of other presenting elements. Reaction is carried out at enhanced temperature providing preparing acrylic acid and acrolein and the following addition of acrolein from the first reaction zone to the second reaction zone containing the second catalyst used for conversion of acrolein to acrylic acid. Method provides high conversion of propylene to acrylic acid and acrolein.

EFFECT: improved preparing method.

7 cl, 1 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: catalytic composition for ethane and/or ethylene oxidation to acetic acid contains the following elements combined with oxygen: molybdenum, vanadium, niobium and gold without palladium according to the empirical formula: MoaWbAucVdNbeYf (I), where Y stands for one or morel elements chosen from group, including Cr, Mn, Ta, Ti, B, Al, Ga, In, Pt, Zn, Cd, Bi, Ce, Co, Rh, Ir, Cu, Ag, Fe, Ru, Os, K, Rb, Cs, Mg, Ca, Sr, Ba, Zr, Hf, Ni, P, Pb, Sb, Si, Sn, Tl, U, Re, Te and La; a, b, c, d, e and f stand for such gram-atomic element ratios whereat 0.01<a≤1; 0≤b<1 and a+b=1; 0.0005<c<0.001; 0.45≤d≤0.7; 0.15≤e≤0.20; and 0.6≤d+e≤0.9, and 0≤f≤0.02. Besides, there is disclosed method of selective production of acetic acid from mixed gases containing ethane and/or ethylene, involving contacting mixed gases and gas containing molecular oxygen at raised temperature with aforesaid catalytic composition added.

EFFECT: improved selectivity of acetic acid formation.

9 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid and complex (met)acrylic esters, involving the following stages: (A) reacting propane, propylene or isobutylene and/or (met)acrolein with molecular oxygen or with a gas, containing molecular oxygen through gas-phase catalytic oxidation, obtaining crude (met)acrylic acid; (B) purification of the obtained crude (met)acrylic acid, obtaining a (met)acrylic acid product; and (C) reacting raw (met)acrylic acid with alcohol, obtaining complex (met)acrylic esters, in the event that the installation used in any of the stages (B) and (C), taking place concurrently, stops. The obtained excess crude (met)acrylic acid is temporarily stored in a tank. After restoring operation of the stopped installation, the crude (met)acrylic acid, stored in the tank, is fed into the installation, used in stage (B), and/or into the installation used in stage (C). (Met)acrylic acid output of the installation used in stage (A) should be less than total consumption of (met)acrylic acid by installations used in stages (B) and (C).

EFFECT: the method allows for processing (met)acrylic acid, temporarily stored in a tank, when stage (B) or (C) stops, without considerable change in workload in stage (A).

2 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid or (met)acrolein using a multi-pipe reactor with a fixed bed. The reactor has several pipes, with at least one catalyst bed in the direction of the axis of the pipe. A heat carrier can regulate temperature outside the flow of the reaction pipe. In the reaction pipes, there is gas-phase catalytic oxidation of at least one type of oxidisable substance, propylene, propane, isobutylene and (met)acrolein by molecular oxygen or a gas, containing molecular oxygen. At the beginning of the process, the difference between the coolant temperature and the peak temperature of the catalyst is set in the interval 20-80°C, and during the process, peak temperature T(°C) of the catalyst in the direction of the axis of the pipe satisfies equation 1, given below: (equation 1), where L, T0, X and X0 stand for length of the reaction pipe, peak temperature of the catalyst in the direction of the axis of the pipe at the beginning of the process, the length up to the position which gives the peak temperature T at the input of the reaction pipe, and the length to the position which gives the peak temperature T0 at the input of the reaction pipe, respectively.

EFFECT: method allows for stable output of the target product, with high output for a long period of time, without reduction of catalyst activity.

3 dwg, 2 ex

FIELD: chemistry.

SUBSTANCE: present invention pertains to perfection of the method of obtaining at least, one product of partial oxidation and/or ammoxidising of propylene, chosen from a group, comprising propylene oxide, acrolein, acrylic acid and acrylonitrile. The starting material is raw propane. a) At the first stage, raw propane, in the presence and/or absence of oxygen, is subjected to homogenous and/or heterogeneous catalysed dehydrogenation and/or oxydehydrogenation. Gas mixture 1, containing propane and propylene is obtained. b) If necessary, a certain quantity of the other components in gas mixture 1, obtained in the first stage, besides propane and propylene, such as hydrogen and carbon monoxide is separated and/or converted to other compounds, such as water and carbon dioxide. From gas mixture 1, gas mixture 1' is obtained, containing propane and propylene, as well as other compounds, besides oxygen, propane and propylene. c) At the third stage, gas mixture 1 and/or gas mixture 1' as a component, containing molecular oxygen, of gas mixture 2, is subjected to heterogeneous catalysed partial gas-phase oxidation and/or propylene, contained in gas mixture 1 and/or gas mixture 1', undergoes partial gas-phase ammoxidising. Content of butane-1 in gas mixture 2 is ≤1 vol.%. The method increases output of desired products and efficiency of the process.

EFFECT: increased output of desired products and efficiency of the process.

72 cl, 10 ex

FIELD: chemistry.

SUBSTANCE: invention concerns improved method of obtaining at least one product of partial propylene oxidation and/or ammoxidation, propylene selected out of group including propyleneoxide, acrolein, acrylic acid and acrylnitryl, where source substance is propane. Method involves a) at the first stage, homogeneous and/or heterogeneous catalysed dehydration and/or oxydehydration of raw propane in the presence and/or in the absence of oxygen, to obtain gas mix containing propane and propylene; and b) if required, separation of part gas mix 1 obtained at the first stage and its components other than propane and propylene, such as hydrogen, carbon monoxide, or transformation of this part in the other compounds, such as water, carbon dioxide, so that gas mix 1' containing propane and propylene and compounds other than oxygen, propane and propylene is obtained from gas mix 1; and at least one more stage c) heterogeneous catalysed ammoxidation and/or partial gas phase ammoxidation of propylene containing in gas mix 1 and/or gas mix 1' in gas mix 1 or gas mix 1' containing molecular oxygen of gas mix 2, where total C4-hydrocarbon content in gas mix 2 is < 3 volume %.

EFFECT: reduced process performance due to reduced output of target product and enhanced selectivity of carbon oxide generation at the second process stage.

50 cl, 10 ex

FIELD: chemistry.

SUBSTANCE: mixed metal oxide catalyst based on antimonite in a catalytic active oxidation state has the empirical formula: MeaSbbXcQdReOf, where Me is at least one element from the group: Fe, Co, Ni, Sn, U, Cr, Cu, Mn, Ti, Th, Ce, Pr, Sm, or Nd; X is at least one element from the group: V, Mo, or W; Q is at least one element from the group: Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Zr, Hf, Nb, Ta, Re, Ru, Os, Rh, Ir, Pd, Pt, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Tl, Ge, Pb, As, or Se; R is at least one element from the group: Bi, B, P, or Te; and the indices a, b, c, d, e and f denote atomic ratios: a has a value from 0.1 to 15; b has a value from 1 to 100; c has a value from 0 to 20; d has a value from 0 to 20; e has a value from 0 to 10 and f is a number, taken to fulfill the valency requirements of the metals answering for the oxidation degree they have in the composition of the catalyst. Method of obtaining such a catalyst includes the following stages. At first they are subjected to aqueous suspension of Sb2O3 with HNO3 and with one or more compounds of Me, and voluntarily with one or more compounds from the groups: X, Q or R, for obtaining the first mixture (a). The first mixture is then heated and dried to form a solid product (b). After this the solid product is calcinated forming the catalyst. The particular metal oxide catalyst based on antimonite in the catalytic active oxidation state as per the invention has the empirical formula: Ua'FeaSbbMocBieOf, where the indices a, a', b, c, e and f denote atomic ratios: a has a value from 0.1 to 5; a' has a value from 0.1 to 5; b has a value from 1 to 10; c has a value from 0.001 to 0.2; e has a value from 0.001 to 0.2; and f is a number, taken to fulfill the valency requirements of Sb, U, Fe, Bi, and Mo, answering for the oxidation degree they have in the composition of the catalyst. Method of obtaining such a catalyst includes the following stages. At first they are subjected to aqueous suspension of Sb2O3 with HNO3, oxides or nitrates of bismuth and oxides or nitrates of uranium to form the first mixture (a). The first mixture is then heated under temperature and in a period of time, enough for the induction of the process for the formation of the antimonic oxide crystals and formation of the second mixture (b). An aqueous solution of a ferric compound iss then added to the second mixture for the formation of a third mixture (c). The pH of the third mixture is regulated in the range of 7 - 8.5, a precipitate of a hydrated mixture of oxides in the aqueous phase is formed (d). The precipitate is separated from the aqueous phase (e). An aqueous suspension of precipitate components of hydrated mixed oxides is obtained (f). Molybdate is added to the suspension component of hydrated mixed oxides (g). A suspension of hydrated mixed oxides of Molybdate component in the form of dy particles is formed (h). Later the calcination of the dry particles with the formation of the catalyst is carried out (i).

EFFECT: increase in the activity and selectivity of the catalyst.

30 cl, 2 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: invention concerns improved method for obtaining (meth)acrylic acid involving steam phase catalytic oxidation of propylene, propane or isobutylene for production of reaction mix, absorption of oxidised reaction product in water to obtain water solution containing (meth)acrylic acid, concentration of water solution in the presence of azeotropic agent and distillation of obtained (meth)acrylic acid in distillation column to obtaining purified (meth)acrylic acid. During operation of distillation column, including operation interruption and resumption, the column is washed with water, and afterwards azeotropic distillation is performed in the presence of azeotropic agent.

EFFECT: efficient and fast cleaning of distillation column with extraction of valuable substance.

5 cl, 5 dwg, 3 ex

FIELD: heating.

SUBSTANCE: invention concerns improved method of catalytic oxidation in vapour phase which supplies effective removing of reactionary heat, excludes hot spot formation, and supplies effective receipt of base product. Method of catalytic oxidation is disclosed in the vapour phase (a) of propylene, propane or isobutene by the instrumentality of molecular oxygen for receiving (meth)acrolein, and/or oxidation (b) of (meth)acrolein by molecular oxygen for receiving (meth)acryl acid, by the instrumentality of multiple-tubular reactor, contained: cylindrical reactor vessel, outfitted by initial material supply inlet hole and discharge hole for product, variety of reactor coolant pipes, located around the cylindrical reactor vessel and used for insertion the heat carrier into cylindrical reactor vessel or for removing the heat carrier from it, circulator for connection of variety loop pipeline to each other, variety of reaction tube, mounted by the instrumentality of tube reactor lattices, with catalyst. Also multiple-tubular reactor contains: variety of partitions, located lengthways of reaction tubes and used for changing heat carrier direction, inserted into reactor vessel. According to this heat carrier coolant flow is analysed and there are defined zones in reactor which have heat-transfer coefficient of heat carrier less than 1000 W/(m2·K); also reaction of catalytic oxidation is averted in the vapour phase in mentioned zones of reactor and reaction of catalytic oxidation is implemented in the vapour phase in reactor.

EFFECT: receiving of improved method catalytic oxidation in vapour phase which supplies effective removing of reactionary heat, excludes hot spot formation, and supplies effective receipt of base product.

3 cl, 6 dwg, 2 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to an improved method for synthesis of acrolein or acrylic acid or their mixture. Method involves at step (A) propane is subjected for partial heterogenous catalyzed dehydrogenation in gaseous phase to form a gaseous mixture A of product comprising molecular hydrogen, propylene, unconverted propane and components distinct from propane and propene, and then from a gaseous mixture of product from step (A) distinct from propane and propylene at least partial amount of molecular hydrogen is isolated and a mixture obtained after this isolation is used as a gaseous mixture A' at the second step (B) for loading at least into one oxidation reactor and in at least one oxidation reaction propylene is subjected for selective heterogenous catalyzed gas-phase partial oxidation with molecular oxygen to yield as the end product of gaseous mixture B containing acrolein or acrylic acid, or their mixture, and the third (C) wherein in limits of partial oxidation of propylene at step (B) of gaseous mixture B acrolein or acrylic acid or their mixtures as the end product are separated and at least unconverted propane containing in gaseous mixture at step (B) is recovered to the dehydrogenation step (A) wherein in limits of partial oxidation of propylene at step (B) molecular nitrogen is used as additional diluting gas. Method provides significant decreasing of by-side products.

EFFECT: improved method of synthesis.

39 cl, 11 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for synthesis of acrolein and/or acrylic acid from propane and/or propene. Method involves the following steps: (a) isolating propane and/or propene from gaseous mixture A containing propane and/or propene by their absorption with adsorbent; (b) isolating propane and/or propene from adsorbent to form gas B containing propane and/or propene, and (c) using gas B obtained in stage (b) for oxidation of propane and/or propene to acrolein and/or acrylic acid wherein the heterogeneous catalytic dehydrogenation of propane without feeding oxygen is not carried out. Method shows economy and maximal exploitation period of used catalyst without its regeneration.

EFFECT: improved method of synthesis.

12 cl, 7 dwg, 1 ex

FIELD: chemistry of halogenated hydrocarbon, chemical technology.

SUBSTANCE: invention relates to an improved method for synthesis of higher saturated chlorinated acids of the general formula: R(CHCl)nCOOH wherein R means aliphatic hydrocarbon radical comprising 9-22 carbon atoms; n = 1-4. Method involves oxidation of chloroparaffins in the presence of catalyst that is mixed with chloroparaffins in the presence of air oxygen at temperature 120-1250C, and oxidation is carried out with air oxygen at temperature 105-1100C under atmosphere pressure for 30-32 h, and wherein cobalt stearate is used as catalyst taken in the amount 1.5-1.7 wt.-% of the reaction mass. Invention provides increasing rate in carrying out the reaction and simplifying the method.

EFFECT: improved method of synthesis.

5 ex

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