Method of producing (met)acrylic acid or (met)acrolein |
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IPC classes for russian patent Method of producing (met)acrylic acid or (met)acrolein (RU 2349573):
                
 Method for preparing acrylic acid / 2258061
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.
 The method of obtaining acrylic acid / 2119908
 Method of obtaining, at least, one product of partial oxidation and/or ammoxidising of propylene / 2347772
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.
 Method of catalytic oxidation in vapour phase implemented in multiple-tubular reactor / 2331628
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.
 Process for production of acrylic acid via heterogeneously catalyzed partial oxidation of propane / 2308446
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 Mo1VbM1 сM2 вOn (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.
 Method for production of (meth)acrolein and (meth)acrlic acid compounds / 2279424
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.
Method for preparing acrylic acid / 2258061
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.
Method for preparing acrylic acid / 2258061
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.
The method of obtaining acrylic acid / 2119908
Method of obtaining, at least, one product of partial oxidation and/or ammoxidising of propylene / 2347772
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.
 Method of obtaining at least one product of partial propylene oxidation and/or ammoxidation / 2346928
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 %.
Method of preparing catalyst for oxidation and ammoxidation of olefins / 2341327
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).
 Method for obtaining (meth)acrylic acid / 2333194
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.
Method of catalytic oxidation in vapour phase implemented in multiple-tubular reactor / 2331628
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.
Method for preparing acrolein or acrylic acid or their mixture from propane / 2312851
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.
 Method for preparing acrolein and/or acrylic acid / 2285690
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.
Method for production of (meth)acrolein and (meth)acrlic acid compounds / 2279424
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.
 Method for oxidation for preparing alkenes and carboxylic acids / 2276127
Invention relates to the improved method for oxidation of (C2-C4)-alkane and preparing the corresponding alkene and carboxylic acid. Method involves addition of this alkane to contact with molecular oxygen-containing gas in oxidative reaction zone and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity. Each catalyst is effective in oxidation of alkane to corresponding alkene and carboxylic acid resulting to formation of product comprising alkene, carboxylic acid and water wherein the molar ratio between alkene and carboxylic acid synthesized in the reaction zone is regulated or maintained at the required level by regulation the relative amounts of at least two catalyst in the oxidative reaction zone. Also, invention relates to the combined method for preparing alkyl carboxylate comprising abovementioned stage in preparing alkene and carboxylic acid in the first reaction zone. Then method involves the stage for addition of at least part of each alkene and carboxylic acid prepared in the first reaction zone to the inter-contacting in the second reaction zone the presence of at least one catalyst that is effective in preparing alkyl carboxylate to yield this alkyl carboxylate. Also, invention relates to a method for preparing alkenyl carboxylate comprising the abovementioned stage for preparing alkene and carboxylic acid in the first reaction zone and stage for inter-contacting in the second reaction zone of at least part of each alkene and carboxylic acid synthesized in the first reaction zone and molecular oxygen-containing gas in the presence of at least one catalyst that is effective in preparing alkenyl carboxylate and resulting to preparing this alkenyl carboxylate.
 Oxidation process resulting in production of alkenes and carboxylic acids / 2275351
Invention relates to improved C2-C4-alkane oxidation process to produce corresponding alkene and carboxylic acid, which process comprises bringing indicated alkane in oxidation reaction zone into contact with molecular oxygen-containing gas and corresponding alkene and optionally with water in presence of at least one catalyst efficient for oxidation of alkane into corresponding alkene and carboxylic acid. Resulting product contains alkene, carboxylic acid, and water, wherein alkene-to-carboxylic acid molar ratio in oxidation reaction zone is controlled or maintained at desired level by way of controlling alkene and optional water concentrations in oxidation reaction zone and also, optionally, controlling one or several from following parameters: pressure, temperature, and residence time in oxidation reaction zone. Invention also relates to integrated process of producing alkyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone in contact with each other in presence of at least one catalyst effective in production of alkyl carboxylate to produce the same. Invention further relates to production of alkenyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone plus molecular oxygen-containing gas into contact with each other in presence of at least one catalyst effective in production of alkenyl carboxylate to produce the same.
Method of obtaining at least one product of partial propylene oxidation and/or ammoxidation / 2346928
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 %.
 Catalyst, method of its obtaining and method of benzoic acid production / 2335341
Invention concerns organic synthesis field, particularly method of obtaining benzoic acid (C6H5COOH, benzenecarboxylic acid) by catalytic oxidation of benzyl alcohol in hydrogen peroxide solution, as well as catalysts for method implementation, and method of obtaining catalysts. Catalysts of benzoic acid production is nanostructurised bifunctional metallocomplex catalyst acting as oxidation and interphase transport catalyst. It is a complex compound of the general formula Q3{PO4[W(O)(O2)2]4}, where: Q is quadruple ammonium cation [(R1)3N R2]+, where: R1 and R2 contain 8 to 24 carbon atoms. The invention concerns method of obtaining catalyst for benzoic acid production by dissolution of compounds containing phosphor and tungsten in hydrogen peroxide solution with added interphase transport catalyst compound, with phosphor-tungsten heteropolyacids of Keggin or Dawson structure are used as compounds containing phosphor and tungsten, dissolution is performed at the following mol ratio: hydrogen peroxide to tungsten [H2O2]/[W]=15-50, with further addition of quadruple ammonium cation - [(R1)3N R2]+ as interphase transport catalyst, where: R1 and R2 contain 8 to 24 carbon atoms. The invention also concerns method of obtaining benzoic acid by substrate oxidation in hydrogen peroxide in the presence of the catalyst described above.
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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: 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
The technical field to which the invention relates The present invention relates to a method for producing, on which at least one of the substances to oxidize, propylene, propane, isobutylene and (meth)acrolein, effectively catalytically oxidized in the gas phase by molecular oxygen with the formation of (meth)acrolein or (meth)acrylic acid. The level of technology In General, (meth)acrylic acid or (meth)acrolein is continuously receiving such a way that using mnogotranshevogo reactor having multiple reaction tubes, each of which Packed catalyst, propylene, propane, isobutylene or (meth)acrolein, which is a substance for oxidation, catalytically oxidized by molecular oxygen or containing molecular oxygen gas in the gas phase in the presence of mixed (composite) oxide catalyst. In the reaction tube temperature distribution is formed in the flow direction (in the direction of the axis of the tube) process gas consisting of oxidizable substances and molecular oxygen or containing molecular oxygen gas. Usually the temperature peak exists on the inlet side of the stream. Figure 3 shows the change of temperature distribution in the direction of the axis of the tube, resulting from the continuous the main process. As a continuous process, the catalyst activity is disturbed and a particularly large decrease in catalyst activity is observed on the inlet side of the stream. In accordance with this, the reaction rate in this area is reduced, which results in decrease of the allocated due to the reaction heat. With regard to gas flow at a more remote from the entrance side than the above, as a quantitative measure of reaction in the inlet side of the flow decreases as the concentration of the raw material, which serves becomes higher, the quantitative indicators of the reaction increases, and increases the amount of heat emitted. However, the total quantitative reaction throughout the reaction tube is reduced. At this time, the position of the temperature peak in the direction of the axis of the tube (hereinafter referred to as the position of the peak) is shifted in the direction of the exit flow, and the peak temperature decreases the temperature distribution changes from a to b). In accordance with the situation, as long as the process is carried out so that the temperature (reaction temperature) was increased, this resulted in the return position of the peak in the direction of the input stream and increasing the maximum temperature, which led to the improvement of catalytic activity to maintain the yield of the product (the distribution of temperature changes from b to c'). Disclosure of invention The problem related to the conventional process, is that the change in peak temperature from the beginning of the process is so large that the load on the catalyst near the peak position becomes significant, and the catalytic activity deteriorates rapidly. In accordance with this, the coolant temperature increases to the reactivation of the catalytic activity, and thus reduce product yield due to deactivation of the catalyst can be compensated within a short period. But then, after a certain time the catalytic activity locally is extremely reduced, which results in a rapid decrease in product yield. The present invention relates to a method for producing (meth)acrolein or (meth)acrylic acid by this method using mnogotranshevogo reactor having multiple reaction tubes, each of which Packed catalyst, propylene, propane, isobutylene or (meth)acrolein, catalytically oxidized in the gas phase with molecular oxygen or containing molecular oxygen gas in the presence of a mixed oxide catalyst, in which (meth)acrolein or (meth)acrylic acid can be obtained stably, with high yield and without local deactivation of the catalyst. The authors invented the I after intensive study found that when to overcome the decrease of catalytic activity caused by the continuous process, without excessive temperature increase of the coolant to maintain the yield of the reaction peak temperature of the catalyst to move within a certain range in the direction of the exit flow, thereby avoiding local deactivation of the catalyst, (meth)acrolein or (meth)acrylic acid can be obtained stably and with high yield, and came to the present invention. In other words, in accordance with the invention proposes a method of obtaining a (meth)acrolein or (meth)acrylic acid and thus can be achieved, the task of the aforementioned inventions. That is a method by which the (meth)acrylic acid or (meth)acrolein is obtained using mnogotranshevogo reactor with a fixed catalyst bed, which has a number of reaction tubes provided with at least one of the catalyst layer in the direction of the axis of the tube, and allows the coolant to regulate the temperature of the reaction at the outer side of the flow of the reaction tube, the reaction tube carry out gas-phase catalytic oxidation of at least one of the types of oxidizable substances, propylene, propane, isobutylene and (meth)acrolein, molecular oxygen or gas is, containing molecular oxygen, characterized in that in the beginning of the process the temperature difference between the coolant temperature and the peak temperature of the catalyst is set in the range from 20 to 80°and during the process peak temperature T (° (C) catalyst in the direction of the tube axis satisfies the following equation 1.
(In equation 1 L, T0X and X0respectively denote the length of the reaction tube, the peak temperature of the catalyst in the direction of the axis of the tube at the beginning of the process, the length up to the situation, which shows the peak temperature T at the entrance of the reaction tube and the length up to the situation, which shows the peak temperature T0at the entrance of the reaction tube.) Brief description of drawings Figure 1 shows a schematic cross section of a variant of implementation mnogotranshevogo reactor heat exchanger of the type used for gas-phase catalytic oxidation, in accordance with the present invention; Figure 2 presents a graph showing the change in the temperature distribution caused by the continuous process, in the direction of the tube axis of the reactor tube of the invention; and Figure 3 is a graph showing the distribution of temperature is tours, caused by the continuous process, in the direction of the axis of the tube of the tubular reactor. In the drawings, each of the reference numbers 1b and 1C denotes a reaction tube; 2 denotes a reactor; each of 3A and 3b denotes a circular pipe of the pipeline; each of the 3A' and 3b' denotes a circular pipe of the pipeline; 4A denotes an output device for release of the product; 4b denotes a hole for supply of raw material; each of 5A and 5b denotes the lattice for pipes; each of 6A and 6b denotes a guide wall with a window; each of 6A' and 6b' refers to the guide wall with a window; 7 denotes a circulation pump; each of 8A and 8A' denotes a pipe for supplying fluid; each of 8b and 8b' denotes a pipe for discharging the fluid; each of the 11, 14, and 15 denotes a thermometer; each of the links a, b, c, and c' denotes the temperature distribution; X1- the position of the entrance of the reaction tube (inlet process gas); and X2- the position of the outlet of the reaction tube (exit process gas). The best way of carrying out the invention Below the present invention will be described in detail. The present invention is a method by which using mnogotranshevogo reactor with a fixed catalyst bed, which has a structure consisting of many Rea the operating tubes, equipped with at least one catalyst bed in the direction of the axis of the tube, and which allows the coolant to regulate the temperature of the reaction to the outside of the flow of the reaction tubes in the reaction tubes provide continuous gas-phase catalytic oxidation of at least one type of substance for oxidation of propylene, propane, isobutylene and (meth)acrolein molecular oxygen or gas containing molecular oxygen, to obtain a (meth)acrylic acid or (meth)acrolein. The temperature difference at the beginning of the process between the coolant temperature and the peak temperature of the catalyst is set in the range from 20 to 80°and preferably in the range from 20 to 70°C. coolant Temperature, shown above represents the temperature at the entrance, through which the coolant is fed into the reactor. If in the beginning of the process the temperature of the coolant is adjusted so that in the reaction tubes to set the temperature difference with a peak temperature of the catalyst in the above-mentioned range, the localization of the exothermic reaction can be suppressed. As a result, the catalyst activity can largely be protected from local deterioration. See this as a phenomenon in which the temperature distribution of the catalyst according to the accordance with the direction, in which process gas flows (in the direction of the axis of the tube, the shape of the peak temperature existing in the inlet side of the stream locally has no protrusions, and the transition to the output side of the stream, and the lower temperature peak decreases as long as you continue the process. The actual temperature difference between the observed peak temperature, as specified above, and the temperature of the coolant in the beginning of the process is preferably in the range from 20 to 80°s and more preferably in the range from 20 to 70°C. Even if the coolant temperature is set as described above to start the process by continuing the process of reducing the peak temperature caused by decreased activity of the catalyst, and transition (shift) position of the peak cannot be avoided. In accordance with this invention in the process create the peak temperature T (° (C) catalyst in the direction of the axis of the tube, satisfying the equation 1, and preferably the following equation 2. In this case, if the temperature is changed, the peak temperature can be adjusted and specifically, if the temperature of the coolant increases, the peak temperature T can be increased and the position of the peak can be shifted in the direction of the input stream.
(In equation 1 L, T0X and X0respectively mean: the length of the reaction tube (unit: mm), the peak temperature of the catalyst in the direction of the axis of the tube at the beginning of the process (unit: ° (C), the length from the entrance of the reaction tube up to the situation, which shows the peak temperature T (unit: mm)and the length from the entrance of the reaction tube up to the situation, which shows the peak temperature T0(unit: mm)). In the case where L·{|T-T0|/(X-X0)} is too large, the change of position of the temperature peak is too small to cause localized areas of deactivation of the catalyst. Accordingly desirable that the value of L·{|T-T0|}/(X-X0)} was more than 300. In contrast, if the value of L·{|T-T0|/(X-X0)} is too small, the localization of deactivation of the catalyst can be avoided, however, since the total reaction amount is reduced, it is not desirable that the value of L·{(|T-T0|)}/(X-X0)} was less than 35. Figure 2 shows the change of temperature distribution of the catalyst in the direction of the axis of the tube, when the peak temperature T satisfies the equation 1 in a continuous process. The fact that the peak temperature T satisfies the equation 1 means that figure 2 of the region, in which the peak temperature T is shifted, is in a certain area (area R). For example, the temperature distribution at the beginning of the process changes to the distribution of temperature, as the process continues. Thus, if the peak temperature T to adjust so that the peak was within a certain range during the process, the change in peak temperature T can be reduced, that is, by preventing the concentration of stress on the catalyst having reduced activity, thereby the activity of the catalyst can be protected from local reduction. In accordance with this for a long time, it is possible to stably obtain a (meth)acrylic acid or (meth)acrolein in high yield. In order for the process to create the peak temperature T satisfying the equation 1, it is desirable to regulate the peak temperature T so that the difference between the peak temperature T and the temperature can be preferably in the range from 20 to 80°s and more preferably in the range from 20 to 70°C. It will be further explained by way of reaction, the reactor, catalyst and so on, which is used to produce (meth)acrylic acid or (meth)acrolein gas-phase catalytic oxidation of the raw material. In recent years, the number of production AK the sludge acid from propylene and methacrylic acid from isobutylene (collectively referred to as (meth)acrylic acid) is rapidly expanding with the increase in their consumption. In accordance with this worldwide built a lot of units, and the scale of production of each facility increased to one hundred thousand tons or more per year. Scale production plant is the reason for the need to increase the number of products with each oxidation reactor. Accordingly, the load on the reactor gas-phase catalytic oxidation used for propane, propylene or isobutylene, and the catalyst becomes significant. This puts requirements to the operational conditions, which can maintain the stability of the catalyst under high load. In the invention method, which, by means mnogotranshevogo reactor, which includes a cylindrical reactor vessel having an opening for flow of raw materials and the opening for discharge of the product; many circular pipelines, which are located on the outer side of the cylindrical reactor and used for the introduction or use of the fluid in the cylindrical housing of the reactor or outside it; a circular device that connects many of circular pipes with each other; many reaction tubes, which are fixed with many bars for pipe reactor containing a catalyst; and many of the guides of the partitions to change napravleniyami coolant, introduced into the reactor vessel in the direction of the length of the reaction tube, oxidizable raw material oxidizes containing molecular oxygen gas in accordance with an adapted gas-phase catalytic oxidation in the reaction tubes filled with an oxidation catalyst, such as catalyst on the basis of the Mo-Bi and/or a catalyst based on Mo-V. The invention is a method of catalytic gas-phase oxidation, in which propylene, propane, isobutylene or (meth)acrolein or a mixture thereof as a substance for oxidation catalytic oxidized in the gas phase containing molecular oxygen gas to obtain a (meth)acrolein or (meth)acrylic acid. From propylene, propane and isobutene can be obtained (meth)acrolein, (meth)acrylic acid or both products. In addition, from (meth)acrolein get (meth)acrylic acid. In the invention "process gas" means gas that participates in gas-phase catalytic oxidation of a substance for oxidation of gaseous material raw material gas containing molecular oxygen, and the resulting product. "Raw material" is a synonym of the substance for oxidation. The composition of the gaseous raw material In Novotrubny reactor used for gas-phase catalytic oxidation, mainly introducing the gas mixture, at least, one of the CSOs of the types of substances for oxidation, propylene, propane, isobutylene and (meth)acrolein as gaseous material raw material gas containing molecular oxygen, and water vapor. In the invention, the concentration of oxidizable substances in the mixed gas is in the range from 6 to 10 mol.%, so oxygen is present in the range from 1.5 to 2.5 molar ratio on the concentration of oxidizable substances and so that the water vapor present in the range from 0.8 to 5 molar ratio. Novotrubny reactor Gas-phase catalytic oxidation according to the invention, which is used Novotrubny reactor with a fixed catalyst bed, is widely used, when at least one species oxidizable substances, propylene, propane, isobutylene and (meth)acrolein, in the presence of a mixed oxide catalyst using molecular oxygen or gas containing molecular oxygen, get a (meth)acrylic acid or (meth)acrolein. Novotrubny reactor with a fixed catalyst bed for use in the invention are widely used in industry, and special restrictions for him missing. The reactor or similar device that can be used in the method of the invention, will be described with reference to figure 1. Figure 1 shows a schematic cross-section one what about the case for mnogotranshevogo reactor heat exchanger type which is used in the method of gas-phase catalytic oxidation according to the invention. In case 2 mnogotranshevogo reactor the reaction tube 1b and 1C fixed to the grids of tubes 5A and 5b. The inlet of the raw material, through which the injected gaseous raw material, and an aperture for discharge of the product through which the product is removed, shown as 4A or 4b. If the process gas flow and coolant flow are counter flows, there are no specific restrictions on the direction of flow of the process gas. However, in figure 1 due to the fact that the direction of flow of the coolant in the reactor vessel is shown as the upward flow, 4b indicates the inlet of the raw materials. On the outer edge of the reactor vessel has a circular pipe 3A for introducing coolant. The coolant, which is under the pressure created by the circulating pump 7 to the coolant rises in a circular pipe 3A of the inner side of the reactor. Each of the sets of guide walls 6A, having a window near the center of the reactor, and each of the sets of guide walls 6b, having a window on the outer edge of the reactor vessel in another method, the flow direction change, and the heat flow is returned from the circular pipe 3b to circulationaha pump. Part of the heat carrier, which took the heat of reaction out of the discharge pipe located in the upper part of the circulating pump 7, is cooled by a heat exchanger (shown here in the drawing) and is introduced again from the pipeline coolant 8A in the reactor. The temperature of the coolant is adjusted, when either the temperature or the rate of return flow of the coolant introduced from the supply line carrier 8A, regulate by means of the control thermometer 14. Temperature control of the coolant, however, depending on the characteristics of the used catalyst is carried out so that the difference of the temperatures of the coolant pipe coolant 8A and the coolant discharge pipe coolant 8b may be in the range from 1 to 10°and preferably in the range of from 2 to 6°C. thermometer 11 is inserted into the reaction tube installed in the reactor, the signals are transmitted to the outer side of the reactor and thereby register the temperature distribution of the catalytic layer in the direction of the axis of the tube reactor. thermometer is inserted into each of the tubes of the reactor and one thermometer in the direction of the axis of the tube, usually see the temperature at 5 points or more, preferably 10 points or more and more preferably 20 points or more. You can use a thermometer, which is meet the variable part for temperature measurement and can measure in an unlimited number of points. Catalyst As the catalyst used for gas-phase catalytic oxidation to obtain (meth)acrylic acid or (meth)acrolein used such that use in the first stage reaction, in which the olefin converted into an unsaturated aldehyde or an unsaturated acid, and catalysts that are used in the second stage reaction in which unsaturated aldehyde is transformed into unsaturated acid. In the reaction of gas-phase catalytic oxidation as mixed oxide catalyst on the basis of the Mo-Bi, which is used in the first half reaction, mainly for the production of acrolein (reaction conversion of olefins to unsaturated aldehyde or unsaturated acid)catalysts correspond to the General formula (I), which can be represented as follows: MoaWbBicFedAeBfCgDhEiOx(I) In the General formula (I), A, B, C, D, E, and O respectively represent at least one kind of element selected from Nickel and cobalt, at least one kind of element selected from sodium, potassium, rubidium, cesium and thallium, at least one kind of element selected from alkaline earth metals, at least one kind of element selected from phosphorus, tellurium, antimony, tin, cerium, lead, niobium, Marg the NCA, arsenic, boron and zinc, at least one kind of element selected from silicon, aluminum, titanium and zirconium, and oxygen. Besides a, b, c, d, e, f, g, h, i and x, respectively, denotes the atomic relations of Mo, W, Bi, Fe, A, B, C, D, E, and O in the case of a=12, 0≤b≤10, 0<c≤10 (preferably 0.1 to≤≤10), 0<d≤10 (preferably 0,1≤d≤10), 2≤e≤15, 0<f≤10 (preferably 0,001≤f≤10), 0≤g≤10, 0≤h≤4 and 0≤i≤30, and x denotes a variable determined by the oxidation state of the elements. When gas-phase catalytic oxidation, as mixed oxide catalyst based on Mo-V used in the second half of the way in which oxidize acrolein to acrylic acid (reaction conversion of unsaturated aldehyde to unsaturated acid), the catalyst corresponded to the General formula (II), which can be presented below as follows: MoaVbWcCudXeYfOg(II) In the General formula (II) X, Y and respectively represents at least one kind of element selected from Mg, Ca, Sr and BA, at least one kind of element selected from Ti, Zr, Ce, Cr, Mn, Fe, Co, Ni, Zn, Nb, Sn, Sb, Pb and Bi, and oxygen. In addition, a, b, c, d, e, f, and g respectively denote the atomic relations of Mo, V, W, Cu, X, Y and, in the case of a=12, 2≤b≤14, 0≤c≤12, 0<d≤6, 0≤e≤3, 0≤f≤3 and g represents the t a value that defined oxidation state of the respective elements. The above-mentioned catalysts produced according to the method described in Japan patent JP-A-63-54942, JP-B-6-13096 and JP-B-6-38918. Hereinafter will be described secondary points of the invention. The stage of obtaining acrylic acid As the stages of production of acrylic acid, for example, below the stage (i) to (iii). (i) conduct phase oxidation, in which the propane, propylene and/or acrolein is subjected to gas-phase catalytic oxidation stage capture, in which a gas containing acrylic acid, from the stage of oxidation in contact with water so as to recover the acrylic acid in the aqueous solution of acrylic acid, and the stage of extraction, in which acrylic acid is extracted from the aqueous solution of acrylic acid using prepared appropriate extractant, then produce acrylic acid from it, cleaning is carried out in the stage of purification of the Michael adduct of acrylic acid with a high-boiling solvent containing a polymerization inhibitor used in each stage, is fed into the column of the decomposition reaction as a raw material for extraction of valuable products, and valuable products are served at any of the stages after stage capture; (ii) conduct phase oxidation, in which the PCC is len, propane and/or acrolein is subjected to gas-phase catalytic oxidation to obtain acrylic acid, phase trapping, in which the gas containing acrylic acid, in contact with water to acrylic acid to catch in the form of an aqueous solution of acrylic acid, stage azeotropic separation, in which an aqueous solution of acrylic acid is distilled in the column azeotropic separation in the presence of an azeotropic solvent, after which the crude acrylic acid removed from the bottom of the column, and the stage of separation of acetic acid, in which acetic acid is removed and cleaned of high boiling impurities, then the Michael adduct of acrylic acid after cleaning and high-boiling solvent containing the polymerization inhibitor used in the stages of receipt, served in the column of the decomposition reaction as raw materials for extraction of valuable products, and valuable products served at any stage after stage of recovery; and (iii) conduct phase oxidation, in which acrylic acid is obtained gas-phase catalytic oxidation of propylene, propane and/or acrolein, the stage of capture/separation, in which a gas containing acrylic acid, in contact with an organic solvent for recovery of acrylic acid in the form of a solution of acrylic acid in the organic will dissolve the Le, through the simultaneous removal of water, acetic acid, etc., phase separation, in which acrylic acid is recovered from solution of acrylic acid in an organic solvent, the stage in which the high-boiling solution containing the adduct of Michael acrylic acid, an organic solvent and a polymerization inhibitor used in these stages of receipt, served in the column of the decomposition reaction as a raw material for extraction of valuable products, and valuable products served at any stage after stage of capture, and the stage in which the organic solvent receive partially purified. Thus, the obtained acrylic acid or esters of acrylic acid, for which the raw material is acrylic acid, is used in various application areas. In particular, it is possible to call overabsorbed polymer coagulant, adhesives, pressure-sensitive material for coating, adhesive and modifiers fibers. Example Further, the present invention will specifically be explained with reference to example and comparative example. However, the invention is not limited to this example. Catalyst 400 wt. parts of pure water was dissolved by heating to 94 wt. part of paramolybdate ammonium. In another case, a 7.2 wt. parts of ferric nitrate, 25 wt. cha the TEI of cobalt nitrate and 38 wt. parts of Nickel nitrate was dissolved by heating to 60 wt. parts of purified water. These solutions were mixed under vigorous stirring and a solution that is similar to the mist. Next, 0.85 wt. parts of borax and 0.36 wt. parts of potassium nitrate were dissolved by heating in 40 parts of purified water, followed by adding to the suspension. At the next stage was added 64 wt. part of the particles of silicon oxide, followed by stirring. Then to this suspension was added to 58 wt. parts of nederbeat bismuth, which is pre-mixed with 0.8 wt.% Mg, and the suspension was stirred to obtain a mixture. Then the suspension was heated for drying, heat treatment was carried out at a temperature of 300°C for 1 h in air. The resulting solid particles were molded into tablets having a diameter of 5 mm and a height of 4 mm, the pressing of tablets using a molding machine, followed by sintering at a temperature of 500°C for 4 hours to obtain catalyst for the first stage of the method. The catalyst for the first stage of the method consisted of a mixed oxide based on the Mo-Bi, with the ratio of the component parts of the catalytic powder in accordance with the formula Mo12Bi5Ni3Co3Fefor 0.4Naof 0.2Mgfor 0.4Bof 0.2Ka 0.1Si24Ox(x is a value determined in C is depending on the oxidation state of the metal). Obtaining acrylic acid or acrolein of propylene In the present example used the same Novotrubny reactor, as shown in figure 1. In particular, we used Novotrubny reactor having 10000 reaction tube of stainless steel, having a length of 3.5 m and an internal diameter of 27 mm As the heat used a molten salt mixture of nitrates (nitrate)supplied from the lower part of the reactor and discharged from the upper part of the reactor to circulate. The coolant is partially unloaded from 8b to cool, then return it to 8A. In this case, the temperature of the coolant fed to the reactor was regulated, and the temperature measured using a thermometer 15. As for the catalyst, which filled each reaction tube, the catalyst, which was obtained by mixing the catalyst for the first half of the way and made of silicon oxide balls, which have no catalytic activity, with a diameter of 5.5 mm in a volume ratio of 7:3, was filled to the height of the filled layer in each reaction tube could be of 2.9 m Gaseous raw material was applied from the upper part of the reactor so that it was countercurrent to the movement of the carrier, and was at 60 kPa (pressure gauge)is a gaseous raw material containing propileno concentration of 9.5 mol.%, molecular oxygen at a concentration of 14.5 mol.%, the water of 9.5 mol.% and nitrogen, with 66.5 mol.% (the interval of measurement points: 80 mm on the inlet side of the flow and 240 mm at the outlet side of the flow), and in the direction of the axis of the tube has 20 points for measurement, was injected into each reaction tube to change the temperature distribution. Example The process started by filling the reactor again obtained catalyst, as described above, and serving as a raw material propylene, and 1 month after that, the temperature of the coolant at the entrance was set at 335,2°C. At this time, the peak temperature of the catalytic layer was 390°C, the position of the peak was 220 mm from the entrance of the catalytic layer, the reaction rate of the conversion of raw material was 98,3% and the overall yield of acrylic acid and acrolein was 92.6 per cent. In addition, the calculated peak temperature and the peak position of the catalytic layer of maximum multipoint temperature thermometer used to measure temperature, and temperature, as measured at the positions before and after this position, using the quadratic function that passes through these three points. On the basis of conditions (T=394°and X0=220 mm), the process continued, and the temperature was regulated so as to increase the peak temperature could be in the range of L×{|T-T 0|/(X-X0)}=60±10. After 11 months from the beginning of the process the temperature of the coolant at the entrance was 335,6°C, the peak temperature of the catalytic layer was 392,4°C, the position of the peak was 320 mm (L×{|T-T0|/(X-X0)}=58) from the inlet side of the catalytic layer, the reaction rate of the conversion of raw materials propylene was 98,0% and the overall yield of acrylic acid and acrolein was 92.2 per cent. When a continuous process for 11 months was repeated three times, with the shutdown period of one month, in between them, the temperature of the coolant at the entrance was sauce 337,1°C, the peak temperature of the catalytic layer was 399,5°C, the position of the peak was 550 mm (L×{|T-T0|/(X-X0)}=58) from the inlet side of the catalytic layer, the reaction rate of the conversion of raw materials was 97.4% and the total yield of acrylic acid and acrolein was 90.4 percent. Comparative example The process in the reactor began similar to a given example. 1 month after the start of the process the temperature of the coolant at the entrance was set at 335,0°C. At this time, the peak temperature of the catalytic layer was 388°C, the position of the peak was 230 mm from the entrance of the catalytic layer, the reaction rate of the conversion of raw materials propylene was 98.4% and the total yield of acrylic acid and acrolein was of 92.7%. Based on the above-mentioned conditions (T0=388°and X0=230 mm) process food is reaped with the coolant temperature, regulated so that the reaction rate of the conversion of raw materials propylene could be of 98.2±0,3%. After 11 months from the beginning of the process, the temperature of the coolant at the entrance was 336,2°C, the peak temperature of the catalytic layer was 393,0°C, the position of the peak was 260 mm (L×{|T-T0|/(X-X0)}=580) from the entrance of the catalytic layer and the total yield of acrylic acid and acrolein was 91,9%. In addition, after continuous process for 11 months, repeated three times, with the shutdown period between one month, the coolant temperature at the entrance was 341,9°C, the peak temperature of the catalytic layer was 405,4°C, the position of the peak was 240 mm (L×{|T-To|/(X-X0)}=609) from the entrance of the catalytic layer and the total yield of acrylic acid and acrolein decreased to 87.8%. Although the invention has been described in detail and reference is made to specific variations in its implementation, for specialists in this area it is obvious that it is possible to make various changes or modifications not beyond the nature and scope of this invention. This application is based on patent application of Japan (Application No. 2004-108736), registered on 1 April 2004, the full contents of which are incorporated herein by reference. Industrial applicability In accordance with the method of the present invention, without assumptions the considerable reduction of the activity of the catalyst, Packed in the reaction tube, (meth)acrylic acid or (meth)acrolein can be obtained stably and with high output. A method of obtaining a (meth)acrylic acid or (meth)acrolein, which using mnogotranshevogo reactor with a fixed layer having a design that has many reaction tubes equipped with at least one catalyst bed in the direction of the axis of the tube, and allowing the coolant to regulate the temperature of the external side of the flow of the reaction tube, the reaction tube carry out gas-phase catalytic oxidation of at least one type of oxidizable substances, propylene, propane, isobutylene and (meth)acrolein molecular oxygen or gas containing molecular oxygen, characterized in that in the beginning process temperature difference between the coolant temperature and the peak temperature of the catalyst is set in the range from 20 to 80°and during the process peak temperature T(° (C) catalyst in the direction of the tube axis satisfies the following equation 1:
in which L, T0X and X0accordingly represents the length of the reaction tube, the peak temperature of the catalyst in the direction of the axis of the tube at the beginning of the process, the length of the EAP is ot to the position which shows the peak temperature T at the entrance of the reaction tube, and the length up to the situation, which shows the peak temperature T0at the entrance of the reaction tube.
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