CN108101872B - Catalyst grading method for producing maleic anhydride by oxidizing n-butane - Google Patents

Catalyst grading method for producing maleic anhydride by oxidizing n-butane Download PDF

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CN108101872B
CN108101872B CN201611045758.2A CN201611045758A CN108101872B CN 108101872 B CN108101872 B CN 108101872B CN 201611045758 A CN201611045758 A CN 201611045758A CN 108101872 B CN108101872 B CN 108101872B
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catalyst
butane
reaction
vanadium
phosphorus
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CN108101872A (en
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王海波
刘新宇
宋丽芝
侯学伟
勾连科
程谨
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China Petroleum and Chemical Corp
Sinopec Fushun Research Institute of Petroleum and Petrochemicals
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China Petroleum and Chemical Corp
Sinopec Fushun Research Institute of Petroleum and Petrochemicals
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
    • C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
    • C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
    • C07D307/56—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D307/60—Two oxygen atoms, e.g. succinic anhydride
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    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/14—Phosphorus; Compounds thereof
    • B01J27/186—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J27/195—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with vanadium, niobium or tantalum
    • B01J27/198—Vanadium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration

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Abstract

The invention discloses a catalyst grading method for producing maleic anhydride by oxidizing n-butane. N-butane and air are mixed, the obtained mixed reaction gas flows through more than three vanadium-phosphorus-oxygen catalyst beds which are connected in series in a parallel flow manner, and the mixed reaction gas contacts with a vanadium-phosphorus-oxygen catalyst to react under the condition of oxidation reaction; the more than three catalyst beds connected in series are graded and filled according to the tendency that the P/V molar ratio of the catalyst is low, high and low in sequence according to the contact sequence of the catalyst beds and the mixed reaction gas, so that the activity distribution of the catalyst is balanced, and the activity of the catalyst is fully exerted. The method can improve the n-butane concentration in the feeding material, reduce the reaction hot spot of the bed layer, ensure the temperature distribution of the bed layer to be even, effectively inhibit the occurrence of side reaction, improve the product selectivity and increase the yield of the maleic anhydride product.

Description

Catalyst grading method for producing maleic anhydride by oxidizing n-butane
Technical Field
The invention relates to a method for preparing maleic anhydride by n-butane, in particular to a method for preparing maleic anhydride by oxidizing n-butane with catalyst grading, which can be used for a reaction process for preparing maleic anhydride by oxidizing n-butane by adopting a fixed bed process.
Background
Maleic anhydride is called maleic anhydride for short, and maleic anhydride is an important organic chemical raw material, is second only to phthalic anhydride and acetic anhydride, is the third largest organic anhydride in the world, and is widely used in the industries of petrochemical industry, food processing, medicines, building materials and the like. Specific applications include the manufacture of unsaturated polyester resins, alkyd resins, maleic acid (maleic acid), fumaric acid (fumaric acid), as well as pesticides, coatings, glass fiber reinforced plastics, lubricating oil additives, papermaking chemical additives, surfactants, and the like. The process for producing 1, 4-butanediol by esterification and low-pressure hydrogenation of maleic anhydride by a new method is disclosed, so that the 1, 4-butanediol, tetrahydrofuran and gamma-butyrolactone which are fine chemical intermediates with high added values are important raw materials, and the application field is rapidly expanded.
Benzene oxidation method and n-butane oxidation method are two main production methods for producing maleic anhydride, wherein benzene oxidation method is the earliest applied process, the reactor and catalyst technology are mature, but because the price of raw material benzene is relatively expensive, the generated environmental pollution is relatively serious, and the defects are gradually shown. The process for preparing maleic anhydride by the n-butane oxidation method of Monsanto company is industrialized for the first time in 1974, and the process has the advantages of low cost of raw materials, small environmental pollution and low manufacturing cost of maleic anhydride, and is a main route for global maleic anhydride production at present. The preparation of the maleic anhydride by the selective oxidation of n-butane can be divided into production processes such as a fixed bed, a fluidized bed, a moving bed and the like.
At present, in the production of maleic anhydride by oxidizing n-butane, the butane raw material utilization rate of a fixed bed process is high, the product quality is stable, and the operation is simple and convenient, so the method becomes a main method for producing maleic anhydride, but in the production process of the fixed bed mode, due to the characteristic of strong heat release of oxidation reaction, the reaction heat of the main reaction for generating maleic anhydride is 1236KJ/mol, and the side reaction for generating CO2The CO reaction heat is 2656KJ/mol and 1521KJ/mol respectively, so that the molten salt which is circulated in the jacket of the reactor from the outside is adopted in the industrial production to remove the reaction heat, but hot spots exist on the local part of the catalyst and are difficult to be optimally controlled, and the existence of the hot spots can generate the performance of the catalystAdverse effects are generated, so that the stabilization of the hot spot in the reaction process becomes the key of the control of the reaction process, and further, the conversion rate of butane, the selectivity of maleic anhydride, the yield of the product maleic anhydride and the stability of the catalyst are directly influenced by the height of the hot spot of the catalyst bed. On the other hand, since the lower explosion limit of butane in air is 1.5% (v), the industrial production usually adopts butane feed concentration of 1.65% (v) for reaction, and the highest butane feed concentration is not more than 1.8% (v), and the industrial process and characteristics of maleic anhydride production device by 2 ten thousand tons/year of normal butane oxidation of petrochemical company of Lanzhou, such as rhizoma cluniae [ J ] and the like [ J ] is]Petrochemical technology and applications, month 7 in 2008, vol twenty-sixth, fourth, indicate that the volume fraction of n-butane in the production of maleic anhydride is from the first 1.0% and finally up to 1.65%, and normal production is maintained at this concentration.
The vanadium phosphorus oxygen catalyst is considered to be the best industrial catalyst in the process of preparing maleic anhydride by oxidizing n-butane, the selective oxidation reaction of n-butane by the vanadium phosphorus oxygen catalyst is a typical representative of a large class of hydrocarbon selective oxidation reaction carried out according to a redox (Re-dox) mechanism, the process of chemical reaction relates to the transfer of 14 electrons, wherein the electron removal on 8 hydrogen atoms and the electron insertion on 3 oxygen atoms are included, the exploration of the reaction mechanism is always the hotspot of the research of the vanadium phosphorus oxygen catalyst, the vanadium phosphorus oxygen catalyst is a complex catalyst system, the physical property and the structure of the vanadium phosphorus oxygen catalyst have great relation with the preparation method, the physical property and the structure of the vanadium phosphorus oxygen catalyst have great influence on the catalytic performance, in 1985, Hodnet in CATAL. REV. -SCI.ENG,27(3) 373-424(1985) summarizes the preparation method of various precursors of the vanadium phosphorus oxygen catalyst for preparing maleic anhydride by oxidizing n-butane, and becomes the classic basis for the research of the vanadium phosphorus oxide catalyst.
Hodnett summarizes that the P/V ratio of the catalyst, the addition of the auxiliary agent, the activation method of the catalyst, and the like all have obvious effects on the performance of the catalyst.
B.K HODNETT conducted extensive studies on the effect of the P/V ratio in a vanadium phosphorus oxide catalyst on the properties and composition of the catalyst and the catalytic performance in applied Catalysis, 6 (1983)231-244, and the results showed that the P/V ratio of the catalyst had a significant effect on the estimated valence of vanadium in the catalyst, with the P/V ratio increasing from 0.94 to 1.07 and the average valence of vanadium in the catalyst decreasing from 4.97 to 4.04.
USP4,632,915 provides a method for preparing and activating a vanadium-phosphorus-oxygen catalyst, which comprises the steps of adding isobutanol, phosphoric acid (100%), vanadium pentoxide, lithium chloride and iron powder into a stirring reaction kettle with a reflux cooler under cooling, introducing hydrogen chloride gas, refluxing for more than 2.5 hours at 102 ℃ to obtain a catalyst precursor, drying, roasting and forming, wherein the activation process comprises the steps of firstly increasing the activation temperature of the catalyst from 230 ℃ to 280 ℃ in an air atmosphere containing 1.8% of water at a heating rate of 3 ℃/min, then adding n-butane with the molar content of 0.6% into the air atmosphere, continuously increasing the activation temperature to 400 ℃ at a heating rate of 1 ℃/min and keeping the temperature for 1 hour, then keeping the temperature for 5 hours in a nitrogen atmosphere, and finishing the activation. The performance of the activated catalyst is evaluated, and the reaction result is as follows: the conversion rate of butane is more than 78.1 percent, and the molar yield of the maleic anhydride is 54.5 percent.
USP4,855,459 provides a preparation method for preparing maleic anhydride by n-butane oxidation, which is carried out by adopting a method of diluting and filling inert silicon-aluminum balls and a catalyst, and the purposes of reducing the reaction hot spot temperature, improving the selectivity of the maleic anhydride and improving the yield of the maleic anhydride are achieved by diluting and filling the hot spot generating part of a reaction tube, and meanwhile, the stabilization period of the catalyst is prolonged, but the adverse factor is the addition of inert materials, so that the effective volume of a reactor is reduced, and the production efficiency is also reduced.
In the existing technology for preparing maleic anhydride by oxidizing n-butane through a fixed bed, catalysts with different activities are respectively filled in a reactor along the flow direction of reactants, so that the catalytic activity is changed along the feeding direction according to the reaction requirement when the catalysts are filled, the control of the oxidation reaction is realized, the feeding concentration of the n-butane serving as a reaction raw material is improved to more than 2.0 percent, and the method for increasing the product yield is not reported so far.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a catalyst grading method for producing maleic anhydride by oxidizing n-butane, so as to improve the n-butane concentration in reaction gas, reduce or even eliminate the hot spot problem of a catalyst bed layer and prolong the service life of the catalyst.
The invention relates to a catalyst grading method for producing maleic anhydride by oxidizing n-butane, which comprises the following steps:
n-butane and air are mixed, the obtained mixed reaction gas flows through more than three vanadium-phosphorus-oxygen catalyst beds which are connected in series in a parallel flow manner, and the mixed reaction gas is contacted with a vanadium-phosphorus-oxygen catalyst for reaction under the condition of oxidation reaction; according to the contact sequence with the mixed reaction gas, the P/V (phosphorus/vanadium) molar ratio of the catalyst in more than three catalyst bed layers connected in series tends to be lower, higher and lower in sequence.
The method of the invention comprises the steps that in more than three vanadium-phosphorus-oxygen catalyst beds connected in series, the P/V molar ratio of the catalyst at the most upstream is the lowest, the P/V molar ratio of the catalyst at the middle catalyst bed is the highest, and the P/V molar ratios of the catalysts at the rest beds are gradually decreased from high to low. Except for the most upstream vanadium phosphorus oxygen catalyst bed layer, in the catalyst bed layers with the sequentially reduced P/V molar ratio of the catalyst, the P/V molar ratio in the two adjacent catalyst bed layers is sequentially reduced by 0.01-0.15 unit, preferably 0.02-0.12 unit, and most preferably 0.03-0.05 unit.
In the process of the present invention, the P/V ratio (mole) of the catalyst in each optional vanadium phosphorus oxygen catalyst bed is generally 0.93 to 1.45, preferably 0.95 to 1.25.
In the method, the mixed reaction gas of n-butane and air preferably passes through 3-5 vanadium-phosphorus oxide catalyst beds, and most preferably passes through 5 vanadium-phosphorus oxide catalyst beds. When 5 vanadium phosphorus oxygen catalyst beds are selected, according to the contact sequence with the mixed reaction gas, the catalyst with the P/V molar ratio of 0.95-0.97 is adopted in the first section, and the filling proportion is 5-15%; the second stage adopts a catalyst with a P/V molar ratio of 1.20-1.25, and the filling proportion is 10-30%; the third stage adopts a catalyst with the P/V molar ratio of 1.15-1.20, and the filling proportion is 20-30%; the fourth section adopts a catalyst with the P/V molar ratio of 1.10-1.15, and the filling proportion is 20-40%; in the fifth stage, a catalyst with the P/V molar ratio of 1.10-0.97 is adopted, and the filling proportion is 20-40%.
In the method, the vanadium element in the catalyst is quantitatively analyzed by a fluorescence method, the phosphorus element is quantitatively analyzed by a colorimetric method, and the average valence state of vanadium in the vanadium-phosphorus-oxygen catalyst is usually determined by an ammonium ferrous sulfate titration method, such as an ammonium ferrous sulfate titration method adopted by Qiaoshine (analysis laboratory, volume 17, supplement, 2008, 5 months, P222-223) and the like. The average valence of vanadium was also determined in the study of the catalyst for preparing maleic anhydride VPO by butane oxidation by ferrous ammonium sulfate titration (Hirschhorn university report, volume 14, 2 nd, 1999, month 5, P34-38).
The vanadium phosphorus oxide catalysts having different P/V molar ratios may be prepared according to conventional techniques in the art. In the process of the present invention, it is recommended to prepare vanadium phosphorus oxide catalysts having different P/V molar ratios in accordance with the requirements by the following method.
The preparation method of the vanadium phosphorus oxide catalyst provided by the invention comprises the following steps:
(1) preparing a vanadium phosphorus oxide serving as a precursor of the VPO catalyst by adopting a conventional technical means in the technical field;
(2) drying and roasting the catalyst precursor obtained in the step (1) and forming Raschig ring-shaped or cylindrical catalyst particles;
(3) and (3) keeping the catalyst formed in the step (2) at a certain temperature, and activating in a nitrogen or inert gas atmosphere or a normal butane/empty mixed gas atmosphere to obtain the activated vanadium-phosphorus-oxygen catalyst.
Wherein, in the step (1), the vanadium phosphorus oxide as a precursor of the vanadium phosphorus oxide catalyst can be prepared by the methods known in the art or conventional techniques, such as the methods disclosed in chinese patent CN103769181A or U.S. patent USP4,632,915. The preparation method of the catalyst precursor, namely the vanadium phosphorus oxide, is common knowledge in the field.
In the step (2), the forming mode can be a forming method which is conventional in the field, such as strip extrusion, sheet beating or balling.
Wherein in the step (3), the activation can be carried out under the atmosphere of one or a combination of a nitrogen/air mixed gas, a water vapor/air mixed gas or a normal butane/air mixed gas. In the present invention, it is preferable to carry out the activation treatment for the prepared catalysts having different P/V molar ratios using the same activation conditions.
In the preparation process of the catalyst precursor, catalyst precursors with different P/V molar ratios can be prepared by controlling the mass ratio of the vanadium pentoxide and the phosphoric acid added as raw materials, and the P/V ratio of the vanadium phosphorus oxygen catalyst precursor is a key factor for determining the performance of the final VPO catalyst. This is mainly because: 1. the P/V ratio affects the redox ability, and excess phosphorus largely prevents the movement of lattice oxygen, reducing the oxidation ability of the catalyst. 2. Influence on the composition of the crystalline phase of the catalyst, 4 when the phosphorus added to the catalyst is close to or exceeds (i.e. 1: 1)+The vanadium can be kept stable when being calcined at high temperature in the air to generate a large amount of (VO)2P2O7Phase, only a small fraction of VOPO4The P/V ratio is thus actually affecting the average valence of the vanadium of the catalyst. The result is that catalysts of different P/V ratios possess different average vanadium valences, oxidation capabilities, and product selectivity.
In the method of the present invention, when 5 vanadium phosphorus oxygen catalyst beds are selected, the catalyst beds may be packed by the following gradation combination method. According to the sequence of contact with the mixed reaction gas, a catalyst with a P/V molar ratio of 0.95-0.97 is adopted in the first section, the loading amount is 5-15%, a catalyst with a P/V molar ratio of 1.20-1.25 is adopted in the second section, the loading amount is 10-30%, a catalyst with a P/V molar ratio of 1.15-1.20 is adopted in the third section, the loading amount is 20-30%, a catalyst with a Vox of 1.10-1.15 is adopted in the fourth section, the loading amount is 20-40%, a catalyst with a Vox of 1.10-0.97 is adopted in the fifth section, and the loading amount is 20-40%.
In the method of the invention, the volume fraction of the n-butane in the mixed reaction gas obtained by the n-butane and the air is generally 1.2-3.0%, preferably 1.5-2.5%. The oxidation reaction conditions are as follows: the reaction pressure is normal pressure to 0.5MPa, the reaction temperature is 380 to 450 ℃, and the volume space velocity of the mixed reaction gas is 1000 to 3500h-1。
The inventors of the present application are oxidizing n-butaneWhen studying the process for the preparation of maleic anhydride, it was surprisingly found that the use of several VPO catalysts with different P/V molar ratios, the active phase (VO) of these catalysts2P2O7Phase, VOPO4The catalyst has different vanadium average valence states due to different contents of phases, the catalyst activity is obviously different, the VPO catalyst with different P/V molar ratios is adopted for grading filling, the performance of the catalyst can be regulated and controlled, reaction hot spots are effectively controlled, the product yield is improved, and the method and the result are novel and unexpected.
Therefore, compared with the prior art, the method for preparing maleic anhydride by n-butane oxidation provided by the invention has the following beneficial effects:
1. aiming at the characteristic of strong heat release of n-butane oxidation reaction, catalysts with different P/V molar ratios and different activities are adopted, the catalysts are filled in a grading manner according to the sequence that the P/V molar ratio of the catalysts is lowest and highest and then is gradually reduced from high along the direction of reactant flow, so that the balanced regulation and modulation of the activity of the catalysts are realized, and the catalytic reaction for preparing maleic anhydride by oxidizing n-butane by adopting the catalyst filling manner can quickly convert the n-butane under the working condition that the volume space velocity of reaction gas is high due to the high activity of the inlet catalyst, reduce the volume fraction of the n-butane in the raw material and avoid the phenomenon of large amount of concentrated heat release. Therefore, the method can improve the volume fraction of the n-butane in the raw materials to 1.8-3.0 percent at most. The increase of the volume fraction of the n-butane effectively improves the efficiency of the maleic anhydride production process.
2. In the process according to the invention, the feed volume fraction of n-butane is rapidly reduced at the inlet end with a high conversion in the direction of the fixed bed feed, with the attainment of a bed of lowest activity for the stability of the equilibrium reaction. Then, the reaction gas is sequentially contacted with the vanadium phosphorus oxygen catalyst with gradually increased activity, so that the concentrated and large-scale heat release in the oxidation process is effectively stabilized, and the hot spot temperature of the catalyst bed layer is reduced. In the subsequent reaction process, the activity of the catalyst is distributed in a balanced manner according to the reaction requirement, the activity of the catalyst is fully exerted, the reaction hot spot is reduced, the temperature distribution of a bed layer is even, the occurrence of side reaction can be effectively inhibited, the product selectivity is improved, and the yield of the maleic anhydride product is increased.
3. The method for quantitatively adjusting the P/V molar ratio in the catalyst is realized by controlling the raw material ratio, namely the adding amount of vanadium pentoxide and phosphoric acid, in the preparation process of the catalyst precursor, and has the advantages of simple method and reliable result, and the reaction activity of the catalyst is conveniently adjusted and controlled by controlling the P/V molar ratio.
4. The VPO catalyst has a life of about 5 years in the commercial process of maleic anhydride and the catalyst deactivation during operation is due to the loss of phosphorus from the catalyst. The oxidation of n-butane is a strongly exothermic reaction, with hot spot temperatures present, which too high promote a rapid loss of phosphorus from the catalyst. Therefore, the high temperature of the hot spot in the reaction is a key factor influencing the stability of the activity of the catalyst, and the method adopted in the invention can effectively reduce the hot spot of the reaction, thereby being beneficial to prolonging the service life of the catalyst.
5. It is generally desirable in the art to have a vanadium phosphorus oxide catalyst with better activity, i.e., a higher P/V molar ratio in the vanadium phosphorus oxide catalyst. In the present invention, it has been found through studies on the n-butane oxidation process that even for a catalyst having a high P/V molar ratio, the effect is not so desirable when only one catalyst is used; however, the catalysts with different P/V molar ratios can obtain good technical effects after being graded according to a certain sequence. Therefore, the invention provides a new process route for n-butane oxidation.
Drawings
FIG. 1 is a schematic view of the structure of a synthesis tank used in the present invention.
Fig. 2 is a XRD spectrum of the catalyst precursor. Wherein: -VOHPO4·0.5H2O。
FIG. 3 is an XRD spectrum of the catalyst products of examples 1-4 obtained after activation.
Detailed Description
The vanadium phosphorus oxide catalysts of the present invention, having different P/V molar ratios, can be prepared by the following recommended method.
(1) Synthesis of vanadium phosphorus oxide as catalyst precursor
Adding isobutanol, vanadium pentoxide and an auxiliary agent into a reaction kettle with a stirring device and a reflux condensing device through a feeding port, starting the stirring device, simultaneously heating and keeping the reaction temperature at 95-120 ℃, carrying out reflux reaction for 2-12 hours, adding concentrated phosphoric acid (with the concentration of 85% -100%), wherein the molar ratio of phosphorus to vanadium is 0.95-1.35, continuously keeping the reflux reaction for 4-8 hours, and discharging the reaction product through a reaction material outlet after the reaction is finished. The reaction mixture was cooled to room temperature and then filtered. And leaching the filter cake with a small amount of isobutanol for three times, naturally drying the filter cake for 12-24 hours at room temperature, then drying the filter cake for 8-12 hours in an oven, and finally roasting the filter cake for 4-8 hours in a muffle furnace at 200-285 ℃ to obtain a dark brown catalyst precursor, namely the nano vanadium-phosphorus oxide.
(2) Preparation of vanadium phosphorus oxide catalyst
The vanadium phosphorus oxide obtained in the step (1) is firstly molded, the prepared vanadium phosphorus oxide catalyst can be in the shapes of tablets, spheres, extruded strips and the like, and the phase of the precursor of the catalyst is (VOHPO)4·0.5H2O）。
(3) Activation treatment of vanadium phosphorus oxide catalyst
Placing the shaped catalyst into a tubular reactor, and maintaining the n-butane/air volume space velocity for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, the activation temperature is increased from room temperature to 400 ℃ for roasting treatment, the roasting treatment is carried out at 400 ℃ for 40 hours, the activation process is finished, the green vanadium-phosphorus-oxygen catalyst is obtained, and the phase of the obtained catalyst is (VO)2P2O7 phase, and a minor portion of VOPO4And (4) phase(s).
The performance of the activated vanadium phosphorus oxide catalyst can be evaluated according to the following method: the prepared vanadium phosphorus oxide catalyst is loaded into a fixed bed reactor, n-butane air mixed gas is introduced, and the composition of a reaction product is analyzed by gas chromatography. The reaction conditions were evaluated as follows: the reaction temperature is 380-450 ℃, the pressure is normal pressure-0.5 MPa,the airspeed of the n-butane mixed gas is 1000-3500 h-1And the concentration of the n-butane is 1.0 to 1.8 percent (volume percentage), and the activity evaluation test of the catalyst is carried out.
The present invention is further described in detail with reference to the following examples, which are not intended to limit the scope of the present invention, and those skilled in the art can appropriately extend the scope of the present invention in combination with the description and the entirety of the present invention.
In the examples, the detection of the crystal phase was carried out by using a D/max-2500X-ray diffractometer from RIGAKU, Japan, and the specific surface area was measured by using an AUTONORB 3B model full-automatic specific surface area and pore size analyzer from Quantachrome, USA. The vanadium element in the catalyst is quantitatively analyzed by a fluorescence method, the phosphorus element is quantitatively analyzed by a colorimetric method, and the average valence state of the vanadium in the catalyst is determined by an ammonium ferrous sulfate titration method.
Example 1
442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added into a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 47.50kg of phosphoric acid with the concentration of 85 percent is added, the molar ratio of phosphorus to vanadium is 1.27, the reflux is continuously carried out for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, naturally drying the filter cake in an enamel tray at room temperature, drying the filter cake in a drying oven at 100 ℃ for 8 hours, and finally roasting the filter cake in a muffle furnace at 250 ℃ for 5 hours to obtain a black brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, and the activation temperature is increased from room temperature to 400 ℃ for roastingKeeping the reaction solution at 400 ℃ for 40 hours, and finishing the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 21m2Per g, pore volume of 0.11cm3(ii) in terms of/g. The catalyst was analyzed by colorimetry to find the phosphorus content was 22.92%, the catalyst was analyzed by fluorometry to find the vanadium content was 30.17%, the P/V molar ratio of the catalyst was 1.25, and the average valence of the vanadium in the catalyst was + 4.01.
Example 2
442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added into a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 44.13kg of phosphoric acid with the concentration of 85 percent is added, the molar ratio of phosphorus to vanadium is 1.18, the reflux is continuously carried out for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, and finishing the reaction. And (3) naturally drying the filter cake in an enamel plate at room temperature, drying in a drying oven at 100 ℃ for 8 hours, and finally roasting in a muffle furnace at 250 ℃ for 5 hours to obtain a black-brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, heating activation temperature from room temperature to 400 ℃ for roasting treatment, keeping at 400 ℃ for 40 hours, and ending the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 27m2Per g, pore volume of 0.12cm3(ii) in terms of/g. The catalyst has a phosphorus content of 21.12% by colorimetric analysis, the catalyst has a vanadium content of 30.21% by fluorescent analysis, the P/V molar ratio of the catalyst is 1.15, and the average valence of vanadium in the catalyst is + 4.05.
Example 3
In a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, 442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 34.33kg of phosphoric acid with the concentration of 100 percent is added, the molar ratio of phosphorus to vanadium is 1.08, the reflux is continued for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, and finishing the reaction. And (3) naturally drying the filter cake in an enamel plate at room temperature, drying in a drying oven at 100 ℃ for 8 hours, and finally roasting in a muffle furnace at 250 ℃ for 5 hours to obtain a black-brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, heating activation temperature from room temperature to 400 ℃ for roasting treatment, keeping at 400 ℃ for 40 hours, and ending the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 35m2Per g, pore volume of 0.15cm3(ii) in terms of/g. The catalyst was analyzed by colorimetry to determine a phosphorus content of 19.32%, the catalyst was analyzed by fluorometry to determine a vanadium content of 30.27%, the P/V molar ratio of the catalyst was 1.05, and the average valence of the vanadium in the catalyst was + 4.10.
Example 4
In a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, 442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 31.97kg of phosphoric acid with the concentration of 100 percent is added, the molar ratio of phosphorus to vanadium is 1.0, the reflux is continued for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, and finishing the reaction. And (3) naturally drying the filter cake in an enamel plate at room temperature, drying in a drying oven at 100 ℃ for 8 hours, and finally roasting in a muffle furnace at 250 ℃ for 5 hours to obtain a black-brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, heating activation temperature from room temperature to 400 ℃ for roasting treatment, keeping at 400 ℃ for 40 hours, and ending the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 35m2Per g, pore volume of 0.15cm3(ii) in terms of/g. The catalyst was analyzed by colorimetry to show a phosphorus content of 17.89%, the catalyst was analyzed by fluorimetry to show a vanadium content of 30.34%, the P/V molar ratio of the catalyst was 0.97, and the average valence of vanadium in the catalyst was + 4.25.
Example 5
In a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, 442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 32.74kg of phosphoric acid with the concentration of 100 percent is added, the molar ratio of phosphorus to vanadium is 1.03, the reflux is continued for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, and finishing the reaction. And (3) naturally drying the filter cake in an enamel plate at room temperature, drying in a drying oven at 100 ℃ for 8 hours, and finally roasting in a muffle furnace at 250 ℃ for 5 hours to obtain a black-brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, heating activation temperature from room temperature to 400 ℃ for roasting treatment, keeping at 400 ℃ for 40 hours, and ending the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 31m2Per g, pore volume of 0.12cm3(ii) in terms of/g. The catalyst was analyzed by colorimetry to show a phosphorus content of 18.42%, the catalyst was analyzed by fluorimetry to show a vanadium content of 30.31%, the P/V molar ratio of the catalyst was 1.0, and the average valence of vanadium in the catalyst was + 4.15.
Example 6
In a reaction kettle with a stirring device and a reflux condensing device shown in figure 1, 442.95kg of isobutanol, 29.53kg of vanadium pentoxide, 0.3kg of auxiliary agent ferric nitrate hexahydrate and 0.5kg of auxiliary agent zirconium nitrate are added, stirring is started, the reaction temperature is raised and maintained at 100 +/-2 ℃, reflux reaction is carried out, the reflux time is maintained for 4 hours, 35.91kg of phosphoric acid with the concentration of 85 percent is added, the molar ratio of phosphorus to vanadium is 1.0, the reflux is continued for 8 hours, and the reaction is finished. And cooling the reaction liquid to room temperature, carrying out vacuum filtration, leaching the filter cake with a small amount of isobutanol for three times, and finishing the reaction. And (3) naturally drying the filter cake in an enamel plate at room temperature, drying in a drying oven at 100 ℃ for 8 hours, and finally roasting in a muffle furnace at 250 ℃ for 5 hours to obtain a black-brown catalyst precursor.
Adding graphite powder with the mass fraction of 4% into the prepared catalyst precursor, fully mixing, and extruding into a Raschig annular catalyst finished product by adopting a rotary tablet press and properly adjusting the impact force.
150g of the Raschig ring catalyst is put into a tubular reactor, and the n-butane/air volume space velocity is maintained for 500h under the n-butane/air atmosphere with the n-butane content of 0.6 percent (v)-1Heating rate is 2 ℃/min, heating activation temperature from room temperature to 400 ℃ for roasting treatment, keeping at 400 ℃ for 40 hours, and ending the activation process to obtain the green vanadium-phosphorus-oxygen catalyst.
The obtained catalyst has a crystalline phase (VO) detected by XRD2P2O7And beta-VOPO4Mixture of phases, specific surface area 29m2Per g, pore volume of 0.10cm3(ii) in terms of/g. The catalyst was analyzed by colorimetry to show a phosphorus content of 17.54%, the catalyst was analyzed by fluorimetry to show a vanadium content of 30.37%, the P/V molar ratio of the catalyst was 0.95, and the average valence of vanadium in the catalyst was + 4.30.
Example 7
On a 200mL test device for preparing maleic anhydride by small n-butane oxidation of a fixed bed, a stainless steel reaction tube with the inner diameter of 18mm is filled in a grading manner in three sections from bottom to top along the material flow direction, the catalyst grading scheme takes the weight of all catalysts as a reference, the first section adopts a catalyst with the P/V molar ratio of 0.97, the filling amount is 5%, the second section adopts a catalyst with the P/V molar ratio of 1.25, the filling amount is 15%, the upper part of the third section adopts a catalyst with the P/V molar ratio of 1.15, the filling amount is 25%, the middle part of the third section adopts a catalyst with the P/V molar ratio of 1.05, the filling amount is 30%, the lower part of the third section adopts a catalyst with the P/V molar ratio of 1.0, the filling amount is 25%, and the rest parts are filled with inert magnetic rings. At the reactor salt bath temperature of 420 ℃, the reaction pressure of 0.25MPa, the reaction gas is n-butane/air mixed gas with the volume concentration of 2.0 percent of the n-butane, and the gas space velocity is 1560h-1Under the reaction condition of (3), the reaction of preparing maleic anhydride from n-butane is carried out. The test results showed that the n-butane conversion was 82.2 mol% and the maleic anhydride yield was 64.7 mol%. Test results and catalyst bed Hot PointSee table 1, respectively.
Example 8
On a 200mL test device for preparing maleic anhydride by small n-butane oxidation of a fixed bed, a stainless steel reaction tube with the inner diameter of 18mm is filled in a grading manner in three sections from bottom to top along the material flow direction, the catalyst grading scheme takes the weight of all catalysts as a reference, the first section adopts a catalyst with the P/V molar ratio of 0.95, the filling amount is 5%, the second section adopts a catalyst with the P/V molar ratio of 1.2, the filling amount is 10%, the upper part of the third section adopts a catalyst with the P/V molar ratio of 1.15, the filling amount is 30%, the middle part of the third section adopts a catalyst with the P/V molar ratio of 1.05, the filling amount is 30%, the lower part of the third section adopts a catalyst with the P/V molar ratio of 1.0, the filling amount is 25%, and the rest parts are filled with inert magnetic rings. At the reactor salt bath temperature of 420 ℃, the reaction pressure of 0.25MPa, the reaction gas is n-butane/air mixed gas with the volume concentration of 2.0 percent of the n-butane, and the gas space velocity is 1560h-1Under the reaction condition of (3), the reaction of preparing maleic anhydride from n-butane is carried out. The test results showed that the n-butane conversion was 83.9% (mol) and the maleic anhydride yield was 66.2% (mol). The test results and the catalyst bed hot spots are shown in Table 1, respectively.
Comparative example 1
On a 200mL test device for preparing maleic anhydride by n-butane oxidation in a fixed bed, a reaction tube is a stainless steel reaction tube with the inner diameter of 18mm, 100mL of the catalyst prepared by the method provided by USP4,632,915 is filled, and the rest part is filled with an inert magnetic ring. At the reaction temperature of 430 ℃, the reaction pressure of 0.25MPa, the reaction gas is n-butane/air mixed gas with butane volume concentration of 1.8 percent, and the gas space velocity is 1560h-1Under the reaction condition of (3), the reaction of preparing maleic anhydride from n-butane is carried out. The test results showed that the conversion of butane was 78.1% and the molar yield of maleic anhydride was 54.5%. The test results and catalyst bed hot spots are shown in Table 1, respectively.
Comparative example 2
On a 200mL test device for preparing maleic anhydride by n-butane oxidation in a fixed bed, a stainless steel reaction tube with the inner diameter of 18mm is filled with a catalyst with the P/V molar ratio of 0.97, the filling amount is 50mL, and the rest part is filled with an inert magnetic ring. At the reactor salt bath temperature of 420 ℃, the reaction pressure of 0.25MPa, and the reaction gas is n-butane/air mixed gas with butane volume concentration of 1.6 percentThe space velocity is 1560h-1Under the reaction condition of (3), the reaction of preparing maleic anhydride from n-butane is carried out. As a result of the test, the n-butane conversion was 98.1 mol% and the maleic anhydride yield was 49.9 mol%. The test results and the catalyst bed hot spots are shown in Table 1, respectively.
Comparative example 3
On a 200mL test device for preparing maleic anhydride by n-butane oxidation in a fixed bed, a stainless steel reaction tube with the inner diameter of 18mm is filled with a catalyst with the P/V molar ratio of 1.25, the filling amount is 50mL, and the rest part is filled with an inert magnetic ring. At the reactor salt bath temperature of 420 ℃, the reaction pressure of 0.25MPa, the reaction gas is n-butane/air mixed gas with butane volume concentration of 1.6 percent, and the gas space velocity is 1560h-1Under the reaction condition of (3), the reaction of preparing maleic anhydride from n-butane is carried out. The test results showed that the n-butane conversion was 71.4 mol% and the maleic anhydride yield was 50.6 mol%. The test results and the catalyst bed hot spots are shown in Table 1, respectively.
TABLE 1 Experimental results of examples and comparative examples
N-butane conversion, mol% Yield of maleic anhydride, mol% Bed Hot Point/. degree.C
Example 7 82.2 64.7 436
Example 8 83.9 66.2 441
Comparative example 1 78.1 54.5 457
Comparative example 2 98.1 49.9 469
Comparative example 3 71.4 50.6 430

Claims (3)

1. A catalyst grading method for producing maleic anhydride by oxidizing n-butane comprises the following steps:
n-butane and air are mixed, the obtained mixed reaction gas flows through 5 vanadium-phosphorus-oxygen catalyst beds which are connected in series in a parallel flow manner, and the mixed reaction gas is contacted with a vanadium-phosphorus-oxygen catalyst to react under the condition of oxidation reaction;
according to the sequence of contact with the mixed reaction gas, a first bed layer adopts a catalyst with a P/V molar ratio of 0.95-0.97, a second bed layer adopts a catalyst with a P/V molar ratio of 1.20-1.25, a third bed layer adopts a catalyst with a P/V molar ratio of 1.15-1.20, a fourth bed layer adopts a catalyst with a P/V molar ratio of 1.10-1.15, and a fifth bed layer adopts a catalyst with a P/V molar ratio of 1.10-0.97;
the filling proportion of the first bed layer catalyst is 5-15%, the filling proportion of the second bed layer catalyst is 10-30%, the filling proportion of the third bed layer catalyst is 20-30%, the filling proportion of the fourth bed layer catalyst is 20-40%, and the filling proportion of the fifth bed layer catalyst is 20-40% by volume of all vanadium-phosphorus-oxygen catalysts.
2. The catalyst grading process according to claim 1, characterized in that the volume fraction of n-butane in the mixed reaction gas is between 1.2% and 3.0%.
3. The catalyst grading process according to claim 1, wherein the oxidation reaction conditions are: the reaction pressure is normal pressure to 0.5MPa, the reaction temperature is 380 to 450 ℃, and the volume space velocity of the mixed reaction gas is 1000 to 3500h-1。
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1068324A (en) * 1991-07-08 1993-01-27 孟山都公司 Produce the method for maleic anhydride with high yield
CN105289743A (en) * 2015-11-20 2016-02-03 西安元创化工科技股份有限公司 Vanadium phosphorus oxide catalyst for producing maleic anhydride and preparation method for catalyst

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7589217B2 (en) * 2006-04-24 2009-09-15 Sd Lizenzverwertungsgesellschaft Mbh & Co. Kg Yield improvement in the production of maleic anhydride

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1068324A (en) * 1991-07-08 1993-01-27 孟山都公司 Produce the method for maleic anhydride with high yield
CN105289743A (en) * 2015-11-20 2016-02-03 西安元创化工科技股份有限公司 Vanadium phosphorus oxide catalyst for producing maleic anhydride and preparation method for catalyst

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Fluidized Bed Reactors with Two-Zones for Maleic Anhydride Production: Different Configurations and Effect of Scale;Jorge Gascon等;《Ind. Eng. Chem. Res.》;20051101;第44卷(第24期);第8945-8951页 *
INFLUENCE OF P/V RATIO ON THE PHASE COMPOSITION AND CATALYTIC ACTIVITY OF VANADIUM PHOSPHATE BASED CATALYSTS;B.K.HODNETT等;《Applied Catalysts》;19831231;第6卷;第231-244页 *
不同P与V比的Mo/VPO催化剂物相组成及其催化性能;曾炜等;《工业催化》;20140831;第22卷(第8期);第596页左栏第1行-第598页左栏第1行 *
顺酐生产用VPO催化剂的研究进展;薛冬等;《当代化工》;20120731;第41卷(第7期);第691-693页 *

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