CN112138663B - Catalyst for preparing chloropyridine, preparation method thereof and method for preparing chloropyridine - Google Patents

Catalyst for preparing chloropyridine, preparation method thereof and method for preparing chloropyridine Download PDF

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CN112138663B
CN112138663B CN202011144524.XA CN202011144524A CN112138663B CN 112138663 B CN112138663 B CN 112138663B CN 202011144524 A CN202011144524 A CN 202011144524A CN 112138663 B CN112138663 B CN 112138663B
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chloropyridine
fecl
carrier
catalyst
preparing
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CN112138663A (en
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刘伟
高乐
常锦
陈建华
杜松松
冯旭楞
黄龙
王海星
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Beijing Fleming Technology Co ltd
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    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/74—Iron group metals
    • B01J23/745—Iron
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/80—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/889—Manganese, technetium or rhenium
    • B01J23/8892—Manganese
    • 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
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8933—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/8953—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom 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
    • C07D213/61—Halogen atoms or nitro radicals
    • 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
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/584—Recycling of catalysts

Abstract

The invention belongs to the technical field of organic synthesis, and particularly relates to a catalyst for preparing chloropyridine, a preparation method of the catalyst and a method for preparing the chloropyridine. The catalyst prepared by the preparation method has high catalytic activity for catalyzing 2-chloropyridine to prepare 2, 3-dichloropyridine and 2,3, 5-trichloropyridine, the conversion rate of the 2-chloropyridine is over 78 percent, and the total selectivity of the 2, 3-dichloropyridine and the 2,3, 5-trichloropyridine is over 64 percent. In addition, the catalyst for preparing chloropyridine provided by the invention is used for preparing 2, 3-dichloropyridine and 2,3, 5-trichloropyridine, and has the advantages of simple process, easy operation and less waste liquid, thereby being a green and environment-friendly process.

Description

Catalyst for preparing chloropyridine, preparation method thereof and method for preparing chloropyridine
Technical Field
The invention relates to the technical field of organic synthesis, in particular to a catalyst for preparing chloropyridine, a preparation method thereof and a method for preparing chloropyridine.
Background
2, 3-dichloropyridine and 2,3, 5-trichloropyridine are important fine chemical intermediates and are widely applied to the research fields of medicines and pesticides.
The existing method for producing 2, 3-dichloropyridine mainly comprises the steps of taking nicotinamide as an initial raw material, preparing 3-aminopyridine by carrying out Hofmann amide degradation, carrying out chlorination reaction on the 3-aminopyridine in a mixed solution of concentrated hydrochloric acid and hydrogen peroxide to generate 2-chloro-3-aminopyridine, and finally carrying out diazotization reaction to prepare the 2, 3-dichloropyridine. The process has the disadvantages of complicated steps and high cost. In recent years, the prior art (for example, CN105418492A, CN103145609A) discloses a method for preparing 2, 3-dichloropyridine by catalytic reduction of 2,3, 6-trichloropyridine using 2,3, 6-trichloropyridine as a raw material and heavy metals of palladium, platinum, raney nickel or raney copper as a catalyst using a reducing agent such as hydrogen, however, in the process of preparing 2, 3-dichloropyridine, the catalyst is extremely easy to be poisoned and inactivated, and the conversion rate of 2,3, 6-trichloropyridine and the selectivity of 2, 3-dichloropyridine are low.
The synthesis of 2,3, 5-trichloropyridine mainly comprises the following three methods: (1) pyridine is directly chlorinated in a gas phase or a liquid phase, the yield of the method is not high, the reaction is carried out under high pressure, and the requirement on equipment is harsh; (2) 2,3,4, 5-tetrachloropyridine and pentachloropyridine are reduced by zinc powder, so that the method has high production cost and generates a large amount of wastewater; (3) in the presence of a catalyst, trichloroacetaldehyde and acrylonitrile are subjected to addition reaction to generate 2,4, 4-dichloro-4-formylbutyronitrile, then the ring-closing reaction is continuously performed, and one molecule of water is removed to obtain the 2,3, 5-trichloropyridine.
Disclosure of Invention
The catalyst obtained by the preparation method for preparing the chloropyridine has higher catalytic activity for catalyzing 2-chloropyridine to prepare 2, 3-dichloropyridine and 2,3, 5-trichloropyridine, and the process for preparing the 2, 3-dichloropyridine and the 2,3, 5-trichloropyridine is simple, easy to implement and free of pollution to the environment.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a preparation method of a catalyst for preparing chloropyridine, which comprises the following steps:
soaking a carrier in an aqueous solution of an active ingredient precursor compound, and then drying and roasting the carrier in sequence to obtain a catalyst for preparing chloropyridine;
the carrier is at least one of gear alumina, activated carbon, molecular sieve and silicon dioxide;
the active ingredient precursor compound is FeCl3、CuCl2、CoCl2、ZnCl2、FeCl2、MnCl2、LaCl3、NiCl2、BiCl3、RuCl3And H2PtCl6At least one of;
the roasting temperature is 300-550 ℃, and the roasting time is 1-12 hours; when the carrier contains activated carbon, the roasting is carried out in a protective atmosphere, and when the carrier does not contain activated carbon, the roasting is carried out in a protective atmosphere or an air atmosphere.
Preferably, the impregnation is room-temperature impregnation, and the time of the room-temperature impregnation is 5-24 hours.
Preferably, the dipping is carried out for 3-10 h at the temperature of 40-80 ℃.
Preferably, the mass concentration of the aqueous solution of the active ingredient precursor compound is 0.1-50%; the impregnation adopts an equal-volume impregnation method or excess impregnation.
Preferably, the carrier is impregnated after being purified, and when the carrier is activated carbon, the purification treatment comprises acid leaching and water washing; and when the carrier is other than active carbon, the purification treatment is water washing.
Preferably, the acid leaching solution used for acid leaching is a nitric acid solution with the mass concentration of 8-12%, the acid leaching temperature is 65-75 ℃, and the acid leaching time is 4-6 hours.
The invention also provides a catalyst for preparing chloropyridine, which is obtained by the preparation method in the technical scheme, wherein the chloropyridine comprises 2, 3-dichloropyridine and 2,3, 5-trichloropyridine.
The invention also provides a method for preparing chloropyridine, which comprises the following steps:
mixing vaporized 2-chloropyridine with chlorine, and carrying out chlorination reaction under the action of a catalyst to obtain 2, 3-dichloropyridine and 2,3, 5-trichloropyridine; the catalyst is the catalyst for preparing chloropyridine in the technical scheme; the molar ratio of the 2-chloropyridine to the chlorine is 1: 2-5.
Preferably, the temperature of the chlorination reaction is 150-400 ℃, the pressure is 0.1-0.5 MPa, and the airspeed is 180-300 h-1。
Preferably, the chlorination reaction is carried out in a fixed bed reactor or a fluidized bed reactor.
The catalyst prepared by the preparation method has high catalytic activity for catalyzing 2-chloropyridine to prepare 2, 3-dichloropyridine and 2,3, 5-trichloropyridine, the conversion rate of the 2-chloropyridine is over 78 percent, and the total selectivity of the 2, 3-dichloropyridine and the 2,3, 5-trichloropyridine is over 64 percent. In addition, the catalyst for preparing chloropyridine provided by the invention is used for preparing 2, 3-dichloropyridine and 2,3, 5-trichloropyridine, and has the advantages of simple process, easy operation and less waste liquid, thereby being a green and environment-friendly process.
Detailed Description
The invention provides a preparation method of a catalyst for preparing chloropyridine, which comprises the following steps:
soaking a carrier in an aqueous solution of an active ingredient precursor compound, and then drying and roasting the carrier in sequence to obtain a catalyst for preparing chloropyridine;
the carrier is at least one of gear alumina, activated carbon, molecular sieve and silicon dioxide;
the active ingredient precursor compound is FeCl3、CuCl2、CoCl2、ZnCl2、FeCl2、MnCl2、LaCl3、NiCl2、BiCl3、RuCl3And H2PtCl6At least one of (a);
the roasting temperature is 300-550 ℃, and the roasting time is 1-12 hours; when the carrier contains activated carbon, the roasting is carried out in a protective atmosphere, and when the carrier does not contain activated carbon, the roasting is carried out in a protective atmosphere or an air atmosphere.
The preparation method of the catalyst for preparing chloropyridine provided by the invention is preferably a preparation method of the catalyst for preparing 2, 3-dichloropyridine and 2,3, 5-trichloropyridine.
The invention provides for the impregnation of a carrier in an aqueous solution of an active ingredient precursor compound.
In the invention, the carrier is at least one of gear alumina, activated carbon, molecular sieve and silica, preferably gear alumina, activated carbon, molecular sieve or silica, and more preferably gear alumina or activated carbon. The source of the carrier is not particularly limited, and any commercially available product can be adopted, for example, the coconut shell activated carbon in the embodiment of the invention is coconut shell activated carbon (specification model: HPZ-03R, product batch: H190626002) of Fujian Xinsen carbon industries, Inc., and the columnar activated carbon is columnar activated carbon (specification model: Cl-30, product batch: H190626001) of Fujian Xinsen carbon industries, Inc.
In the present invention, the active ingredient precursor compound is FeCl3、CuCl2、CoCl2、ZnCl2、FeCl2、MnCl2、LaCl3、NiCl2、BiCl3、RuCl3And H2PtCl6Preferably FeCl3、CuCl2、CoCl2、ZnCl2、FeCl2、MnCl2、LaCl3And H2PtCl6At least one of; when the active ingredient precursor compound is a combination of the above, the ratio of each substance in the present invention is not particularly limited. In the embodiment of the present invention, FeCl may be particularly preferable3And FeCl2The FeCl3And FeCl2The mass ratio of (A) to (B) is preferably 1: 1.5-1.6, and more preferably 1: 1.55; more specifically, FeCl is preferable2、CoCl2And ZnCl2In which FeCl2、CoCl2And ZnCl2Is preferably in a mass ratio of11.3-11.4: 11-11.2: 21.3-21.5, more preferably 11.36:11.14: 21.4; more specifically, FeCl is preferable3Or FeCl2(ii) a FeCl is particularly preferred2、MnCl2And ZnCl2In which FeCl2、MnCl2And ZnCl2The mass ratio of (A) to (B) is preferably 11.3-11.4: 11.5-11.6: 21.3-21.5, more preferably 11.36:11.57: 21.4; FeCl is particularly preferred2、CoCl2And LaCl3In which FeCl2、CoCl2And LaCl3The mass ratio of (A) to (B) is preferably 22.7-22.8: 11.1-11.2: 5.2-5.4, and more preferably 22.71:11.14: 5.3; more specifically, H is preferable2PtCl6、CuCl2And ZnCl2The combined active ingredient precursor compounds of (1), wherein H2PtCl6、CuCl2And ZnCl2The mass ratio of (A) to (B) is preferably 0.4 to 0.5:9.8 to 9.9:21.4, more preferably 0.4:9.84: 21.4.
In the present invention, the mass concentration of the aqueous solution of the active ingredient precursor compound is preferably 0.1 to 50%, more preferably 8.2 to 49%, and particularly preferably 8.2%, 11.8%, 17.2%, 18.4%, 20.9%, 23.3%, or 49%; when the active ingredient precursor compound includes a plurality of substances, the mass concentration of the aqueous solution of the active ingredient precursor compound refers to the total concentration of all the active ingredient precursor compounds; the impregnation is preferably equal-volume impregnation or excess impregnation, and when the impregnation is excess impregnation, the amount of the aqueous solution of the active ingredient precursor compound is preferably 2-5 times the volume of the aqueous solution of the active ingredient precursor compound required for equal-volume impregnation.
According to the invention, the carrier is preferably subjected to purification treatment and then impregnated; when the carrier is activated carbon, the purification treatment preferably comprises acid leaching and water washing; the acid leaching solution for acid leaching is preferably a nitric acid solution with the mass concentration of 8-12%, and more preferably a nitric acid solution with the mass concentration of 10%; the acid leaching temperature is preferably 65-75 ℃, and more preferably 70 ℃; the acid leaching time is preferably 4-6 h, and more preferably 5 h; the washing mode is not particularly limited, the activated carbon can be washed to be neutral, and the washing water is preferably deionized water; after the purification treatment is finished, the activated carbon obtained by the purification treatment is preferably dried and then used for impregnation, the drying mode and parameters are not particularly limited, and a constant-weight product can be obtained, wherein in the embodiment of the invention, the drying temperature is preferably 100-120 ℃, and more preferably 110 ℃. In the invention, when the carrier is activated carbon, the activated carbon is subjected to acid leaching, so that ash content in the activated carbon can be reduced, and the surface oxygen content of the activated carbon can be increased.
In the present invention, when the carrier is other than activated carbon, the purification treatment is preferably water washing; the washing can realize the cleaning of the pore passages of the carrier and reduce impurities; the washing mode is not particularly limited, and the carrier can be washed cleanly by water; the water for washing is preferably deionized water. After the water washing is finished, the carrier after the water washing is preferably dried and then used for impregnation, the drying mode and parameters are not particularly limited, a constant weight product can be obtained, and in the embodiment of the invention, the drying temperature is preferably 110 ℃.
The impregnation conditions are not particularly limited, and the active ingredient precursor compound can be loaded on the carrier, in the embodiment of the invention, the impregnation is preferably room-temperature impregnation (i.e. impregnation is carried out under the condition of no additional heating or cooling), and the time of the room-temperature impregnation is preferably 5-24 h; the dipping is preferably carried out for 3-10 h at 40-80 ℃, the dipping temperature can be changed within the range of 40-80 ℃ in the dipping process at 40-80 ℃, the influence on the dipping effect is not large, for example, after the dipping is carried out for 4h at 70 ℃, the temperature is increased to 80 ℃ and then the dipping is carried out for 1 h.
After the impregnation is finished, the carrier obtained by impregnation is dried to obtain the dried carrier loaded with the active ingredient precursor.
The drying temperature of the impregnated carrier is not particularly limited, and a product with constant weight can be obtained, and in the embodiment of the invention, the drying temperature of the impregnated carrier is preferably 100-120 ℃, and more preferably 110 ℃.
After obtaining the dry carrier loaded with the active ingredient precursor, the invention bakes the dry carrier loaded with the active ingredient precursor to obtain the catalyst for preparing chloropyridine.
In the invention, the roasting temperature is 300-550 ℃, preferably 350-500 ℃, and particularly preferably 350, 400, 450 or 500 ℃; the roasting time is 1-12 hours, preferably 3-5 hours; when the carrier contains activated carbon, the roasting is carried out in a protective atmosphere, and when the carrier does not contain activated carbon, the roasting is carried out in a protective atmosphere or an air atmosphere. In the present invention, the protective atmosphere is preferably a nitrogen atmosphere. The activated carbon is roasted under the protective atmosphere, so that the oxidation loss of the activated carbon can be avoided.
The invention also provides a catalyst for preparing chloropyridine, which is obtained by the preparation method in the technical scheme, wherein the chloropyridine comprises 2, 3-dichloropyridine and 2,3, 5-trichloropyridine.
The invention also provides a method for preparing chloropyridine, which is characterized by comprising the following steps:
mixing vaporized 2-chloropyridine with chlorine, and carrying out chlorination reaction under the action of a catalyst to obtain 2, 3-dichloropyridine and 2,3, 5-trichloropyridine; the catalyst is the catalyst for preparing chloropyridine in the technical scheme; the molar ratio of the 2-chloropyridine to the chlorine is 1: 2-5.
In the invention, the mole ratio of the 2-chloropyridine to the chlorine is preferably 1: 3-5.
In the invention, the temperature of the vaporized 2-chloropyridine is preferably 170-190 ℃, and more preferably 180 ℃; the vaporization is preferably carried out in a vaporizer.
In the present invention, the mixing of the vaporized 2-chloropyridine and chlorine is preferably carried out in a mixer; particularly preferably, vaporized 2-chloropyridine is substituted into a mixer by using protective gas to be mixed with chlorine; the protective gas is preferably nitrogen or argon; the volume ratio of the shielding gas to the 2-chloropyridine (in a liquid state) is preferably 1-2500: 1, more preferably 1500-2500: 1, particularly preferably 1500:1, 2000:1 or 2500:1, and the pressure of the shielding gas is preferably 0.5-2 MPa, particularly preferably 0.5MPa, 1MPa, 1.5MPa or 2 MPa. In the present invention, the mode of introducing the vaporized 2-chloropyridine into the mixer by the shielding gas is not particularly limited, and in the embodiment of the present invention, it is preferable that the shielding gas and the 2-chloropyridine are introduced into the vaporizer in a ratio, and then the shielding gas and the vaporized 2-chloropyridine are discharged from the vaporizer and supplied to the mixer.
In the invention, the temperature of the chlorination reaction is preferably 150-400 ℃, more preferably 280-400 ℃, and particularly preferably 280, 320 or 400 ℃; the pressure of the chlorination reaction is preferably 0.1-0.5 MPa, particularly preferably 0.1, 0.3 or 0.5MPa, and the space velocity of the chlorination reaction is preferably 180-300 h-1More preferably 180, 240 or 300h-1。
In the present invention, the chlorination reaction is preferably carried out in a fixed bed reactor or a fluidized bed reactor.
The catalyst for preparing chloropyridine and the preparation method thereof and the method for preparing chloropyridine provided by the present invention are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention.
Example 1
Placing the coconut shell activated carbon in 10 wt.% nitric acid solution, soaking for 5h at 70 ℃, then washing to neutrality by using deionized water, and then drying to constant weight at 110 ℃ to obtain the purified coconut shell activated carbon;
71.22g of FeCl2·4H2O and 48.75g FeCl3·6H2Dissolving O in 200mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is 2.5 times that of the active ingredient precursor compound aqueous solution for isovolumetrically impregnating the purified coconut shell activated carbon of 100 g; adding 100g of purified coconut shell activated carbon into the active ingredient precursor compound aqueous solution under stirring, heating to 70 ℃, soaking at 70 ℃ for 5h, filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain the loaded active ingredientCoconut shell activated carbon of the precursor compound; roasting the coconut shell activated carbon loaded with the active component precursor compound for 3 hours at 350 ℃ in a nitrogen atmosphere to obtain a catalyst for preparing chloropyridine, which is marked as a No. 1 catalyst;
loading a No. 1 catalyst into a fixed bed reactor, introducing nitrogen and 2-chloropyridine liquid with the pressure of 0.5MPa into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 2500:1 for vaporization, mixing a mixed gas discharged by the vaporizer and chlorine according to the molar ratio of 2-chloropyridine to chlorine of 1:5, and reacting for 300h-1The space velocity of the reaction is introduced into a fixed bed reactor, chlorination reaction is carried out under the conditions of 320 ℃ and 0.1MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of 2-chloropyridine is 96.8 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine is 85.1 percent, wherein the selection behavior of 2, 3-dichloropyridine is 26 percent, and the selectivity of 2,3, 5-trichloropyridine is 59.1 percent.
Example 2
Repeatedly stirring and cleaning gear alumina in deionized water until no white dust exists in the cleaned solution, then filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain purified gear alumina;
53.41g of FeCl were weighed2·4H2Dissolving O in 360mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is 3 times that of 150g of purified gear aluminum oxide which is isovolumetrically dipped in the required active ingredient precursor compound aqueous solution; adding 150g of purified gear alumina into the active ingredient precursor compound aqueous solution in a stirring state, soaking at room temperature for 5h, filtering, drying the obtained solid at 110 ℃ for 6h to obtain gear alumina loaded with the active ingredient precursor compound, and then roasting the gear alumina loaded with the active ingredient precursor compound at 400 ℃ for 5h to obtain a catalyst for preparing chloropyridine, which is marked as a No. 2 catalyst;
loading the No. 2 catalyst into a fluidized bed reactor, introducing nitrogen with the pressure of 1.5MPa and 2-chloropyridine liquid into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 1500:1 for vaporization, and vaporizingMixing the mixed gas discharged from the gasifier with chlorine according to the molar ratio of 2-chloropyridine to chlorine of 1:4 for 240h-1The space velocity of the reaction is introduced into a fixed bed reactor, chlorination reaction is carried out under the conditions of 280 ℃ and 0.5MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of 2-chloropyridine is 78 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine reaches 73.1 percent, wherein the selectivity of 2, 3-dichloropyridine is 33 percent, and the selectivity of 2,3, 5-trichloropyridine is 40.1 percent.
Example 3
Repeatedly stirring and cleaning gear alumina in deionized water until no white dust exists in the cleaned solution, then filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain purified gear alumina;
17.81g of FeCl2·4H2O, 20.4g of CoCl2·6H2O and 21.4g ZnCl2Dissolving in 150mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is 2 times of that of the active ingredient precursor compound aqueous solution for soaking 100g of purified gear aluminum oxide in equal volume; adding 100g of purified gear aluminum oxide into the active component precursor compound aqueous solution in a stirring state, then heating to 70 ℃, soaking for 4h at 70 ℃, heating to 80 ℃, and soaking for 1h at 80 ℃ to finish the soaking; filtering the material obtained after impregnation, and drying the solid obtained by filtering at 110 ℃ for 6h to obtain gear alumina loaded with an active ingredient precursor compound; roasting the gear alumina loaded with the precursor compound of the active ingredient at 500 ℃ for 5 hours to obtain a catalyst for preparing chloropyridine, which is marked as a No. 3 catalyst;
loading a No. 3 catalyst into a fluidized bed reactor, introducing nitrogen and 2-chloropyridine liquid with the pressure of 1MPa into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 2000:1 for vaporization, mixing mixed gas discharged by the vaporizer and chlorine according to the molar ratio of 1:3 of 2-chloropyridine to chlorine, and mixing for 240h-1Introducing into a fixed bed reactor, performing chlorination reaction at 400 deg.C and 0.3MPa, collecting the product, and performing gas chromatographyThe product composition is measured by an area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of the 2-chloropyridine is 85 percent, and the total selectivity of the 2, 3-dichloropyridine and the 2,3, 5-trichloropyridine reaches 95 percent, wherein the selectivity of the 2, 3-dichloropyridine is 39 percent, and the selectivity of the 2,3, 5-trichloropyridine is 56 percent.
Example 4
Putting the columnar activated carbon into 10 wt.% nitric acid solution, soaking for 5h at 70 ℃, then washing to neutrality by using deionized water, and drying to constant weight at 110 ℃ to obtain purified columnar activated carbon;
48.75g of FeCl3·6H2Dissolving O in 200mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is 2.5 times that of the active ingredient precursor compound aqueous solution required by isovolumic impregnation of 100g of purified columnar activated carbon; adding 100g of purified columnar activated carbon into the active component precursor compound aqueous solution in a stirring state, then heating to 70 ℃, soaking for 5h at 70 ℃, and filtering to obtain coconut shell activated carbon loaded with the active component precursor compound; roasting the coconut shell activated carbon loaded with the active component precursor compound for 3 hours at 450 ℃ in a nitrogen atmosphere to obtain a catalyst for preparing chloropyridine, which is marked as a No. 4 catalyst;
loading a No. 4 catalyst into a fixed bed reactor, introducing nitrogen and 2-chloropyridine liquid with the pressure of 1MPa into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 1500:1 for vaporization, mixing a mixed gas discharged by the vaporizer and chlorine according to the molar ratio of 1:5 of 2-chloropyridine to chlorine, and reacting for 180h-1The space velocity of the reaction is introduced into a fixed bed reactor, chlorination reaction is carried out under the conditions of 400 ℃ and 0.1MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of 2-chloropyridine is 100 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine reaches 64 percent, wherein the selectivity of 2, 3-dichloropyridine is 30 percent, and the selectivity of 2,3, 5-trichloropyridine is 34 percent.
Example 5
Placing the coconut shell activated carbon in 12 wt.% nitric acid solution, soaking for 6h at 75 ℃, then washing to neutrality by using deionized water, and then drying to constant weight at 110 ℃ to obtain the purified coconut shell activated carbon;
17.81g of FeCl2·4H2O and 18.19g of MnCl2·4H2O, 21.4g ZnCl2Dissolving in 200mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is 2.5 times of that of the active ingredient precursor compound aqueous solution for isovolumetrically impregnating the purified coconut shell activated carbon of 100 g; adding 100g of purified coconut shell activated carbon into the active ingredient precursor compound aqueous solution in a stirring state, then heating to 70 ℃, soaking for 5h at 70 ℃, filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain the coconut shell activated carbon loaded with the active ingredient precursor compound; roasting the coconut shell activated carbon loaded with the active component precursor compound for 5 hours at 350 ℃ in a nitrogen atmosphere to obtain a catalyst for preparing chloropyridine, which is marked as a No. 5 catalyst;
charging No. 5 catalyst into a fluidized bed reactor, vaporizing nitrogen and 2-chloropyridine liquid at a volume ratio of 2500:1 by a vaporizer at a temperature of 180 ℃, mixing a mixed gas discharged from the vaporizer and chlorine gas according to a molar ratio of 2-chloropyridine to chlorine gas of 1:4, and reacting for 300h-1The space velocity of the catalyst is introduced into a fixed bed reactor, chlorination reaction is carried out at 280 ℃ and 0.5MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the selectivity of the products are further calculated, so that the conversion rate of 2-chloropyridine is 97.2 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine reaches 66 percent, wherein the selectivity of the 2, 3-dichloropyridine is 32.5 percent, and the selectivity of the 2,3, 5-trichloropyridine is 33.5 percent.
Example 6
Putting gear alumina into deionized water, stirring and cleaning, then filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain purified gear alumina;
35.61g of FeCl2·4H2O, 20.4g of CoCl2·6H2O and 6.5g of LaCl3·7H2Dissolving O in 150mL deionized water to obtain active ingredient precursor compoundAn aqueous solution having a volume of 2 times that of an aqueous solution of the precursor compound of the desired active ingredient impregnated with 100g of the purified gear alumina in an equal volume; adding 100g of purified gear aluminum oxide into the active component precursor compound aqueous solution in a stirring state, then heating to 70 ℃, and soaking at 70 ℃ for 5 hours to finish the soaking; filtering the material obtained after impregnation, and drying the solid obtained by filtering at 110 ℃ for 6h to obtain gear alumina loaded with an active ingredient precursor compound; roasting the gear alumina loaded with the active ingredient precursor compound for 3 hours at 450 ℃ in an air atmosphere to obtain a catalyst for preparing chloropyridine, which is marked as a No. 6 catalyst;
loading a No. 6 catalyst into a fixed bed reactor, introducing nitrogen and 2-chloropyridine liquid with the pressure of 1MPa into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 2000:1 for vaporization, mixing a mixed gas discharged by the vaporizer and chlorine according to the molar ratio of 1:5 of 2-chloropyridine to chlorine, and reacting for 240h-1The space velocity of the reaction is introduced into a fixed bed reactor, chlorination reaction is carried out under the conditions of 280 ℃ and 0.3MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of 2-chloropyridine is 76.8 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine reaches 81.3 percent, wherein the selectivity of 2, 3-dichloropyridine is 32.1 percent, and the selectivity of 2,3, 5-trichloropyridine is 49.2 percent.
Example 7
Placing the coconut shell activated carbon in 10 wt.% nitric acid solution, soaking for 5h at 70 ℃, then washing to neutrality by using deionized water, and then drying to constant weight at 110 ℃ to obtain the purified coconut shell activated carbon;
0.5g of H2PtCl6·6H2O and 11.92g of CuCl2·2H2O, 21.4g ZnCl2Dissolving the solution in 35mL of deionized water to obtain an active ingredient precursor compound aqueous solution, wherein the volume of the active ingredient precursor compound aqueous solution is the same as that of an active ingredient precursor compound aqueous solution required by isovolumic impregnation of 44g of purified coconut shell activated carbon; adding 44g purified coconut shell activated carbon into the active ingredient precursor compound water solution under stirring, and soaking at room temperatureAfter 5h, filtering, and drying the obtained solid at 110 ℃ to constant weight to obtain coconut shell activated carbon loaded with an active ingredient precursor compound; roasting the coconut shell activated carbon loaded with the active component precursor compound for 5 hours at 350 ℃ in a nitrogen atmosphere to obtain a catalyst for preparing chloropyridine, which is marked as 7 catalyst;
loading a No. 7 catalyst into a fluidized bed reactor, introducing nitrogen and 2-chloropyridine liquid with the pressure of 2MPa into a vaporizer with the temperature of 180 ℃ according to the volume ratio of 2500:1 for vaporization, mixing mixed gas discharged by the vaporizer and chlorine according to the molar ratio of 1:3 of 2-chloropyridine to chlorine, and mixing for 240h-1The space velocity of the reaction is introduced into a fixed bed reactor, chlorination reaction is carried out under the conditions of 280 ℃ and 0.5MPa, products are collected, the composition of the products is measured by adopting a gas chromatography area normalization method, and the conversion rate and the product selectivity are further calculated, so that the conversion rate of 2-chloropyridine is 78.4 percent, the total selectivity of 2, 3-dichloropyridine and 2,3, 5-trichloropyridine reaches 68.5 percent, wherein the selectivity of 2, 3-dichloropyridine is 33.8 percent, and the selectivity of 2,3, 5-trichloropyridine is 34.7 percent.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and amendments can be made without departing from the principle of the present invention, and these modifications and amendments should also be considered as the protection scope of the present invention.

Claims (9)

1. A process for preparing chloropyridines comprising the steps of:
mixing vaporized 2-chloropyridine with chlorine, and carrying out chlorination reaction under the action of a catalyst to obtain 2, 3-dichloropyridine and 2,3, 5-trichloropyridine;
the mol ratio of the 2-chloropyridine to the chlorine is 1: 2-5;
the preparation method of the catalyst comprises the following steps:
soaking a carrier in an aqueous solution of an active ingredient precursor compound, and then drying and roasting the carrier in sequence to obtain a catalyst for preparing chloropyridine;
the carrier is at least one of gear alumina, activated carbon, molecular sieve and silicon dioxide;
the active ingredient precursor compound is FeCl3And FeCl2Of FeCl2、CoCl2And ZnCl2Of FeCl2、CoCl2And LaCl3The composition of (1);
the FeCl3And FeCl2In a composition of3And FeCl2The mass ratio of (1): 1.5 to 1.6;
the FeCl2、CoCl2And ZnCl2In a composition of2、CoCl2And ZnCl2The mass ratio of (A) to (B) is 11.3-11.4: 11-11.2: 21.3 to 21.5;
the FeCl2、CoCl2And LaCl3In a composition of2、CoCl2And LaCl3The mass ratio of (A) to (B) is 22.7-22.8: 11.1-11.2: 5.2 to 5.4;
the roasting temperature is 300-550 ℃, and the roasting time is 1-12 hours; when the carrier contains activated carbon, the roasting is carried out in a protective atmosphere, and when the carrier does not contain activated carbon, the roasting is carried out in a protective atmosphere or an air atmosphere.
2. The method according to claim 1, wherein the impregnation is room-temperature impregnation, and the time of the room-temperature impregnation is 5-24 hours.
3. The method according to claim 1, wherein the impregnation is carried out at 40-80 ℃ for 3-10 h.
4. The method according to any one of claims 1 to 3, wherein the mass concentration of the aqueous solution of the active ingredient precursor compound is 0.1 to 50%; the impregnation adopts an equal volume impregnation method or excess impregnation.
5. The method according to claim 1, wherein the carrier is purified and then impregnated, and when the carrier is activated carbon, the purification comprises acid leaching and water washing; and when the carrier is other than active carbon, the purification treatment is water washing.
6. The method of claim 5, wherein the acid leaching solution used for acid leaching is a nitric acid solution with a mass concentration of 8-12%, the acid leaching temperature is 65-75 ℃, and the acid leaching time is 4-6 h.
7. The method of claim 1, wherein the chloropyridines include 2, 3-dichloropyridine and 2,3, 5-trichloropyridine.
8. The method of claim 1, wherein the temperature of the chlorination reaction is 150-400 ℃, the pressure is 0.1-0.5 MPa, and the space velocity is 180-300 h-1。
9. The process according to claim 1 or 8, characterized in that the chlorination reaction is carried out in a fixed bed reactor or a fluidized bed reactor.
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IL78341A (en) * 1986-03-31 1989-08-15 Makhteshim Chem Works Ltd Method of preparing 2,3,6-trichloropyridine and 2,3,5,6-tetrachloropyridine in the gas phase
CN1657164A (en) * 2004-12-22 2005-08-24 东南大学 Catalyst for preparing penta chloropyridine and its preparation method
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CN105642280B (en) * 2016-03-17 2018-07-31 西安凯立新材料股份有限公司 Continuous production 2,3- dichloropyridine catalyst and its preparation method and application
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