CN115957811A - In-situ regeneration method of liquid phase Beckmann rearrangement catalyst - Google Patents

In-situ regeneration method of liquid phase Beckmann rearrangement catalyst Download PDF

Info

Publication number
CN115957811A
CN115957811A CN202310039709.1A CN202310039709A CN115957811A CN 115957811 A CN115957811 A CN 115957811A CN 202310039709 A CN202310039709 A CN 202310039709A CN 115957811 A CN115957811 A CN 115957811A
Authority
CN
China
Prior art keywords
cleaning
catalyst
acid
beckmann rearrangement
solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310039709.1A
Other languages
Chinese (zh)
Inventor
庄大为
杨琦武
刘新伟
王聪
杨克俭
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Tianchen Engineering Corp
Original Assignee
China Tianchen Engineering Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Tianchen Engineering Corp filed Critical China Tianchen Engineering Corp
Priority to CN202310039709.1A priority Critical patent/CN115957811A/en
Publication of CN115957811A publication Critical patent/CN115957811A/en
Pending legal-status Critical Current

Links

Classifications

    • 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

Landscapes

  • Catalysts (AREA)

Abstract

The invention provides an in-situ regeneration method of a liquid phase Beckmann rearrangement catalyst, wherein an inactivated catalyst is a molecular sieve supported catalyst and comes from a liquid phase Beckmann rearrangement reaction, and the regeneration method comprises the following steps: (1) introducing a cleaning solution A into a reaction tube filled with a catalyst; (2) introducing the cleaning liquid B into a reaction tube filled with a catalyst; (3) Heating a reaction tube filled with a catalyst, and introducing gas; and (4) introducing the regenerated liquid into a reaction tube filled with the catalyst. According to the in-situ regeneration method of the liquid-phase Beckmann rearrangement catalyst, the catalyst regeneration scheme provided by the method can completely recover the activity of the catalyst, has the advantages of obvious method effect, no need of unloading, low cost, small pollution and the like, and is suitable for catalyst treatment in caprolactam industrial production.

Description

In-situ regeneration method of liquid phase Beckmann rearrangement catalyst
Technical Field
The invention belongs to the technical field of chemical synthesis, and particularly relates to an in-situ regeneration method of a liquid phase Beckmann rearrangement reaction catalyst.
Background
Caprolactam is an important organic chemical raw material, and is mainly used as a monomer of a high polymer to generate polyamide 6 (PA 6) slices through polymerization due to the special structure of the caprolactam. The caprolactam material can be used for producing nylon plastics, cotton fiber, artificial leather and other related products, has very obvious application effect in various medical fields, and can be used for producing antiplatelet and other related medicaments. PA6 slices of different brands have different performances and different application fields, and the processed and molded PA6 is widely applied to the fields of textiles, packaging, automobiles, electronics, machinery and the like.
The world caprolactam production raw material route is mainly benzene, phenol and toluene. The toluene path in the three raw materials has the highest capacity, and is the world's most important caprolactam production method. Has been represented by the technology of DSM company in the Netherlands, cyclohexanone oxime is synthesized by preparing cyclohexanone, and caprolactam is obtained by Beckmann rearrangement. In recent years, the caprolactam production technology in China is greatly improved, and the domestic productivity is greatly expanded.
The change of caprolactam production capacity in China shows a steady growth trend, the growth rate is 81.8 percent from 2250kt/a in 2015 to 4090kt/a in 2019, the average annual growth rate is 16.11 percent, and the average annual growth rate far exceeds the average annual growth rate in the world. Domestic caprolactam production enterprises are mainly distributed in the east coastal region, wherein the productive capacity reaches 400kt/a, such as Fujian Shenyuan New Material Co., fubang special Oriental chemical Co., ltd, haili chemical Co., ltd, zhejiang Balng Hengyi caprolactam Co., ltd. From the published energy expansion plan, the caprolactam industry will be increased in a new round in 2020-2025, which includes 40kt/a energy expansion project of orchid science and technology creation corporation, 200kt/a energy expansion project of Fujian Shenyuan New Material Co., ltd, 200kt/a energy expansion project of Pingtao Shenma group, 200kt/a new project of Nei Mongolia Qing group Co., ltd, 200kt/a energy expansion project of Fujian Yongrong group, 600kt/a moving project of Chinese petrochemical Barring petrochemical company, etc., and the domestic caprolactam production capacity will exceed 5200kt/a by the end of 2025, so that the market competition will be further intensified.
The Beckmann rearrangement (Beckmann rearrangement) is a rearrangement reaction catalyzed by an acid, and oxime as a reactant is rearranged into an amide under the catalysis of the acid. Various beckmann rearrangement catalysts are available, including inorganic acids, organic acids, acidic molecular sieves, ionic liquids, and the like. These catalyst schemes have been studied in detail.
Compared with the existing liquid phase rearrangement, the technology can not use ammonia gas, greatly saves the production cost of caprolactam, and is an important scheme for the development of the caprolactam rearrangement process. Molecular sieve catalysts such as ZSM-5, S-1 and the like are more researched catalysts in the Beckmann rearrangement reaction.
Takahashi et al studied the deactivation behavior of HZSM-5 molecular sieves with different silica-alumina ratios in the gas phase Beckmann rearrangement reaction. Research shows that when the number of strong acid centers is too large, the conversion rate is high, but the selectivity is low and can only reach 46 percent; when the amount is too small, the conversion of cyclohexanone oxime and the selectivity of caprolactam are both low. In addition, the smaller the number of strong acid sites and the smaller the pore size, the slower the catalyst deactivation. Ichihashi et al examined the effect of S-1 molecular sieves on the activity of the gas phase Beckmann rearrangement reaction. Conversion and selectivity were found to reach 100% and 80%, respectively. The selectivity of caprolactam which is used as a solvent of methanol can reach more than 95 percent. The authors believe that the terminal silicon hydroxyl groups modified by methanol play a very important role in increasing the selectivity of caprolactam, and thus it appears that the terminal hydroxyl groups in the molecular sieve are detrimental to the beckmann rearrangement reaction, but the structure of the silicon hydroxyl nests in the molecular sieve significantly contributes to the gas phase beckmann rearrangement reaction, which is the active center of the reaction.
The gas phase rearrangement of medium petrifaction in caprolactam has been researched for a long time and made a certain progress. By using S-1 and TS-1 molecular sieves as catalysts and through technical iteration for many years, the Beckmann rearrangement evaluation result is that the conversion rate is 99.9%, the selectivity is 96.5%, and the Beckmann rearrangement evaluation result is higher than the technical index disclosed by Japanese Sumitomo, and the Beckmann rearrangement technology is pilot-plant tested in 2009 and identified through the technology in 2010. Compared with sulfuric acid process, the gas phase rearrangement process has the advantages of easy dissociation of the product, no need of ammonia gas, no by-product of ammonium sulfate and high atom economy. However, the method has the defects of serious reaction coking, low caprolactam yield, short catalyst life and the like.
Compared with the gas phase Beckmann rearrangement reaction, the liquid phase Beckmann rearrangement reaction has the advantages of mild reaction conditions, high caprolactam yield and the like, but the difficulty is to develop an efficient catalyst with a longer service life.
In the industrial production of caprolactam, sulfuric acid or oleum is often used as a catalyst, and caprolactam is produced by the beckmann rearrangement reaction of cyclohexanone oxime in the presence of sulfuric acid or oleum. The process generally adopts a mode of material external circulation heat transfer, namely, fuming sulfuric acid is added into a system from a circulating pump inlet in a rearrangement reactor and mixed with rearrangement liquid, heat is transferred out of a reaction system through a circulating pipeline heat exchanger, and the circulation liquid with the reduced temperature enters a mixer and is rapidly mixed with added cyclohexanone oxime to react to form heavy liquid. The process is mature and simple, so that the caprolactam is basically produced by the method in industry.
The ionic liquid can be used as a catalyst for liquid-phase Beckmann rearrangement reaction. An ionic liquid refers to a compound consisting entirely of anions and cations that is liquid at or near room temperature. The ionic liquid has the following advantages: high density reaction activity, difficult volatilization, low vapor pressure, high chemical property, thermal stability, strong dissolving capacity, good catalytic activity, adjustable structure, strong designability, incombustibility and no toxicity. At present, dialkyl substituted imidazolium salts are most widely used because of their ease of synthesis and their good physical and chemical stability. The ionic liquid method generally comprises the steps of firstly carrying out rearrangement in an ionic liquid/organic solvent, then using the organic solvent to extract caprolactam, and then realizing separation of the caprolactam and a catalyst by a solvent extraction method, wherein the ionic liquid, the catalyst and the organic solvent can be recycled. In spite of the above advantages, catalysts such as V, P, etc. used under ionic liquid conditions are generally toxic, and in addition, there are problems of stability of ionic liquid and separation of products, which are far from practical use.
The ion exchange resin is an insoluble polymer compound having a network structure and having a functional group (active group for exchanging ions). Generally, an ion exchange resin having catalytic activity for the beckmann rearrangement reaction of cyclohexanone oxime is a strongly acidic ion exchange resin having a sulfonic acid group. The catalyst has the advantages of environmental protection, high efficiency, recoverability, no use of noble metals and the like, but also has the disadvantages of high cost, difficult regeneration after inactivation and the like.
The solid acid catalyst is a rearrangement reaction in a liquid phase by using a solid strong acid as a functional group, and compared with sulfuric acid, the solid acid catalyst has the advantage of not generating an ammonium sulfate by-product. Patent ZL201811612796.0 discloses a preparation method of a molecular sieve-supported double-active-component solid acid catalyst, and the catalyst can be used for efficiently catalyzing cyclohexanone oxime to generate caprolactam, and has the advantages of high catalytic efficiency, high caprolactam yield and no production of ammonium sulfate by-products. The service life of the catalyst is more than 4000 h. The deactivation mechanism is not only carbon deposition coverage, but is due to a variety of factors.
In order to reduce the production cost of caprolactam, the invention provides a method capable of regenerating a catalyst in situ, the activity of the catalyst can be recovered only by liquid phase treatment for many times without discharging the deactivated catalyst, and the activated catalyst can completely recover the original catalytic performance.
Disclosure of Invention
In view of this, the present invention aims to provide an in-situ regeneration method of a liquid-phase beckmann rearrangement catalyst, and provides an in-situ regeneration method of a liquid-phase beckmann rearrangement catalyst. The method comprises the steps of sequentially using three solutions to treat the inactivated catalyst, firstly using a weak alkaline solution to open the pore passages of the molecular sieve catalyst and remove attached oligomers; then using an acid solution to remove amide substances attached to the active groups of the catalyst and clean the surface of the metal oxide; finally, a strong acid solution is used to replenish the detached strong acid groups on the catalyst.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
the deactivated catalyst is molecular sieve supported catalyst from liquid phase Beckmann rearrangement reaction and its regeneration process includes the following steps: s1, emptying reactants in a tubular reactor filled with a Beckmann rearrangement catalyst;
s2, preparing a cleaning solution A, and cleaning the reaction tube by using the cleaning solution A;
s3, introducing hot air into the reaction tube obtained in the step S2, and drying;
s4, preparing a cleaning solution B, and cleaning the reaction tube by using the cleaning solution B;
s5, introducing hot air into the reaction tube obtained in the step S4, and drying;
s6, preparing an activating solution C, and cleaning the reaction tube by using the activating solution C;
s7, hot air is introduced into the reaction tube obtained in the step S6, and drying is carried out.
In the step S1, the beckmann rearrangement catalyst is filled in the tubular reactor, and the filled catalyst is a molded granular catalyst, preferably, the particle diameter is 6-10mm.
Further, in the step S2, the cleaning solution a is a weakly alkaline organic solution; the solvent is one or more than two of methanol, ethanol, isopropanol, tert-butanol, ethylene glycol, glycerol, acetonitrile, benzonitrile, dichloromethane, chloroform, 1, 2-tetrachloroethane, carbon tetrachloride, methyl formate, methyl acetate and ethyl acetate;
the alkaline component is one or more of ammonia gas, sodium hydroxide, potassium hydroxide, ethylamine, ethylenediamine and triethylamine, and the concentration of the alkaline component is 1-10%, preferably 2-5%.
Further, in the step S2, the weight ratio of the cleaning liquid A to the deactivated catalyst in the step S1 is 2-100, preferably 10-20; the cleaning time for cleaning the reaction tube by the cleaning liquid A in the S2 is 0.5-10h, preferably 2-5h, and the cleaning temperature is 20-80 ℃. Preferably 40-50 deg.C.
Further, in the step S3, the drying temperature is 50-200 ℃, preferably 80-120 ℃, and the drying time is 2-4h.
In the step S4, the cleaning solution B is a strong acid aqueous solution, and the solvent is one or more than two of methanol, ethanol, isopropanol, tert-butanol, ethylene glycol, glycerol, acetonitrile, benzonitrile, dichloromethane, chloroform, 1, 2-tetrachloroethane, carbon tetrachloride, methyl formate, methyl acetate and ethyl acetate;
the acidic component is one or more of formic acid, acetic acid, trichloroacetic acid, sulfuric acid, picric acid, methanesulfonic acid, benzenesulfonic acid, methylbenzenesulfonic acid and trifluorobenzene sulfonic acid, and the concentration of the acidic component is 0.2-15%, preferably 1-5%.
Further, in the step S4, the weight ratio of the cleaning liquid B to the deactivated catalyst in the step S1 is 5-200, preferably 20-50;
the cleaning time of the cleaning solution B for cleaning the test tube is 10-50h, preferably 10-20h, and the cleaning temperature is 50-150 ℃. Preferably 80-120 ℃.
Further, in the step S5, the drying temperature is 50-200 ℃, preferably 80-120 ℃, and the drying time is 2-4h;
in the step S6, the activating solution C is an aqueous solution of a strong acid, the acid is one or two or more of trichloroacetic acid, methanesulfonic acid, sulfamic acid, mellitic acid, picric acid, benzenesulfonic acid, toluenesulfonic acid, and trifluorobenzene sulfonic acid, and the concentration of the solution of the activating solution C is 0.1-20%, preferably 5-10%.
In the step S6, the weight ratio of the activating solution C to the deactivated catalyst in the step S1 is 1-10, preferably 2-4; the activation time is 10-50h, preferably 10-20h, and the activation temperature is 30-100 deg.C, preferably 50-70 deg.C.
In the step S7, the drying temperature is 80-200 ℃, preferably 100-120 ℃, and the drying time is 8-10h.
Compared with the prior art, the in-situ regeneration method of the liquid-phase Beckmann rearrangement catalyst has the following beneficial effects:
1. the regeneration method for the liquid phase Beckmann rearrangement catalyst can be used for in-situ regeneration, the catalyst loaded in the reaction tube does not need to be unloaded, and the operation labor is small.
2. The method for regenerating the liquid-phase Beckmann rearrangement catalyst can completely recover the activity and the service life of the catalyst.
3. The method for regenerating the liquid phase Beckmann rearrangement catalyst has the advantages of simple raw materials and low cost, and is suitable for industrial production.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The present invention will be described in detail below with reference to examples.
Example 1
Dissolving cyclohexanone oxime in acetonitrile, preparing 25% cyclohexanone oxime acetonitrile solution, placing a catalyst in a fixed bed reactor, heating the fixed bed reactor to 110 ℃, and enabling the cyclohexanone oxime solution to pass through the fixed bed at a reaction space velocity of 1h -1 . The obtained cyclohexanone oxime conversion rate is 99.98 percent, the caprolactam selectivity is 99.87 percent, the catalyst is deactivated after 4105 hours of reaction, and the cyclohexanone oxime conversion rate is 95.00 percent.
Example 2
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
A total of 100kg of cleaning solution A was prepared, the cleaning solution A being a methanol solution of ammonia having a concentration of 5%. Heating the fixed bed reactor to 50 ℃, and slowly introducing the cleaning solution A into the fixed bed reactor for cleaning for 5 hours. After the cleaning, hot air of 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 2h.
A total of 300kg of cleaning solution B was prepared, the component of cleaning solution B was a methanol solution of acetic acid, and the concentration of acetic acid was 5%. Heating the fixed bed reactor to 100 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 20 hours. After the cleaning, hot air of 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
80kg of activating solution C is prepared, the component of the activating solution C is an aqueous solution of sulfamic acid, and the concentration of the sulfamic acid is 10%. Heating the fixed bed reactor to 50 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 18h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Example 3
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated and the fixed bed was packed with 10kg of a catalyst in the form of pellets having a particle diameter of 6mmm.
A total of 150kg of cleaning solution A was prepared, the cleaning solution A being an acetonitrile solution of ammonia having a concentration of 5%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the cleaning fluid A into the fixed bed reactor for cleaning for 4 hours. After the cleaning, hot air of 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 2h.
200kg of cleaning solution B is prepared, the component of the cleaning solution B is an ethanol solution of sulfuric acid, and the concentration of the sulfuric acid is 2%. And heating the fixed bed reactor to 100 ℃, and slowly introducing the cleaning liquid B into the fixed bed reactor for cleaning for 15 hours. After the cleaning, hot air of 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 2h.
40kg of activation solution C is prepared, the component of the activation solution C is an aqueous solution of sulfuric acid, and the concentration of sulfamic acid is 10%. Heating the fixed bed reactor to 50 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 15h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Example 4
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
A total of 150kg of cleaning solution A was prepared, the cleaning solution A being an ethylene glycol solution of sodium hydroxide having a sodium hydroxide concentration of 5%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the cleaning solution A into the fixed bed reactor for cleaning for 2 hours. After the cleaning, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
200kg of cleaning solution B is prepared, the component of the cleaning solution B is glycol solution of benzenesulfonic acid, and the concentration of benzenesulfonic acid is 5%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 20 hours. After the cleaning, hot air of 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
80kg of activating solution C is prepared, the component of the activating solution C is a mellitic acid aqueous solution, and the concentration of the mellitic acid is 5%. Heating the fixed bed reactor to 70 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 10 hours. After activation, hot air at 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 8h.
Example 5
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated and the fixed bed was packed with 10kg of a catalyst in the form of pellets having a particle diameter of 6mmm.
120kg of cleaning solution A is prepared, the component of the cleaning solution A is 1, 2-tetrachloroethane solution of potassium hydroxide, and the concentration of the potassium hydroxide is 2 percent. Heating the fixed bed reactor to 50 ℃, and slowly introducing the cleaning solution A into the fixed bed reactor for cleaning for 4 hours. After the cleaning, hot air at 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
A total of 150kg of cleaning solution B was prepared, the component of cleaning solution B was a tert-butanol solution of toluenesulfonic acid, and the concentration of toluenesulfonic acid was 5%. Heating the fixed bed reactor to 100 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 16h. After the cleaning, hot air at 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
80kg of activating solution C is prepared, the component of the activating solution C is an aqueous solution of trifluorobenzene sulfonic acid, and the concentration of the trifluorobenzene sulfonic acid is 5%. Heating the fixed bed reactor to 50 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 12h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Example 6
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
120kg of cleaning solution A is prepared, the component of the cleaning solution A is ethyl acetate solution of ethylenediamine, and the concentration of the ethylenediamine is 2.5%. Heating the fixed bed reactor to 50 ℃, and slowly introducing the cleaning solution A into the fixed bed reactor for cleaning for 5 hours. After the cleaning, hot air at 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
200kg of cleaning solution B is prepared, the component of the cleaning solution B is an ethyl acetate solution of trichloroacetic acid, and the concentration of trichloroacetic acid is 5%. Heating the fixed bed reactor to 140 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 20 hours. After the cleaning, hot air at 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
60kg of activating solution C is prepared, the component of the activating solution C is picric acid water solution, and the concentration of the picric acid is 10%. Heating the fixed bed reactor to 70 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 20h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Example 7
Dissolving cyclohexanone oxime in acetonitrile to prepare 25 percent cyclohexanone oxime acetonitrile solution. The catalysts obtained in examples 2 to 6 were used. Heating a fixed bed reactor to 110 ℃, and enabling the cyclohexanone oxime solution to pass through the fixed bed at a reaction space velocity of 1h -1 The reaction was evaluated, and when the cyclohexanone oxime conversion was less than 95%, the catalyst was considered to have been deactivated. The evaluation results are shown in Table 1.
Comparative example 1
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
A total of 120kg of cleaning solution A was prepared, and the cleaning solution A contained ethanol. Heating the fixed bed reactor to 50 ℃, and slowly introducing the cleaning solution A into the fixed bed reactor for cleaning for 5 hours. After the cleaning, hot air at 100 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
A total of 200kg of cleaning solution B was prepared, and the component of the cleaning solution B was 1, 2-tetrachloroethane. Heating the fixed bed reactor to 140 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 20 hours. After the cleaning, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
60kg of activating solution C is prepared, the component of the activating solution C is an aqueous solution of benzenesulfonic acid, and the concentration of benzenesulfonic acid is 10%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the activation liquid C into the fixed bed reactor for activation, wherein the activation time is 20h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Comparative example 2
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
The total amount of the activating solution C is 100kg, the component of the activating solution C is an aqueous solution of benzenesulfonic acid, and the concentration of benzenesulfonic acid is 10%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 20h. After activation, hot air at 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
Comparative example 3
The deactivated liquid phase beckmann rearrangement catalyst is from example 1.
The reactants in the fixed bed were evacuated, and 10kg of a catalyst having a particle size of 6mmm was packed in the fixed bed.
200kg of cleaning solution B is prepared, the component of the cleaning solution B is an ethanol solution of acetic acid, and the concentration of the acetic acid is 5%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the cleaning solution B into the fixed bed reactor for cleaning for 20 hours. After the cleaning, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 4h.
The total amount of the activating solution C is 100kg, the component of the activating solution C is an aqueous solution of benzenesulfonic acid, and the concentration of benzenesulfonic acid is 10%. Heating the fixed bed reactor to 80 ℃, and slowly introducing the activating solution C into the fixed bed reactor for activation, wherein the activation time is 20h. After the activation, hot air of 120 ℃ is introduced into the fixed bed reactor for drying, and the drying time is 10h.
As can be seen from examples 2 to 6 and comparative examples 1 to 3, in the treated examples 2 to 6, the service life of the regenerated catalyst is almost the same as that of the regenerated catalyst, and the cyclohexanone oxime conversion rate and caprolactam selectivity can be ensured as well, and the catalyst regeneration method for the liquid phase Beckmann rearrangement reaction of the present invention can completely recover the activity and service life of the catalyst. The regeneration method of the catalyst for the liquid phase Beckmann rearrangement reaction has the advantages of simple raw materials, low price and suitability for industrial production.
TABLE 1
Figure BDA0004050538660000121

Claims (10)

1. An in-situ regeneration method of a liquid phase Beckmann rearrangement catalyst is characterized in that: the deactivated catalyst is molecular sieve supported catalyst from liquid phase Beckmann rearrangement reaction and its regeneration process includes the following steps: s1, emptying reactants in a tubular reactor filled with a Beckmann rearrangement catalyst; s2, preparing a cleaning solution A, and cleaning the reaction tube by using the cleaning solution A;
s3, introducing hot air into the reaction tube obtained in the step S2, and drying;
s4, preparing a cleaning solution B, and cleaning the reaction tube by using the cleaning solution B;
s5, introducing hot air into the reaction tube obtained in the step S4, and drying;
s6, preparing an activating solution C, and cleaning the reaction tube by using the activating solution C;
s7, hot air is introduced into the reaction tube obtained in the step S6, and drying is carried out.
2. The method for in-situ regeneration of a liquid-phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S1, the beckmann rearrangement catalyst is filled in the tubular reactor, and the filled catalyst is a molded granular catalyst, preferably, the particle diameter is 6-10mm.
3. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S2, the cleaning solution A is a weakly alkaline organic solution;
the solvent is one or more than two of methanol, ethanol, isopropanol, tert-butanol, ethylene glycol, glycerol, acetonitrile, benzonitrile, dichloromethane, chloroform, 1, 2-tetrachloroethane, carbon tetrachloride, methyl formate, methyl acetate and ethyl acetate;
the alkaline component is one or more of ammonia gas, sodium hydroxide, potassium hydroxide, ethylamine, ethylenediamine and triethylamine, and the concentration of the alkaline component is 1-10%, preferably 2-5%.
4. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S2, the weight ratio of the cleaning liquid A to the deactivated catalyst in the step S1 is 2-100, preferably 10-20;
the cleaning time for cleaning the reaction tube by the cleaning solution A in the S2 is 0.5-10h, preferably 2-5h, and the cleaning temperature is 20-80 ℃, preferably 40-50 ℃.
5. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S3, the drying temperature is 50-200 ℃, preferably 80-120 ℃, and the drying time is 2-4h.
6. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S4, the cleaning solution B is a strong acid aqueous solution, and the solvent is one or more than two of methanol, ethanol, isopropanol, tert-butanol, ethylene glycol, glycerol, acetonitrile, benzonitrile, dichloromethane, chloroform, 1, 2-tetrachloroethane, carbon tetrachloride, methyl formate, methyl acetate and ethyl acetate;
the acidic component is one or more of formic acid, acetic acid, trichloroacetic acid, sulfuric acid, picric acid, methanesulfonic acid, benzenesulfonic acid, methylbenzenesulfonic acid, and trifluorobenzene sulfonic acid, and the concentration of the acidic component is 0.2-15%, preferably 1-5%.
7. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S4, the weight ratio of the cleaning liquid B to the deactivated catalyst in the step S1 is 5-200, preferably 20-50;
the cleaning time of the cleaning solution B for cleaning the test tube is 10-50h, preferably 10-20h, and the cleaning temperature is 50-150 ℃. Preferably 80-120 ℃.
8. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S5, the drying temperature is 50-200 ℃, preferably 80-120 ℃, and the drying time is 2-4h;
in the step S6, the activating solution C is an aqueous solution of a strong acid, the acid is one or two or more of trichloroacetic acid, methanesulfonic acid, sulfamic acid, mellitic acid, picric acid, benzenesulfonic acid, toluenesulfonic acid, trifluorobenzene sulfonic acid, and the solution concentration of the activating solution C is 0.1-20%, preferably 5-10%.
9. The method for in-situ regeneration of a liquid-phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S6, the weight ratio of the activating solution C to the deactivated catalyst in the step S1 is 1-10, preferably 2-4;
the activation time is 10-50h, preferably 10-20h, and the activation temperature is 30-100 deg.C, preferably 50-70 deg.C.
10. The method for in-situ regeneration of a liquid phase beckmann rearrangement catalyst according to claim 1, wherein: in the step S7, the drying temperature is 80-200 ℃, preferably 100-120 ℃, and the drying time is 8-10h.
CN202310039709.1A 2023-01-12 2023-01-12 In-situ regeneration method of liquid phase Beckmann rearrangement catalyst Pending CN115957811A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310039709.1A CN115957811A (en) 2023-01-12 2023-01-12 In-situ regeneration method of liquid phase Beckmann rearrangement catalyst

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310039709.1A CN115957811A (en) 2023-01-12 2023-01-12 In-situ regeneration method of liquid phase Beckmann rearrangement catalyst

Publications (1)

Publication Number Publication Date
CN115957811A true CN115957811A (en) 2023-04-14

Family

ID=87361806

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310039709.1A Pending CN115957811A (en) 2023-01-12 2023-01-12 In-situ regeneration method of liquid phase Beckmann rearrangement catalyst

Country Status (1)

Country Link
CN (1) CN115957811A (en)

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5292880A (en) * 1992-05-11 1994-03-08 Mobil Oil Corporation Synthesis of caprolactam using catalysts
JPH1157483A (en) * 1997-08-22 1999-03-02 Sumitomo Chem Co Ltd Catalyst for preparing epsilon-caprolactam and preparation of epsilon-caprolactam by using the same
US6265574B1 (en) * 1999-02-09 2001-07-24 Sumitomo Chemical Company, Limited Process for producing ε-caprolactam
JP2003320260A (en) * 2002-02-27 2003-11-11 Sumitomo Chem Co Ltd METHOD FOR REGENERATING epsilon-CAPROLACTAM-PRODUCING CATALYST AND METHOD FOR PRODUCING epsilon-CAPROLACTAM
JP2005224752A (en) * 2004-02-16 2005-08-25 Sumitomo Chemical Co Ltd METHOD OF REGENERATING epsilon-CAPROLACTAM-PRODUCING CATALYST AND METHOD OF PRODUCING epsilon-CAPROLACTAM
CN1724366A (en) * 2004-06-30 2006-01-25 住友化学株式会社 Method for manufacturing zeolite and method for manufacturing epsilon-caprolatam
CN101099935A (en) * 2006-07-04 2008-01-09 住友化学株式会社 Process for regenerating catalyst for producing epsilon-caprolactam and process for producing epsilon-caprolactam
CN101429149A (en) * 2007-11-08 2009-05-13 中国石油化工股份有限公司 Method for producing Epsilon-hexanolactam with cyclohexanone oxime gas-phase beckmann rearrangement
CN103551210A (en) * 2013-11-06 2014-02-05 中国石油化工股份有限公司 Method for regenerating ion exchange resin based on fluidized bed
CN105728035A (en) * 2016-03-17 2016-07-06 中国天辰工程有限公司 Method for regenerating deactivated catalysts for liquid-phase cyclohexanone ammoximation technology
CN111151307A (en) * 2019-12-31 2020-05-15 衢州巨化锦纶有限责任公司 Regeneration method of ion exchange resin for refining caprolactam water solution
CN112495453A (en) * 2020-12-20 2021-03-16 衢州巨化锦纶有限责任公司 Regeneration method of ion exchange resin for refining caprolactam
CN114917940A (en) * 2022-06-30 2022-08-19 中国天辰工程有限公司 Preparation method of caprolactam ammoniation catalyst

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5292880A (en) * 1992-05-11 1994-03-08 Mobil Oil Corporation Synthesis of caprolactam using catalysts
JPH1157483A (en) * 1997-08-22 1999-03-02 Sumitomo Chem Co Ltd Catalyst for preparing epsilon-caprolactam and preparation of epsilon-caprolactam by using the same
US6265574B1 (en) * 1999-02-09 2001-07-24 Sumitomo Chemical Company, Limited Process for producing ε-caprolactam
JP2003320260A (en) * 2002-02-27 2003-11-11 Sumitomo Chem Co Ltd METHOD FOR REGENERATING epsilon-CAPROLACTAM-PRODUCING CATALYST AND METHOD FOR PRODUCING epsilon-CAPROLACTAM
JP2005224752A (en) * 2004-02-16 2005-08-25 Sumitomo Chemical Co Ltd METHOD OF REGENERATING epsilon-CAPROLACTAM-PRODUCING CATALYST AND METHOD OF PRODUCING epsilon-CAPROLACTAM
CN1724366A (en) * 2004-06-30 2006-01-25 住友化学株式会社 Method for manufacturing zeolite and method for manufacturing epsilon-caprolatam
CN101099935A (en) * 2006-07-04 2008-01-09 住友化学株式会社 Process for regenerating catalyst for producing epsilon-caprolactam and process for producing epsilon-caprolactam
CN101429149A (en) * 2007-11-08 2009-05-13 中国石油化工股份有限公司 Method for producing Epsilon-hexanolactam with cyclohexanone oxime gas-phase beckmann rearrangement
CN103551210A (en) * 2013-11-06 2014-02-05 中国石油化工股份有限公司 Method for regenerating ion exchange resin based on fluidized bed
CN105728035A (en) * 2016-03-17 2016-07-06 中国天辰工程有限公司 Method for regenerating deactivated catalysts for liquid-phase cyclohexanone ammoximation technology
CN111151307A (en) * 2019-12-31 2020-05-15 衢州巨化锦纶有限责任公司 Regeneration method of ion exchange resin for refining caprolactam water solution
CN112495453A (en) * 2020-12-20 2021-03-16 衢州巨化锦纶有限责任公司 Regeneration method of ion exchange resin for refining caprolactam
CN114917940A (en) * 2022-06-30 2022-08-19 中国天辰工程有限公司 Preparation method of caprolactam ammoniation catalyst

Similar Documents

Publication Publication Date Title
US10195592B2 (en) Zirconium-based metal-organic frameworks as catalyst for transfer hydrogenation
Corma et al. Modified faujasite zeolites as catalysts in organic reactions: Esterification of carboxylic acids in the presence of HY zeolites
CN101773860A (en) Carbon-based solid acid catalyst synthesized by one-step hydrothermal carbonization process
CN114539207B (en) Method for preparing lactide and catalyst
CN103240116B (en) Catalyst for producing piperazidine and triethylenediamine and preparation method thereof
CN114381006B (en) Covalent organic framework material BM-SO with acid-base dual functions 3 H, preparation method and application thereof
CN101537369A (en) ZSM-5 catalyst and preparation thereof and use thereof
CN113649062A (en) Catalyst for synthesizing 6-aminocapronitrile, method for preparing same, and method for synthesizing 6-aminocapronitrile using same
CN103130768B (en) Preparation method of compound with 1,3-dioxane structure
CN101284767A (en) Process for preparing cyclohexanol by cyclohexene hydration reaction
CN108126748B (en) Alkaline monolithic catalyst with regular pore channels and preparation method and application thereof
CN111646921A (en) Catalyst regeneration method for preparing hexamethylene diamine key intermediate 6-aminocapronitrile by caprolactam method
WO2022165662A1 (en) Method for preparing glycolic acid and methyl glycolate by hydrolysis of methyl methoxyacetate and methoxyacetic acid
CN115957811A (en) In-situ regeneration method of liquid phase Beckmann rearrangement catalyst
CN101638397A (en) Method for synthesizing N-methylmorpholine with granular solid superacid as catalyst
CN112058313B (en) Composite catalyst, preparation method thereof and application thereof in citral synthesis
CN100500628C (en) Method for preparing 1,3-methyl glycol by catalytic hydrogenation of 3-hydroxy propanal
CN113429534A (en) Preparation method of high-stability strong-basicity porous ion exchange material
CN107930693B (en) Modified resin catalyst and method for removing residual formaldehyde in 3-methyl-3-butene-1-alcohol solution
CN114011468A (en) Copper carbene catalyst and preparation method and application thereof
CN103709010A (en) Method for synthesizing cyclohexanol by reacting cyclohexene, carboxylic acid and water
CN111944083B (en) Preparation method of modified macroporous acidic cation exchange resin
CN115368260B (en) Synthesis method of N-vinylformamide
CN118287140B (en) Solid acid catalyst, preparation method and application of catalyst in catalytic synthesis of ethyl trichloroacetate
CN108273556A (en) A kind of preparation method of the fluorine based on MOF/chlorine exchange catalysts

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination