CN109289902A - A method of improving molding MFI molecular sieve catalytic Beckmann rearrangement performance - Google Patents
A method of improving molding MFI molecular sieve catalytic Beckmann rearrangement performance Download PDFInfo
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- CN109289902A CN109289902A CN201811231121.1A CN201811231121A CN109289902A CN 109289902 A CN109289902 A CN 109289902A CN 201811231121 A CN201811231121 A CN 201811231121A CN 109289902 A CN109289902 A CN 109289902A
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- molecular sieve
- catalyst
- aqueous solution
- beckmann rearrangement
- mfi molecular
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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
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D201/00—Preparation, separation, purification or stabilisation of unsubstituted lactams
- C07D201/02—Preparation of lactams
- C07D201/04—Preparation of lactams from or via oximes by Beckmann rearrangement
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D223/00—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom
- C07D223/02—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings
- C07D223/06—Heterocyclic compounds containing seven-membered rings having one nitrogen atom as the only ring hetero atom not condensed with other rings 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
- C07D223/08—Oxygen atoms
- C07D223/10—Oxygen atoms attached in position 2
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Abstract
The invention discloses a kind of methods of molding MFI catalyst activity, selectivity and stability for improving and being applied to Cyclohexanone-Oxime Gas Phase Beckmann Rearrangement, it specifically uses and is contacted containing the extruded mouldings such as MFI structure molecular sieve, silica solution, sesbania powder catalyst with the alkaline aqueous solution containing tetrapropyl cation, it is separated by solid-liquid separation, improved catalyst is made in drying and roasting.Activity, selectivity and the more unmodified catalyst of stability of the improved catalyst of the method for the present invention preparation significantly improve.
Description
Technical field
The present invention relates to a kind of improve to live applied to the molding MFI catalyst of Cyclohexanone-Oxime Gas Phase Beckmann Rearrangement
Property, the method for selectivity and stability.
Background technique
Caprolactam (ε-Caprolactam, write a Chinese character in simplified form CPL) is important organic chemical industry's monomer of synthesizing polyamides 6.Work at present
The concentrated sulfuric acid or oleum is mainly used to carry out phase rearrangement of cyclohexanone oxime liquid reaction for catalyst to prepare in industry.The technique skill
Art is more mature, and cyclohexanone oxime conversion ratio and caprolactam selectivity are all higher, and product quality is also stable, but the technique is maximum
The shortcomings that be that serious environmental protection problem is caused using the strong concentrated sulfuric acid or oleum of corrosivity；In addition, the every life of the technique
Produce the inefficient fertilizer of ammonium sulfate of 1t cyclohexanone oxime meeting by-product 0.64t.
In order to develop with greater activity and selectivity green heterogeneous catalyst, the institution of scientific research of countries in the world and
Industry investment very great explores more cyclohexanone-oxime Beckmann rearrangement reaction catalyst, main to have oxide solid
Body acid, the mixed oxide solid acid and all kinds of molecular sieve catalysts etc. of dipping boric acid or phosphoric acid.Wherein USP5914398,
The relevant reports such as USP5942613, USP1709024 and USP3586668 show that the oxide catalyst service life is shorter, cyclohexanone oxime
Conversion ratio and caprolactam selectivity be not high, and regeneration effect is undesirable.Chinese patent literature CN 1724366 B, CN
102432032 B, CN 102050464 B, CN 102233277 A and 101786010 B of CN report using high silica alumina ratio or
Person's pure silicon MFI molecular sieve is catalyst, and cyclohexanone oxime conversion ratio and caprolactam selectivity are higher, and regeneration effect is also fine, has
Important industrial prospect.
For MFI molecular sieve catalyst, generallys use after hydro-thermal method synthesizes MFI molecular screen primary powder, need further to locate
Reason can just obtain the catalyst of high cyclohexanone oxime conversion ratio and caprolactam selectivity.USP5403801 is in order to improve S-1 and TS-
The reactivity worth of 1 pair of Beckmann rearrangement, by MFI molecular sieve in different ammonium salt solutions and at least one alkaline matter (front three
Amine, tetrapropylammonium hydroxide) or aqueous ammonia conditions under processing on its active influence.At 350 DEG C, air speed 8h-1, methanol is molten
Under agent reaction condition, cyclohexanone oxime conversion ratio 99.5% after TOS=6.25h, caprolactam selectivity 96.5%.CN1119282C
MFI molecular sieve is contacted with organic base, improves the conversion ratio of oxime and the selectivity of caprolactam.CN1883803A, which is disclosed, to be adopted
With hydrofluoric acid treatment MFI molecular sieve, the conversion ratio of oxime and the selectivity of caprolactam also can be improved.These patents are all using powder
Last shape catalyst, handles powder catalyst, improve oxime conversion ratio and caprolactam selectivity.They cannot be direct
Applied to industrialized unit, for industrial applications, molecular sieve could use after must forming, but need to be added in forming process
The various auxiliary agents such as silica solution, these auxiliary agents frequently result in catalyst activity, selectivity and stability decline.Therefore, it is necessary to grind
Study carefully processing method after molding, still there is high activity, highly selective and stability vapour phase rearrangement catalyst after being formed.
1014683198 B of Chinese patent literature CN 1322927 C and CN divides silicon high after molding/aluminium ratio MFI structure
Son sieve is used for rearrangement reaction after contacting with the alkaline buffer solution of nitrogenous compound.In cyclohexanone oxime weight space velocity (WHSV=
16h-1) under react 8h after, cyclohexanone oxime conversion ratio 99.8%, caprolactam selectivity 95.9%.101786010 B of CN is first
Molding S-1 catalyst is handled using the aqueous solution of nitrogenous compound, is then handled, is obtained with the aqueous solution of fluorochemical again
Vapor phase beckmann rearrangement reaction catalyst.Through detecting, in cyclohexanone oxime mass space velocity (WHSV=2h-1) under react 100h after, ring
The selectivity that the conversion ratio of hexanone oxime is greater than 99.8%, caprolactam is greater than 95.5%.
Although in conclusion reacting the catalyst catalytic of caprolactam processed by the molding vapour phase rearrangement of prior art preparation
It can be it is also possible that but it is still necessary to obtaining more high activity, selectivity and stability to molding rear catalyst post-processing further research
The vapour phase rearrangement catalysts that can industrially use.
Summary of the invention
The purpose of the invention is to overcome in the prior art molecular sieve molded catalyst containing MFI structure since addition silicon is viscous
Knot agent and the shortcomings that cause catalyst activity and stability to decline, provided for molding MFI catalyst and a kind of improve it and be used for hexamethylene
The improved method of catalytic performance and stability when ketoxime gas phase beckmann rearrangement prepares caprolactam reaction.The method of the present invention is made
MFI molecular sieve is improved, molecular sieve molded catalyst containing MFI structure made from method of the invention carries out cyclohexanone oxime gas phase shellfish
When gram graceful rearrangement reaction, activity, selectivity and the more unmodified catalyst of stability of improved catalyst are significantly improved.
To achieve the above object, the technical solution adopted by the present invention are as follows:
A method of molding MFI molecular sieve catalytic Beckmann rearrangement performance being improved, this method is made modified MFI points
Son sieve, detailed process is extruded moulding after mixing containing MFI structure molecular sieve with bonding agent, extrusion aid, after extruded moulding
Catalyst with containing tetrapropyl cation alkaline aqueous solution handle, processing after the completion of be separated by solid-liquid separation, isolated solid is done
Dry roasting obtains modified MFI molecular sieve, wherein bonding agent is silica solution, and extrusion aid is polyethylene glycol 400 and sesbania powder.
As currently preferred, the silica solution use PH for 9.3 30.56wt% alkaline silica sol.
As currently preferred, the mass ratio of each substance contained in the extruded moulding technique is to contain MFI structure
Molecular sieve: silica solution: sesbania powder: polyethylene glycol 400: water=1:0.21:0.025:0.018:0.48.
As currently preferred, the alkaline aqueous solution containing tetrapropyl cation is TPAOH aqueous solution, or
The mixture of TPABr and amine compound, the mixed aqueous solution of alcohol amine compound or two kinds of aqueous solutions.
As currently preferred, the TPABr and amine compound, alcohol amine compound mixed aqueous solution in
The molar ratio of TPABr and amine compound, alcohol amine compound is 1:1:1.
As currently preferred, the amine compound is ethylenediamine, and alcohol amine compound is ethanol amine.
As currently preferred, the alkaline aqueous solution concentration containing tetrapropyl cation is 20~30wt%.
As currently preferred, the alkaline aqueous solution dosage containing tetrapropyl cation is that dry extruded moulding is urged
5~20 times of agent weight.
As currently preferred, with the catalyst of the alkaline aqueous solution processing extruded moulding containing tetrapropyl cation
When, the temperature of processing is 120~170 DEG C, and the time of the contact is 6~48h.
It is as currently preferred, isolated solid is dry at 60~120 DEG C, roasting 6 at 450~550 DEG C~
12h。
Compared with prior art, the invention has the benefit that
1, present invention advantageously employs the alkaline aqueous solutions containing tetrapropyl cation to contain MFI structure to extruded moulding
Molecular sieve handled, processing method is simple, easy to operate, and the catalytic performance of modified MFI molecular sieve obtained more before modified has
It is significant to improve.
2, molecular sieve molded catalyst containing MFI structure made from method of the invention carries out cyclohexanone oxime gas phase Beckman
When rearrangement reaction, activity, selectivity and the more unmodified catalyst of stability of improved catalyst are significantly improved.
Specific embodiment
Below with reference to embodiment, the present invention is described in further detail.
MFI molecular sieve is formed in the embodiment of the present invention and comparative example uses S-1 molecular sieve, preparation process are as follows: according to pre-
Molar ratio { the tetrapropylammonium hydroxide (TPAOH): ethyl orthosilicate (TEOS): H respectively formed in the preceding body liquid of synthesis of molecular sieve2O
=0.2:1:20 } it weighs and is added sequentially in beaker, 3h is stirred, 70 DEG C of row's alcohol 2h are then risen to, 45 DEG C are aged for 24 hours, and 170 DEG C
Crystallization 48h.After crystallization, is roasted at 400~600 DEG C after separation is dry and S-1 molecular sieve is made.
Comparative example 1
By quality weigh 12.005g S-1 molecular sieve, 8.313g 30.56wt% alkaline silica sol (pH=9.3),
0.211g polyethylene glycol 400,0.303g sesbania powder are uniformly mixed, the mold extrusion for being 2.5mm with aperture；60 DEG C of dryings, 400
DEG C roasting 6h, obtain dry extruded moulding catalyst sample.
Comparative example 2
It will be according to the resulting extruded moulding catalyst sample of comparative example 1, with ammonium nitrate and ammonium hydroxide mixed solution according to quality
It is mixed than 1:10, modified 1h, is modified three times, after separation of solid and liquid, a kind of gas is made in 60 DEG C of dryings, 450 DEG C of roasting 6h at 90 DEG C
Phase Beckmann rearrangement legal system hexanolactam catalyst.
Embodiment 1
According to mass ratio will be 1 with 25wt%TPAOH solution according to the resulting extruded moulding catalyst sample of comparative example 1:
10 mixing, 170 DEG C of crystallization are for 24 hours.After separating, washing, by 60 DEG C of dryings of solid, a kind of gas phase Beckman is made in 450 DEG C of roasting 6h
Reset legal system hexanolactam catalyst.
Embodiment 2
According to mass ratio will be 1 with 25wt%TPAOH solution according to the resulting extruded moulding catalyst sample of comparative example 1:
10 mixing, 170 DEG C of crystallization 48h.After separating, washing, by 60 DEG C of dryings of solid, a kind of gas phase Beckman is made in 450 DEG C of roasting 6h
Reset legal system hexanolactam catalyst.
Embodiment 3
Embodiment 1,2 and comparative example 1,2 catalyst rearrangement reaction performances.
Cyclohexanone-Oxime Gas Phase Beckmann Rearrangement carries out in the stainless steel fixed bed reactors of internal diameter 6mm.By bar shaped
Catalyst powder is broken into 40-60mm size particles.0.2000g catalyst is taken to be fitted into reactor, catalyst bed loads up and down
The quartz sand of 1.000g 40-60 mesh, and held with silica wool.In carrier gas N2Flow velocity is in 20mL/min with 13.3 DEG C/min liter
Temperature keeps 1h, reaction temperature is then reduced to 370 DEG C, uses HPLC pressure pump by raw material for the ethyl alcohol of cyclohexanone oxime to 400 DEG C
Solution (30wt%) is reacted by fixed bed, and the mass space velocity of cyclohexanone oxime is 8h-1.Every 2h is cold using ice-water mixture
But gas-liquid separator collecting and sampling, every sub-sampling 10min.
Using chromatographic Cyclohexanone-Oxime Gas Phase Beckmann Rearrangement product.Capillary chromatographic column column length 50m
(OV1701), using hydrogen flame ionization detector.Pillar temperature programming condition: 150 DEG C of holding 10min, 25 DEG C/min are warming up to
225 DEG C, 10min is kept at this temperature.Temperature of vaporization chamber is 270 DEG C, and detector temperature is 280 DEG C.
The detection of cyclohexanone oxime (CHO) uses internal standard method, and internal standard solution is repefral, and calculating formula is as follows:
XCHO=(nc 0-nc)/nc 0× 100%
In formula, XCHOFor cyclohexanone oxime conversion ratio；nc 0And ncCyclohexanone oxime when respectively reaction starts and at the end of reaction
The amount of substance.The content of caprolactam is calculated using area normalization method after reaction, and solvent is not involved in integral.Reaction result is listed in table
1。
The different embodiment rearrangement reaction results of table 1
After S-1 molding, since the addition of silicon bonding causes its catalytic performance and stability to have certain decline.After forming
S-1 can significantly improve its catalytic performance and stability with the alkaline aqueous solution processing containing tetrapropyl cation.
Above-described embodiment is the preferred embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment
Limitation, it is other any without departing from the substitute mode that should be equivalent is changed made by the present invention, it is included in guarantor of the invention
Within the scope of shield.
Claims (7)
1. a kind of method for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, which is characterized in that this method is made
Modified MFI molecular sieve, detailed process are extruded mouldings after mixing containing MFI structure molecular sieve with bonding agent, extrusion aid, will be squeezed
Item catalyst after molding is handled with the alkaline aqueous solution containing tetrapropyl cation, is separated by solid-liquid separation, will be separated after the completion of processing
Solid drying and roasting obtain modified MFI molecular sieve, wherein bonding agent is silica solution, and extrusion aid is polyethylene glycol 400 and sesbania
Powder.
2. the method according to claim 1 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
It is, the alkaline aqueous solution containing tetrapropyl cation is TPAOH aqueous solution or TPABr and amine compound, hydramine
The mixture of the mixed aqueous solution of compound or two kinds of aqueous solutions.
3. the method according to claim 2 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
Be, the TPABr and amine compound, alcohol amine compound mixed aqueous solution in TPABr and amine compound, hydramine
The molar ratio of compound is 1:1:1.
4. the method according to claim 2 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
It is, the amine compound is ethylenediamine, and alcohol amine compound is ethanol amine.
5. the method according to claim 1 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
It is, the alkaline aqueous solution concentration containing tetrapropyl cation is 20 ~ 30wt%.
6. the method according to claim 1 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
It is, the alkaline aqueous solution dosage containing tetrapropyl cation is 5 ~ 20 times of dry extruded moulding catalyst weight.
7. the method according to claim 1 for improving molding MFI molecular sieve catalytic Beckmann rearrangement performance, feature
It is, when handling the catalyst of extruded moulding with the alkaline aqueous solution containing tetrapropyl cation, the temperature of processing is 120 ~ 170
DEG C, the time of the contact is 6 ~ 48h.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111790433A (en) * | 2020-07-03 | 2020-10-20 | 浙江恒澜科技有限公司 | Catalyst containing silicon molecular sieve with MFI topological structure, preparation method and application thereof, and gas phase Beckmann rearrangement reaction method |
| CN115337958A (en) * | 2022-07-07 | 2022-11-15 | 郑州大学 | Method for improving activity site of formed S-1 molecular sieve for catalyzing cyclohexanone oxime gas phase Beckmann rearrangement reaction |
| CN115739168A (en) * | 2022-12-21 | 2023-03-07 | 江苏扬农化工集团有限公司 | Composite molecular sieve and preparation method and application thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1600428A (en) * | 2003-09-28 | 2005-03-30 | 中国石油化工股份有限公司 | Method for preparing catalyst of containing MFI structured molecular sieve |
| CN101468319A (en) * | 2007-12-28 | 2009-07-01 | 中国石油化工股份有限公司 | Method for preparing catalyst containing molecular sieve of MFI structure |
| CN103464197A (en) * | 2013-09-25 | 2013-12-25 | 大连理工大学 | Propylene epoxidation catalyst, as well as preparation method and application thereof |
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2018
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1600428A (en) * | 2003-09-28 | 2005-03-30 | 中国石油化工股份有限公司 | Method for preparing catalyst of containing MFI structured molecular sieve |
| CN101468319A (en) * | 2007-12-28 | 2009-07-01 | 中国石油化工股份有限公司 | Method for preparing catalyst containing molecular sieve of MFI structure |
| CN103464197A (en) * | 2013-09-25 | 2013-12-25 | 大连理工大学 | Propylene epoxidation catalyst, as well as preparation method and application thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111790433A (en) * | 2020-07-03 | 2020-10-20 | 浙江恒澜科技有限公司 | Catalyst containing silicon molecular sieve with MFI topological structure, preparation method and application thereof, and gas phase Beckmann rearrangement reaction method |
| CN115337958A (en) * | 2022-07-07 | 2022-11-15 | 郑州大学 | Method for improving activity site of formed S-1 molecular sieve for catalyzing cyclohexanone oxime gas phase Beckmann rearrangement reaction |
| CN115337958B (en) * | 2022-07-07 | 2023-06-16 | 郑州大学 | Method for improving activity site of gas-phase Beckmann rearrangement reaction of cyclohexanone oxime catalyzed by formed S-1 molecular sieve |
| CN115739168A (en) * | 2022-12-21 | 2023-03-07 | 江苏扬农化工集团有限公司 | Composite molecular sieve and preparation method and application thereof |
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