CN105268472B - Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis - Google Patents
Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis Download PDFInfo
- Publication number
- CN105268472B CN105268472B CN201410314243.2A CN201410314243A CN105268472B CN 105268472 B CN105268472 B CN 105268472B CN 201410314243 A CN201410314243 A CN 201410314243A CN 105268472 B CN105268472 B CN 105268472B
- Authority
- CN
- China
- Prior art keywords
- shell
- zsm
- core
- silicalite
- symbiosis
- 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.)
- Active
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
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Silicates, Zeolites, And Molecular Sieves (AREA)
Abstract
The present invention relates to a kind of core-shell molecular sieves of ZSM 5/silicalite 1 of shell orientation extension symbiosis, mainly overcome to need to be repeated several times in conventional core-shell molecular sieve technology of preparing to grow and could form fine and close shell, the defects of shell raw material, template are using wasting be present, and the non-epitaxial symbiosis of shell, non-oriented phenomena such as growing and be uneven are still suffered from, cause shell bad mechanical strength, the activity of catalyst poor with stability.After the present invention is by the weak alkaline aqueous solution pretreatment to nuclear phase zeolitic material, the core-shell molecular sieve of the densification shell of symbiosis containing extension is made in shell Crystallization of Zeolite system and under suitable reaction condition, it is efficiently used for aromatic hydrocarbons selective disproportionation, shape-selective transalkylation and shape-selective methylation reaction, the a large amount of useful paraxylene isomers of generation, pass through core, the allotment of shell composition, the catalyst has catalytic activity height, aromatic hydrocarbons treating capacity is big, integrated machine intensity is high, it is few using loss, the characteristics of para-xylene product is selectively high, more efficiently it can be used in industrial production.
Description
Technical field
The present invention relates to a kind of ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis.
Background technology
Traditional toluene disproportionation or alkylation reaction technique, the ZSM-5 molecular sieve catalyst of mesopore duct (10 membered oxygen rings)
On obtained product be generally only thermodynamical equilibrium composition mixed xylenes, the para-isomer of high added value only accounts for therein
Sub-fraction.Long-term for not possessing in the modification of selective molecular sieve outer surface research, find core-shell molecular sieve for core
The outer surface modification of phase molecule sieve, it is intended to keep molecular sieve high stability and catalytic activity to greatest extent.silicalite-1
It is that the pure silicon dioxide with MFI skeleton structures identical with ZSM-5 forms, is connected what is formed by silicon-oxy tetrahedron, surface silicon hydroxyl
Base defect is less, and has excellent hydrophobicity, industrially with important technology application value.
On the basis of the heterogeneous improving performance of core-shell material, core-shell molecular sieve because its ingredient sieve specific to uniformly in
Outer surface and regular nano pore structure, there is larger specific surface area, stronger Acidity, and specific reactant, product
The shape-selective reaction channel of molecule, is widely used in petroleum refining and process, such as catalytic reforming, catalytic cracking, accordance
The catalytic reactions such as change, isomerization and toluene disproportionation.On the basis of the high-temperature hydrothermal stability of nuclear phase molecular sieve is ensured, by changing
Different shells can be obtained by becoming the synthetic parameters such as the composition, crystallization temperature, crystallization time of shell growth solution.Mobil companies
Researcher coupled the ZSM-5 of high activity and the silicalite-1 of high selectivity, anacidity first in patent US4088605
Property position shell effectively inhibits the generation of surface side reaction (non-shape-selective cracking or isomerization reaction) from source, and significantly carries
The selectivity of reactant and product is risen.But for a long time, the either growth in situ or diauxic growth of shell, is concentrated on point
Son sieve surface is uniform but the research of non-oriented growth, can not play the same of shell molecular sieve mass-and heat-transfer effect to greatest extent
When, the waste of synthesis material is unavoidably caused, and the defects of tedious process be present.
In the research of shell growth, silicon source and its parent solution solvents environment all have a significant impact to silicalite-1, silicon
Also there is considerable influence in source not only to Crystallization Dynamics to crystallization thermodynamics, and in crystallization process, the dissolving of silicon source is hydro-thermal
The first step of synthesis, and be rate determining step.In addition, influence of the solvent to molecular screen membrane class Material growth is also that act foot is light
[Micropor.Mesopor.Mater., 2007,103, the 296] organic solvents such as weight, Wee are for suppressing nucleation, effectively facilitating shell
Layer extension symbiosis has obvious inducing action, as the hydrolysis of tetraethyl orthosilicate may be such that crystallization mother liquor has a certain amount of second
Alcohol.Lai etc. [Science, 2003,300:456-460] to be pointed out when studying molecular screen membrane, oriented growth molecular sieve is with height
While stability, high strength dense are formed, the preparation process of catalyst is enormously simplify, greatlys save synthesis material and bar
Part cost.[the Appl Catal A such as Gora:General,2007,325:316-321] find pre- place of the butyl titanate to nuclear phase
Reason, easily lures the aligned growth in nuclear phase outer surface of shell into, but and not deployed shell structurre orientation research, and this kind of method
Coating material used and the price of macromolecular template agent costly, exist on the premise of it can not realize recycling
The defects of being difficult to industrialize extensive use.Oriented growth is applied to core-shell molecular sieve by hole etc. [CN103121687A]
Study on the synthesis, the profiling results characterized from sample powder X-ray diffraction can quantify the b oriented growth degree of shell, I(101)Spread out
Penetrate the random growth that peak corresponds to MFI, I(020)Diffraction maximum corresponds to MFI b oriented growths, i.e. the b oriented growths of shell can use
Growth index I(020)/I(101)This concept quantitatively describes, the b of MFI 3 D pore canals orientation shell structurre so that reactant and
The diffusion rate of product greatly improves, and the stability of reaction rate and catalyst will also increase therewith, but patent content is related to system
Standby process is cumbersome, and shell compactness and uniformity need to be further improved, and cost is larger and a large amount of waves of crystallization raw material be present
Take.In addition, the original position of document report and diauxic growth (crystal seeds of such as preset different silica alumina ratios [J Catal, 2006,243:389-
394], change in advance nuclear phase outer surface electronegativity [Chem Mater, 2006,18:4959-4966] etc.) method is difficult
To the shell structurre of b orientations.Okubo etc. [Angew.Chem.Int.Ed., 2001,40:1069] different molecular is proposed first
Sieve type, only microcosmic crystal structure completely or approximately could occur between identical molecular sieve type between molecular sieve it is heterogeneous outside
Prolong symbiosis.Herein under theoretical guide, Li etc. [Micropor.Mesopor.Mater., 2005,78,1] is had found by surface acid
Reason, is advantageous to the formation of monocrystalline shell core-shell molecular sieve, nuclear phase surface defect caused by acid treatment (can by acid reaction variables and
Process control), difference coverage oriented growth shell structurre is induced, this method step is simple, it is not necessary to stick crystal seed in advance, have
There are a certain Objective and operable scope, the specific shell structurre of shell, effective coverage and thickness are not directed in text
The concepts such as uniformity.
At present in the research of core-shell molecular sieve, although the influence factor such as growth conditions and nuclear phase surface nature with regard to shell
Relatively broad research is expanded, is grown for cost-efficiently shell, still lacks regulation and control consciousness and lacks effectively to regulate and control
Means, the concept of the symbiosis of molecular sieve extension and oriented growth is used for reference, realize the control freely and regulation and control synthesis of shell structurre, obtain
The core-shell molecular sieve of the fine and close orientation shell of single crystal-like tool, is a brand-new research direction, and the covering of shell will be finer and close,
And thickness is more uniform.Research finds, weak base aqueous solution is not to being calcined the Passivation Treatment of nuclear phase outer surface, compared with surface defect and electricity
The method for pretreating such as negativity modification, operation purpose is stronger, and step is simple, and is orientated the effect of extension symbiosis particularly for shell b
Substantially.The defects of the invention aims to overcome shell intensity difference in the prior art, extension symbiosis oriented growth shell
Core-shell molecular sieve pattern is more integrated and shell is finer and close, and duct is more regular in order, is being obviously improved catalytic mechanical
While intensity and reactivity worth, reaction loss and the failure probability of catalyst are reduced, and enormously simplify preparation method and section
Raw material is saved.
The content of the invention
One of technical problems to be solved by the invention be in order to overcome needed in conventional core-shell molecular sieve technology of preparing it is more
Secondary repeated growth could form fine and close shell, the defects of shell raw material, template are using wasting be present.A kind of new shell is provided
The preparation method of extension symbiosis ZSM-5/silicalite-1 core-shell molecular sieves is orientated, passes through the alkalescent to nuclear phase zeolitic material
The aqueous solution pre-processes, and synthesis under certain condition obtains the core-shell molecular sieve of the densification shell of symbiosis containing extension, greatly reduces shell
Layer raw material, the usage amount of template, are allocated by the composition of nucleocapsid, can efficiently, controllably synthesis of molecular sieve shell.
The two of the technical problems to be solved by the invention are shell be present to overcome in conventional core-shell molecular sieve technology of preparing
The non-epitaxial symbiosis of layer, non-oriented phenomena such as growing and be uneven, cause shell bad mechanical strength, the activity of catalyst and stability
Difference.This method is in the extension symbiosis of nuclear phase ZSM-5 surfaces and the uniform silicalite-1 shells of oriented growth, shell mechanical strength
Good, catalyst activity is good with stability, solves the items in the catalytic effect and catalyst preparation process of core-shell molecular sieve
The matching problem of synthetic parameters.
The three of the technical problems to be solved by the invention are to provide a kind of ZSM-5/ of effectively increasing yield of p-xylene
Silicalite-1 core-shell molecular sieve catalyst, aromatic hydrocarbons selective disproportionation, form selected methylation reaction can be effectively applied to, for height
The industrial production of selective para-xylene product.The catalyst has catalytic activity high, and aromatic hydrocarbons treating capacity is big, and integrated machine is strong
The characteristics of degree is high, few using loss, and para-xylene product is selectively high.
To solve one of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：A kind of shell is orientated extension symbiosis
ZSM-5/silicalite-1 core-shell molecular sieves, nuclear phase ZSM-5, shell is orientation extension symbiosis silicalite-1；Its
In, the mass ratio of nuclear phase and shell is 0.5~15:1, shell silicalite-1 coverage are more than the extension of 80%, b orientations
Coupled growth index is more than 7.
In above-mentioned technical proposal, a kind of ZSM-5/silicalite-1 nucleocapsid molecules of shell orientation extension symbiosis are synthesized
Sieve, it is characterised in that the mass ratio of nuclear phase and shell is 1~10:1, shell silicalite-1 coverage take more than 83%, b
To growth index be more than 7.3, SiO2/Al2O3Mol ratio is 20~300, and particle diameter is 0.1~20 micron.
In above-mentioned technical proposal, shell is extension symbiosis densification silicalite-1；Wherein shell silicalite-1 is thick
Spend for 0.2~100nm, SiO2/Al2O3Mol ratio is 100~∞,.
To solve the two of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：Shell orientation extension symbiosis
The preparation method of ZSM-5/silicalite-1 core-shell molecular sieves comprises the following steps：
(a) the nuclear phase zeolite crystal outer surface pretreatment containing template is not calcined：In 20 DEG C~120 DEG C treatment temperatures
Under, it is placed in the aqueous solution of 0.01~0.5 mol/L ammonia, urea, hexamethylenetetramine, metal carbonate or alkali metal bicarbonate salt
In, handle 0.5~24 hour, ammonia, metal carbonate or alkali metal bicarbonate salt provide OH by hydrolyzing-Ion, urea decomposing shape
Ammonification and CO2, then decomposing shape ammonification and formaldehyde have sustained release alkalescent to methenamine, treat crystal grain outer surface acidity position and treatment fluid
Fully after contact, filter and at a temperature of 20 DEG C~120 DEG C to dry；
(b) preparation of shell crystallization mother liquor：Crystallization liquid is made up of silicon source, template T, organic solvent O and deionized water, group
Into mol ratio T/SiO2=0.02~1, H2O/SiO2=6~150, O/SiO2=0.001~2, wherein, template T is selected from 4 third
At least one in base ammonium hydroxide, 4-propyl bromide, Tri-n-Propylamine, cyclohexylamine, ammonium fluoride, ocratation or ammonium fluosilicate
Kind, organic solvent O is selected from least one of methanol, ethanol, ethylene glycol, glycerine, isobutanol or dimethyl furan, and shell is brilliant
Change at a temperature of mother liquor is placed in 20 DEG C~80 DEG C and be aged 0.5~6 hour；
(c) (a), the pretreated nuclear phase ZSM-5 of (b) step are mixed with shell crystallization mother liquor, wherein nuclear phase addition
SiO is scaled with the silicon source in mother liquor2Mass ratio be 1~50:1, crystallization at a temperature of both are placed in 80 DEG C~250 DEG C after mixing
0.5~240 hour, crystallization was exchanged at least once and in 20 DEG C~120 DEG C temperature after terminating through filtering, washing to pH value=7, ammonium
Lower dry of degree obtains the ZSM-5/silicalite-1 cores of shell orientation extension symbiosis after 300 DEG C~600 DEG C roasting temperatures
Shell molecular sieve.
In above-mentioned technical proposal, the concentration of weak alkaline aqueous solution is 0.05~0.1 mol/L in (a) step；(b) step
Used in silicon source at least one of for tetraethyl orthosilicate, white carbon, Ludox, silica or atlapulgite；(c) step
The butt quality ratio of middle nuclear phase and shell is 2~10:1, shell crystallization crystallization 3~72 hours at 120~180 DEG C.
To solve the three of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：The side of three productions paraxylene
Method, it is respectively：It is 290~460 DEG C, 1.0~2.5MPa of reaction pressure in reaction temperature using pure toluene as raw material, weight space velocity
For 2.0~5.0h-1, hydrogen-hydrocarbon ratio is the shape-selective disproportionation reaction under the conditions of 1.0~3.0, and reaction generation includes the production of paraxylene
Thing.It is 280~420 DEG C in reaction temperature using benzene, toluene, methanol, trimethylbenzene, durene, penta-methyl benzene as raw material, reaction pressure
0.1~3.5MPa, weight space velocity are 1.0~4.5h-1, hydrogen-hydrocarbon ratio is the shape-selective transalkylation reaction under the conditions of 1.0~3.0；With
Using benzene, toluene, methanol as raw material, reaction temperature be 350~650 DEG C, 0~3.0MPa of reaction pressure, weight space velocity be 1.0~
45h-1, hydrogen-hydrocarbon ratio be 1.0~3.0 under the conditions of shape-selective methylation reaction, raw material respectively by with the bed containing above-mentioned catalyst
Contact, reaction generation PX products.
The present invention is not calcined the nuclear phase ZSM-5 molecular sieve containing template by weak base aqueous solution pretreatment, is passivated outside crystal grain
The acidic site on surface, the uniform micro desiliconization of nuclear phase molecular sieve outer surface is caused to a certain extent, can be by pre-processing waste liquid
ICP detection and analysis, the preprocess method is particularly suitable for use in compared with the nuclear phase molecular sieve of high silica alumina ratio.The innovative point of the technology exists
In preprocess method is aided with the shell growth mother liquid containing organic solvent, and these equally distributed blunt positions can induce and be beneficial to
The effect of some single crystal face growth, ensureing shell oriented growth and do not destroying the base of nuclear phase molecular sieve outer surface skeleton structure
On plinth, effectively induce and strengthen ability of the shell molecular sieve in passivation outer surface extension symbiosis, can be with by adjusting synthesis condition
Neatly regulate and control the orientation extension symbiosis of shell.In addition, weakly alkaline separate sources used herein and its concentration fine setting tool
There is certain independence, be not related to or directly affect the growth conditions parameter of shell nuclear phase crystal grain outer surface after the pre-treatment, therefore
It enormously simplify the orientation extension symbiosis control of shell.Obtained core-shell molecular sieve is synthesized using the technical method of the present invention, is had
There are the fine and close orientation silicalite-1 shells of extension symbiosis of Single crystal type aligned growth, this method does not need conventional core-shell molecular sieve
Stick the complex processes such as crystal seed in advance in building-up process, operating procedure is simple, and with shell structurre taxis is strong, effect is bright
The advantages of aobvious, while catalytic performance is lifted, it enormously simplify preparation method and saved raw material.ZSM-5/
Silicalite-1 core and shell are MFI structure, for the production field of paraxylene, applied to selective disproportionation, shape-selective
In transalkylation and shape-selective methylation reaction, PX selectivity of product is improved.
Brief description of the drawings
Fig. 1：The TEM figures of shell orientation extension symbiosis ZSM-5/silicalite-1 core-shell type molecular sieve materials.
Below by embodiment, the present invention is further elaborated.
Embodiment
【Embodiment 1】
360 grams of Ludox (wt.40%) are dissolved in 200 grams of water, are configured to solution A；7 grams of aluminum sulfate are dissolved in 100 grams
In water, solution B is configured to；3 grams of potassium sulfates are dissolved in 240 grams of water, are configured to solution C.Solution B is slowly added dropwise to solution A
In, it is sufficiently stirred, adds solution C, in 170 DEG C of crystallization 2 days, filtering, low temperature drying obtained big crystalline substance for the reactant mixture of formation
The nuclear phase ZSM-5 molecular sieve of grain.
320 grams of ZSM-5 originals powder not being calcined mole silica alumina ratio 100, are added to 0.05 mol/L as nuclear phase molecular sieve
Aqueous solution of urea in, be warming up under stirring 80 DEG C and keep 2 hours, filter simultaneously in 120 DEG C of air atmospheres dry
Obtain the ZSM-5 nuclear phase molecular sieves after outer surface reason.
120 grams of white carbons, 10 grams of ocratations, 800 grams of tetraethyl ammonium hydroxides and 6000 milliliters of water, uniform stirring plastic
Silicalite-1 shell crystallization mother liquors are obtained, are slowly added to the ZSM-5 nuclear phases point after above-mentioned weak base Passivation Treatment while stirring
Son sieve powder, stirring ageing add 500 grams of glycerine after 2 hours, and the mixed system moves into rapidly the stainless of polytetrafluoroethyllining lining
In steel sleeve crystallizing kettle, it is put in static crystallization in 160 DEG C of baking ovens and takes out for 30 hours, point that filtering, washing, drying, roasting obtain
Son sieve sample is designated as BS1.The b oriented growths index that XRD spectrum characterizes display BS1 sample shells is 18；The shape at TEM nucleocapsids interface
Looks, structural characterization result show that the coverage of BS1 sample shells is more than 99.9%, b and is orientated shell in nuclear phase ZSM-5 crystal grain appearances
Face is orderly, equably arranged type extension symbiosis, and outer surface of the XPS elementary analyses core-shell molecular sieve in detection range is averagely rubbed
Your silica alumina ratio is more than 400, preferably confirms class single crystal epitaxial symbiosis of the b orientation silicalite-1 in ZSM-5 crystal grain outer surface.
【Embodiment 2】
600 grams of waterglass are dissolved in 900 grams of water, are configured to solution A；25 grams of aluminum sulfate are dissolved in 300 grams of water, configured
Into solution B；20 grams of sodium sulphate are dissolved in 200 grams of water, are configured to solution C.Solution B is slowly added dropwise in solution A, fully stirred
Mix, add solution C, in 140 DEG C of crystallization 4 days, filtering, low temperature drying obtained the nuclear phase of little crystal grain for the reactant mixture of formation
ZSM-5 molecular sieve.
40 grams of ZSM-5 originals powder not being calcined are as nuclear phase molecular sieve, mole silica alumina ratio 40, the HMT of 0.05 mol/L of addition
In the aqueous solution, 90 DEG C are warming up under stirring and is kept for 3 hours, filtering and the drying to obtain in 120 DEG C of air atmospheres
ZSM-5 nuclear phase molecular sieves after the processing of outer surface.
35 grams of TEOS, 6 grams of TPABr, 180 milliliters of water, uniform stirring plastic obtain silicalite-1 shell crystallization mother liquors,
The ZSM-5 nuclear phase molecular sieve powder after above-mentioned processing is slowly added to while stirring, and stirring ageing adds 10 grams of ethanol after 1 hour, should
Mixed system is moved into rapidly in the stainless steel outer sleeve crystallizing kettle of polytetrafluoroethyllining lining, is put in static crystallization 24 in 180 DEG C of baking ovens
Hour take out, filtering, washing, drying, the obtained sieve sample of roasting are designated as BS2.XRD spectrum, which characterizes, shows BS2 sample shells
The b oriented growths index of layer is 13；The pattern at SEM nucleocapsids interface, structural characterization result show that the coverage of BS2 sample shells is big
In 98%, in nuclear phase ZSM-5 crystal grain outer surface, in order, equably continuous growth, the XPS elementary analyses core-shell molecular sieve exist shell
Outer surface molar average silica alumina ratio in detection range is more than 400, and gained is polycrystalline silicalite-1 cladding ZSM-5 crystal grain
The core-shell molecular sieve of outer surface.
【Comparative example 1】
After the big crystal grain ZSM-5 original powder synthesized with embodiment 1 does same pretreatment, as nuclear phase molecular sieve.
43 grams of white carbons are dissolved in 560 grams of water, are configured to solution A；By 100 grams of tetraethyl ammonium hydroxide solution (25%
Concentration) it is dissolved in 200 grams of water, it is configured to solution B.Solution A, B are sufficiently stirred mixing, it is in situ to form silicalite-1 shells
Growth mother liquid, 50 grams of nuclear phase big crystal grain ZSM-5 molecular sieves are added, molecular sieve more difficult to filter is obtained within 48 hours in 180 DEG C of crystallization
Product, through SEM/TEM patterns, characterization of crystalline phase, although the mean coverage of shell reaches 87%, occur in product compared with polydispersion
Independent growths 100nm or so little crystal grain, shell oriented growth index only have 0.2.
【Comparative example 2】
With embodiment it is 2-in-1 into small-grain ZSM-5 original powder do not pre-process, as nuclear phase molecular sieve.
150 grams of tetraethyl orthosilicates are dissolved in 560 grams of water, are configured to solution A；By 72 grams of tetraethylammonium bromides, 3 grams of fluorine
Change ammonia to be dissolved in 100 grams of water, be configured to solution B.Solution A, B are sufficiently stirred mixing, it is in situ to form silicalite-1 shells
Growth mother liquid, 90 grams of nuclear phase ZSM-5 molecular sieve with small crystal grains and 30 grams of isobutanols are added, in 120 DEG C of crystallization 72 hours, obtained boiling
Stone molecular sieve product, is characterized through SEM, and more twin particle is formed in product, causes cylindrical or strip crystal grain stick
Growth, shell covering is not observed in nuclear phase crystal grain outer surface.
【Embodiment 3~13】Embodiment 3~13 is with the continuous raw material proportioning of table 1, table 1 and synthetic material, by the class of embodiment 1
Core-shell molecular sieve BS3~13 for the orientation extension symbiosis silicalite-1 shells containing b for synthesizing to obtain like condition, method and step,
It is continuous to refer to table 1, table 1.
Table 1
Table 1 is continuous
【Embodiment 14-19】
Embodiment 14~19 is with shell orientation extension symbiosis ZSM-5/silicalite-1 core-shell type molecular sieve samples BS-
1st, BS-2 is catalyst, is respectively used to the production of paraxylene.It the results are shown in Table 2.
Table 2
Claims (10)
1. a kind of ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis, nuclear phase ZSM-5, shell is to take
To extension symbiosis silicalite-1；Wherein, the mass ratio of nuclear phase and shell is 0.5~15:1, shell silicalite-1's
The extension coupled growth index that coverage is more than 80%, b orientations is more than 7；
Wherein, the preparation method of the ZSM-5/silicalite-1 core-shell molecular sieves of described shell orientation extension symbiosis, including
Following steps：
(a) 0.01~0.5 mol/L ammonia, urea, hexamethylenetetramine, metal are placed in containing the nuclear phase ZSM-5 for not being calcined template
It is pre- in the alkalescent at a temperature of 20~120 DEG C or sustained release weakly alkaline solution in carbonate or the aqueous solution of alkali metal bicarbonate salt
Handle crystal grain outer surface；
(b) preparation of shell crystallization mother liquor：Crystallization liquid is made up of silicon source, template T, organic solvent O and deionized water, and composition rubs
You compare T/SiO2=0.02~1, H2O/SiO2=6~150, O/SiO2=0.001~2, wherein, template T is selected from tetrapropyl hydrogen
At least one of amine-oxides, 4-propyl bromide, Tri-n-Propylamine, cyclohexylamine, ammonium fluoride, ocratation or ammonium fluosilicate, have
Solvent O is selected from least one of methanol, ethanol, ethylene glycol, glycerine, isobutanol or dimethyl furan, and shell crystallization is female
Liquid is aged 0.5~6 hour at a temperature of being placed in 20~80 DEG C；
(c) pretreated nuclear phase ZSM-5 in (a) step is obtained into shell crystallization mother liquor with (b) step to be mixed, its center
The amount of being added to is scaled SiO with the silicon source in mother liquor2Mass ratio be 1~50:1, both are placed in 80~250 DEG C of temperature after mixing
Lower crystallization 0.5~240 hour, filtered after crystallization, wash to pH value=7, ammonium exchange and at least once, and done at 20~120 DEG C
It is dry to obtain core-shell molecular sieve after roasting at 300~600 DEG C.
2. the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 1, it is special
Sign is that the mass ratio of nuclear phase and shell is 1~10:1, shell silicalite-1 coverage are more than the life of 83%, b orientations
Long index is more than 7.3.
3. the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 1, it is special
Sign is nuclear phase molecular sieve ZSM-5 SiO2/Al2O3Mol ratio is 20~300, and particle diameter is 0.1~20 micron.
4. the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 1, it is special
Sign is shell silicalite-1 SiO2/Al2O3Mol ratio is 100~∞, and thickness is 0.2~100nm.
5. the preparation of the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 1
Method, comprise the following steps：
(a) 0.01~0.5 mol/L ammonia, urea, hexamethylenetetramine, metal are placed in containing the nuclear phase ZSM-5 for not being calcined template
It is pre- in the alkalescent at a temperature of 20~120 DEG C or sustained release weakly alkaline solution in carbonate or the aqueous solution of alkali metal bicarbonate salt
Handle crystal grain outer surface；
(b) preparation of shell crystallization mother liquor：Crystallization liquid is made up of silicon source, template T, organic solvent O and deionized water, and composition rubs
You compare T/SiO2=0.02~1, H2O/SiO2=6~150, O/SiO2=0.001~2, wherein, template T is selected from tetrapropyl hydrogen
At least one of amine-oxides, 4-propyl bromide, Tri-n-Propylamine, cyclohexylamine, ammonium fluoride, ocratation or ammonium fluosilicate, have
Solvent O is selected from least one of methanol, ethanol, ethylene glycol, glycerine, isobutanol or dimethyl furan, and shell crystallization is female
Liquid is aged 0.5~6 hour at a temperature of being placed in 20~80 DEG C；
(c) pretreated nuclear phase ZSM-5 in (a) step is obtained into shell crystallization mother liquor with (b) step to be mixed, its center
The amount of being added to is scaled SiO with the silicon source in mother liquor2Mass ratio be 1~50:1, both are placed in 80~250 DEG C of temperature after mixing
Lower crystallization 0.5~240 hour, filtered after crystallization, wash to pH value=7, ammonium exchange and at least once, and done at 20~120 DEG C
It is dry to obtain core-shell molecular sieve after roasting at 300~600 DEG C.
6. the preparation of the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 5
Method, it is characterised in that pre-processed in (a) step to nuclear phase outer surface with weak alkaline aqueous solution, treatment fluid concentration is 0.05
~0.1 mol/L.
7. the preparation of the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 5
Method, it is characterised in that the silicon source used in (b) step is tetraethyl orthosilicate, white carbon, Ludox, silica or activity are white
At least one of soil.
8. the preparation of the ZSM-5/silicalite-1 core-shell molecular sieves of shell orientation extension symbiosis according to claim 5
Method, it is characterised in that in (c) step center, shell butt quality ratio be 2~10:1, shell crystallization crystallization at 120~180 DEG C
3~72 hours.
A kind of 9. method for producing paraxylene, using the core-shell molecular sieve described in Claims 1 to 4 any one as catalysis
Agent, using pure toluene as raw material, reaction temperature be 290~460 DEG C, 1.0~2.5MPa of reaction pressure, weight space velocity be 2.0~
5.0h-1, hydrogen-hydrocarbon ratio be 1.0~3.0 under conditions of contacted with catalyst, carry out shape-selective disproportionation reaction, reaction generation include to two
The product of toluene.
10. a kind of method for producing paraxylene, it is used as and is urged using the core-shell molecular sieve described in Claims 1 to 4 any one
Agent, it is 280~420 DEG C in reaction temperature using benzene, toluene, methanol, trimethylbenzene, durene, penta-methyl benzene as raw material, reaction pressure
0.1~3.5MPa of power, weight space velocity are 1.0~4.5h-1, hydrogen-hydrocarbon ratio be 1.0~3.0 under conditions of contacted with catalyst, carry out
Shape-selective transalkylation reaction, reaction generation include the product of paraxylene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410314243.2A CN105268472B (en) | 2014-07-03 | 2014-07-03 | Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410314243.2A CN105268472B (en) | 2014-07-03 | 2014-07-03 | Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105268472A CN105268472A (en) | 2016-01-27 |
| CN105268472B true CN105268472B (en) | 2018-02-13 |
Family
ID=55138825
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410314243.2A Active CN105268472B (en) | 2014-07-03 | 2014-07-03 | Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105268472B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105800636A (en) * | 2016-05-11 | 2016-07-27 | 浙江大学 | Method for preparing MFI type molecular sieve through epitaxial growth |
| CN107758690A (en) * | 2016-08-23 | 2018-03-06 | 中国石油化工股份有限公司 | The method for improving the microwave synthesis MFI/MFI core-shell molecular sieves of shell coverage |
| CN107930677B (en) * | 2016-10-12 | 2020-10-27 | 神华集团有限责任公司 | Modified ZSM-5 catalyst for alkylation reaction, preparation method and application thereof, and preparation method of p-xylene |
| CN109569701B (en) * | 2017-09-28 | 2021-08-06 | 中国石油化工股份有限公司 | Preparation method of ZSM-5/Silicalite-1 core/shell molecular sieve |
| CN109590019A (en) * | 2017-09-30 | 2019-04-09 | 株式会社模范 | Catalyst and its preparation and the application of paraxylene are directly prepared for synthesis gas |
| CN107670687A (en) * | 2017-10-10 | 2018-02-09 | 中国石油大学(华东) | Molecular sieves of 5@Silicalite of nano crystal ZSM 1 of core shell structure and preparation method thereof |
| CN112777609B (en) * | 2019-11-08 | 2022-10-11 | 国家能源投资集团有限责任公司 | Composite twin crystal ZSM-5 molecular sieve, and preparation method and application thereof |
| CN111569935B (en) * | 2020-05-22 | 2023-12-12 | 中国海洋石油集团有限公司 | Catalyst for preparing paraxylene and preparation method and application thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101602010A (en) * | 2009-07-08 | 2009-12-16 | 中国科学院上海有机化学研究所 | Molecular sieve catalyst, preparation method and the application in crylic acid preparation by lactic acid dehydration thereof |
| CN102311124A (en) * | 2010-07-07 | 2012-01-11 | 中国石油化工股份有限公司 | Method for preparing Silicalite-1/ZSM-5 composite molecular sieve |
| CN102658197A (en) * | 2012-05-16 | 2012-09-12 | 浙江师范大学 | Catalyst for normal paraffin hydroisomerization reaction and preparation method as well as application thereof |
| CN103121687A (en) * | 2011-11-18 | 2013-05-29 | 中国石油化工股份有限公司 | Nuclear shell molecular sieve SRZ-1 and preparation method thereof |
| CN103539152A (en) * | 2012-07-12 | 2014-01-29 | 中国石油化工股份有限公司 | Silicon modified core-shell molecular sieve and preparation method thereof |
-
2014
- 2014-07-03 CN CN201410314243.2A patent/CN105268472B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101602010A (en) * | 2009-07-08 | 2009-12-16 | 中国科学院上海有机化学研究所 | Molecular sieve catalyst, preparation method and the application in crylic acid preparation by lactic acid dehydration thereof |
| CN102311124A (en) * | 2010-07-07 | 2012-01-11 | 中国石油化工股份有限公司 | Method for preparing Silicalite-1/ZSM-5 composite molecular sieve |
| CN103121687A (en) * | 2011-11-18 | 2013-05-29 | 中国石油化工股份有限公司 | Nuclear shell molecular sieve SRZ-1 and preparation method thereof |
| CN102658197A (en) * | 2012-05-16 | 2012-09-12 | 浙江师范大学 | Catalyst for normal paraffin hydroisomerization reaction and preparation method as well as application thereof |
| CN103539152A (en) * | 2012-07-12 | 2014-01-29 | 中国石油化工股份有限公司 | Silicon modified core-shell molecular sieve and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| Alikaline treatment of template containing zeolites:Introduceing mesoporosity while preserving acidity;Adri N.C.van laak等;《Catalysis Today》;20110106;第168卷;全文 * |
| 核壳型沸石分子筛的合成、表征与应用;孔德金等;《化学通报》;20081231(第4期);全文 * |
| 碱处理技术制备不同层级结构沸石研究进展;魏月华等;《化学工业与工程技术》;20131231;第34卷(第6期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105268472A (en) | 2016-01-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105268472B (en) | Shell is orientated the core-shell molecular sieves of ZSM 5/silicalite 1 of extension symbiosis | |
| Javdani et al. | Nano-sized ZSM-5 zeolite synthesized via seeding technique for methanol conversions: A review | |
| CN104150507A (en) | One-step preparation method of empty shell type small grain ZSM-5 molecular sieve | |
| CN106904636B (en) | The SSZ-13 molecular sieve and its synthetic method of a kind of multi-stage artery structure with micropore-mesopore and application | |
| Zhang et al. | Facile fabrication of mesopore-containing ZSM-5 zeolite from spent zeolite catalyst for methanol to propylene reaction | |
| CN103301877B (en) | A kind of preparation method for methanol height selectively producing propene EU-1 molecular sieve catalyst | |
| CN105498826B (en) | ZSM-11/Silicalite-2 core-shell molecular sieves of fine and close shell and preparation method thereof | |
| CN105523569A (en) | Lamellar ZSM-5 molecular sieve and synthesis method thereof | |
| Han et al. | Fast synthesis of submicron ZSM-5 zeolite from leached illite clay using a seed-assisted method | |
| CN109174174A (en) | A kind of HZSM-5/SAPO-5 core-shell molecular sieve and its preparation method and application | |
| US11434183B2 (en) | Catalyst for preparing ethylbenzene from ethanol and benzene, preparation therefor and use thereof | |
| CN104192859B (en) | A kind of Fast back-projection algorithm method of the molecular sieve of fine grain ZSM-5 5 | |
| CN103121687A (en) | Nuclear shell molecular sieve SRZ-1 and preparation method thereof | |
| CN105293519A (en) | Synthesis method of ZSM-5/Y composite molecular sieve without using template | |
| CN102824923A (en) | Catalyst for synthesizing ethylbenzene by liquid phase method and preparation and application thereof | |
| CN107777697B (en) | Y-type molecular sieve and preparation method thereof | |
| CN106185978B (en) | A kind of synthetic method of the high silicon b orientations nanometer sheets of ZSM 5 | |
| CN107285339B (en) | High-silicon ZSM-5 molecular sieve and preparation method and application thereof | |
| US20180029894A1 (en) | Preparation method for beta zeolite | |
| Sun et al. | Ultrafast green synthesis of sub-micron Silicalite-1 zeolites by a grinding method | |
| CN105293520A (en) | Synthesis method for ZSM-5 molecular sieve of special morphology | |
| CN109502605A (en) | A kind of preparation method of multi-stage porous ZSM-11 molecular sieve | |
| CN107814393A (en) | A kind of method of rapid crystallization synthesis EMT molecular sieves | |
| CN107649172B (en) | Preparation method of catalyst for preparing p-xylene through toluene alkylation | |
| CN114100675B (en) | Preparation method of boron-containing molecular sieve and application of molecular sieve in butene double bond isomerization reaction |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |