CN101402022A - Novel methods for producing type A molecular sieve film in current system - Google Patents
Novel methods for producing type A molecular sieve film in current system Download PDFInfo
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- CN101402022A CN101402022A CNA200710049348XA CN200710049348A CN101402022A CN 101402022 A CN101402022 A CN 101402022A CN A200710049348X A CNA200710049348X A CN A200710049348XA CN 200710049348 A CN200710049348 A CN 200710049348A CN 101402022 A CN101402022 A CN 101402022A
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Abstract
The invention provides a novel method for preparing an A-type molecular sieve membrane, which adopts preparation of the molecular sieve membrane in a flow system. The method comprises the following steps: a silicon source, an aluminum source, an alkali source and deionized water are prepared into precursor sol of A-type molecular sieve according to certain proportion first; a vector membrane tube which is precoated with A-type molecular sieve crystal seeds is fixed inside a synthesis reactor; the molecular sieve precursor sol which is heated to a given temperature is conveyed into the synthesis reactor through a slurry pump, and the precursor sol is driven to flow and circulate on the surface of an outer membrane of the vector membrane tube; and the A-type molecular sieve membrane can be obtained after flowing, circulating and crystallization for a definite time at the given temperature. The preparation method provided by the invention has the advantages that the preparation method can basically solve the problem of concentration gradient during the synthetic process of he molecular sieve, is favorable to the preparation of the uniform, continuous and compact molecular sieve membrane with superior separation performance, and is particularly suitable for preparing the molecular sieve membrane for industrial application.
Description
Technical field
The invention provides the new method of preparation A type molecular sieve film in a kind of current system, belong to the technical field of inorganic material film preparation.
Background technology
Infiltration evaporation (Pervaporation is called for short PV) is a kind of new membrane isolation technics, and it is the new technology of a kind of high efficiency, low energy consumption, small investment.Its separation principle is not subjected to the restriction of thermodynamical equilibrium, depends primarily on the interaction between film and the penetrant component, is particularly suitable for that the way of distillation is difficult to separate or the separation of indissociable nearly boiling point, constant boiling point mixture and isomer.Separate with traditional rectification method and to compare, the infiltration evaporation membrane separation process can energy-conservation 1/2～1/3, operating cost is 50% of traditional rectification method technology, and can avoid product and environmental pollution, have significantly economically separating of organic matter and organic mixture removing in dehydration of organic solvent, the water, in the environmental protection and technical advantage.Have broad application prospects and market potential at industrial circles such as petrochemical industry, medicine, food, environmental protection, fine chemicals, be acknowledged as 21st century one of the most promising new and high technology.
Aspect the dehydration of organic solvent membrane material, the most ripe, most widely used at present is polyvinyl alcohol/polyacrylonitrile compound film.Compare with organic high molecular layer, inoranic membrane has very big advantage at aspects such as heat endurance, mechanical strength and chemical stabilities, nearly 20 for many years, and the exploitation of preparation of inorganic and infiltration evaporation separation process is domestic and international membrane science man and engineers and technicians' a research focus.In numerous inoranic membranes, zeolite molecular sieve film receives much concern because of the pore passage structure with rule, bigger specific area and strong absorption property.Wherein, the NaA molecular screen membrane has great application prospect aspect dewatering at organic solvent with its excellent hydrophilicity and pore structure with molecular dimension size.Compare with polyvinyl alcohol film, the infiltration evaporation running cost of NaA type molecular screen membrane only for the former 1/2.JP2003-210950 discloses the method for preparing the NaA molecular screen membrane on a kind of porous alumina carrier, and prepared NaA molecular screen membrane shows excellent separating property in the infiltration evaporation removal process of organic solvents such as ethanol, isopropyl alcohol.On this basis, Mitsui Ship-building Company has realized industrial applications (Morigami Y, Kondo M, et al.Sepn.Purifn.Tech., 2001,25,251～260 of NaA molecular screen membrane; Kondo M, Yamamura T, Yukitake T, et al.Sepn.Purifn.Tech., 2003,32,191～19).At present, there has been the NaA of cover more than 60 type molecular sieve film pervasion vaporization separator in Japan in operation.In NaA molecular screen membrane synthetic, the secondary hydrothermal synthesis method is maximum a kind of method of using at present.In this method, at first introduce layer of even NaA molecular sieve crystal seed on the surface of earthenware carrier, then support tube is placed molecular sieve precursor colloidal sol, the nucleation process and the crystal growing process of molecular sieve crystal are separated, under hydrothermal synthesizing condition, crystal growing process only takes place in the surface of carrier, thereby can form molecular screen membrane.Under common hydrothermal synthesizing condition, along with the carrying out of time and the growth of crystal, the density of the colloidal sol of body in mutually increases, because the effect of gravity, reactor axially and radially can form bigger concentration gradient, thereby cause the inhomogeneous of molecular screen membrane surface crystallization, be difficult to form fine and close continuous molecular screen membrane.Therefore, in the molecular screen membrane preparation process, how effectively avoiding occurring bigger concentration gradient is a challenge, particularly for the molecular screen membrane for preparing the commercial Application scale, because general film length of tube is 80-100 centimetre, the influence of axial concentration gradient will be bigger in the preparation process.CN1597072 adopts the method that the film pipe is horizontal to prepare the NaA molecular screen membrane, can reduce the concentration gradient of film tube-surface in solution, has prepared the vapor permeable membrance with higher separating property.CN1274396C has reported a kind of method of the synthetic A type molecular sieve film of original position hydro-thermal of finding time, and the use water pump is found time or the method for compressor compresses impels the nucleus that forms in the synthetic liquid to move to membrane surface rapidly, thereby accelerates synthetic A type molecular sieve film.Adopt this method, can significantly reduce generated time, improve utilization ratio of raw materials, the synthetic continuous molecular screen membrane of even compact.
Summary of the invention
The purpose of this invention is to provide a kind of new method for preparing the A type molecular sieve film, molecular screen membrane all is the methods that prepare in static enclosed system in open source literature different from the past and the patent report, the present invention adopts and prepare molecular screen membrane in current system, order about the outer membrane face flow circuit of molecular sieve precursor colloidal sol by slush pump at the carrier film pipe, thereby can fundamentally avoid the concentration gradient problem in the sieve synthesis procedure, help preparation evenly, continuously, fine and close, the molecular screen membrane of separating property excellence is particularly suitable for preparing the molecular screen membrane of commercial Application scale.
The invention provides the new method of preparation A type molecular sieve film in a kind of current system, it is characterized in that silicon source, aluminium source, alkali source and deionized water are prepared into according to certain ratio the molecular sieve precursor colloidal sol of homogeneous.Precoating is fixed in the synthesis reaction vessel assembly with the support tube of molecular sieve crystal seed, and the two ends of support tube are with the sealing of PTFE rod, and the reactor assembly places thermostatic drying chamber or twines the heating tape in the outside.Heating and constant temperature are input in the synthesis reaction vessel assembly by slush pump to the molecular sieve precursor colloidal sol of uniform temperature, and in the shell of reactor and support tube formation, circulate with certain speed.The temperature of precursor colloidal sol and synthesis reaction vessel is consistent, and behind the crystallization certain hour, the molecular screen membrane pipe is taken out, and fully washs, promptly obtains molecular screen membrane after the drying with deionized water.
Said silicon source can be sodium metasilicate, Ludox, silicon gel etc. among the preparation method provided by the present invention, and said aluminium source can be metallic aluminium, aluminium hydroxide, sodium aluminate etc., and alkali source is a NaOH etc.
The mole of said molecular sieve precursor colloidal sol consists of Na among the preparation method provided by the present invention
2O: SiO
2: Al
2O
3: H
2O=a: b: 1: c, a=0.5-5 wherein, b=1-5, c=50-500.
Said support tube can be a porous ceramic pipe among the preparation method provided by the present invention, also can be the porous metals pipe, and the average pore size of support tube is 0.1-10 μ m, and porosity is 30-60%; The external diameter of support tube is 10-13mm, and wall thickness is 1-3mm, and length is 1-100 centimetre.
The pre-coated method of said crystal seed can be in-situ low-temperature synthetic method, dip coating or mechanical friction method among the preparation method provided by the present invention.
The temperature of said precursor colloidal sol and reactor is 50-150 ℃ among the preparation method provided by the present invention, preferred 90-110 ℃.
The said crystallization time is 1-10 hour among the preparation method provided by the present invention, preferred 2-5 hour.
Said precursor flow of sol speed is 1-100ml/min among the preparation method provided by the present invention, preferred 10-50ml/min.
Description of drawings
Fig. 1 is the device schematic diagram of preparation molecular screen membrane in the current system provided by the present invention
Fig. 2 is the used infiltration evaporation separate evaluation device schematic diagram of the present invention
Fig. 3 is the separating resulting figure of the prepared NaA molecular screen membrane of invention to the THF/ aqueous systems
Fig. 4 is the separating resulting figure that the NaA molecular screen membrane separates THF/ water (90%/10%) system under the different temperatures
The specific embodiment
The preparation of embodiment 1:NaA type molecular screen membrane
With sodium metasilicate, sodium aluminate, NaOH and distilled water is the precursor colloidal sol of raw material configuration NaA molecular sieve, and the mol ratio of each component is in the colloidal sol: SiO
2: Al
2O
3: Na
2O: H
2O=2: 1: 2: 120, at room temperature fully mix.Be fixed in the synthesis reactor shown in Figure 1 after precoating sealed with the PTFE rod with tubular inorganic membrane (commercially available product, average pore size 1.5 μ m, porosity 38%, external diameter 13mm, internal diameter 8mm, the length 350mm) two ends of NaA molecular sieve kind crystallization.Molecular sieve precursor colloidal sol is heated to 100 ℃ in raw material storage tank after, squeeze in the synthesis reactor with the speed of 30ml/min with slush pump, the parcel heating tape, the outside of synthesis reactor, temperature constant is at 100 ℃.In entire reaction course, precursor colloidal sol flows in the outer loop of film pipe, and the axial and radial direction of film pipe can not produce concentration gradient.React after 3 hours, the molecular screen membrane pipe is taken out, fully wash to neutrality, promptly get the molecular screen membrane of falling NaA behind the natural drying at room temperature with distilled water.
The Pervaporation Separation of embodiment 2:NaA molecular screen membrane
Fig. 2 is the molecular sieve film pervasion vaporization separator schematic diagram among the present invention.The molecular screen membrane pipe places stainless assembly, and an end links to each other with a bit of teflon rod, and the other end links to each other with vacuum system, and two ends seal successively with silicone rubber tube and thermoplastic tube respectively, the outer wrap heating tape of assembly.The material liquid that is heated to uniform temperature in thermostat permeates steam liquid N by the supply that circulate of liquid pump in assembly
2Condensation is reclaimed, and two cold-traps switch use to guarantee continuous measurement.The penetrating fluid scales/electronic balance weighing that condensation is collected, the concentration of material liquid and penetrating fluid quantitatively detects with gas-chromatography respectively.Separating property is mainly by permeation flux Q (kg/m
2H) and separation α represent that wherein permeation flux Q represents the size by the infiltration capacity of film, computational methods are quality/(unit interval * membrane area) of the penetrant that the per-meate side condensation is collected in the unit interval.Separation is represented the height of molecular screen membrane separative efficiency, and computational methods are α
A/B=(Y
A/ Y
B)/(X
A/ X
B), wherein Y and X represent the mass concentration of A and two kinds of components of B in penetrant and the material liquid respectively.
The NaA molecular screen membrane that embodiment 1 prepares sees Table 1 for different solvents infiltration evaporation separating resulting, and as can be seen, the NaA molecular screen membrane that the present invention synthesizes has very excellent permeation vaporization separating property.
Embodiment 3:NaA molecular screen membrane is to THF/H
2The infiltration evaporation of O system separates
THF is a kind of very important organic solvent, is widely used in industries such as pharmacy, chemical industry, electronics.Because THF costs an arm and a leg, it separates recovery is very important for resources effective utilization and environmental protection.THF and H
2O forms azeotropic during for 95wt% at content and forms, and azeotropic point is 63.4 ℃.Separation method commonly used at present is azeotropic distillation and extractive distillation with salt etc., the energy consumption height, and the adding of entrainer and extractant is seriously polluted for environment and product.The mixed solution that contains THF 50wt% with 200ml is a raw material, separates THF/H with the A type molecular sieve film infiltration evaporation method of embodiment 1 preparation
2The O mixture, the infiltration evaporation separating resulting is seen Fig. 3.As can be seen, the A type molecular sieve film is for THF and H
2The O system has very excellent separating property, has broken through azeotropic restriction in the short time.Fig. 4 has provided temperature to THF/H
2O (90wt%/10wt%) influence of system Pervaporation Separation, permeation flux is along with the rising of temperature continues to increase, and separation remains unchanged substantially.
Embodiment 4: according to the synthetic method of embodiment 1, different is that crystallization time is 2.5 hours.The infiltration evaporation performance sees Table 2.
Embodiment 5: according to the synthetic method of embodiment 1, different is that crystallization time is 3.5 hours.The infiltration evaporation performance sees Table 2.
Embodiment 6: according to the synthetic method of embodiment 1, different is that crystallization time is 4 hours.The infiltration evaporation performance sees Table 2.
Table 1, A type molecular sieve film are to different solvents infiltration evaporation separating resulting
Table 2, different synthesis condition are to the infiltration evaporation separating resulting of ethanol/water (90%/10%) system
| Crystallization time (hour) | Crystallization temperature (℃) | Q (kg/m 2·h) | α H2O/C2H5OH | |
| Embodiment 4 | 2.5 | 100 | 1.54 | 500 |
| |
3 | 100 | 1.56 | 2150 |
| |
3.5 | 100 | 1.55 | 4555 |
| |
4 | 100 | 1.34 | 532 |
。
Claims (8)
1. the new method of preparation A type molecular sieve film in the current system is characterized in that silicon source, aluminium source, alkali source and deionized water are prepared into according to certain ratio the molecular sieve precursor colloidal sol of homogeneous; Precoating is fixed in the synthesis reaction vessel assembly with the support tube of molecular sieve crystal seed, and the two ends of support tube seal with teflon rod, and the reactor assembly places thermostatic drying chamber or twines the heating tape in the outside; Heating and constant temperature are input in the synthesis reaction vessel assembly by slush pump to the molecular sieve precursor colloidal sol of uniform temperature, and in the shell of reactor and support tube formation, circulate with certain speed; The temperature of precursor colloidal sol and synthesis reaction vessel is consistent, and behind the crystallization certain hour, the molecular screen membrane pipe is taken out, and fully washs, promptly obtains molecular screen membrane after the drying with deionized water.
2. according to the method for preparing molecular screen membrane in the described current system of claim 1, it is characterized in that the silicon source is sodium metasilicate, Ludox or silicon gel; The aluminium source is metallic aluminium, aluminium hydroxide or sodium aluminate; Alkali source is a NaOH.
3. according to the method for preparing molecular screen membrane in the described current system of claim 1, it is characterized in that the mole of molecular sieve precursor colloidal sol consists of Na
2O: SiO
2: Al
2O
3: H
2O=a: b: 1: c, a=0.5-5 wherein, b=1-5, c=50-500.
4. according to the method for preparing molecular screen membrane in the described current system of claim 1, it is characterized in that support tube is porous ceramic pipe or porous metals pipe, the average pore size of support tube is 0.1-10 μ m, and porosity is 30-50%; The external diameter of support tube is 10-13mm, and wall thickness is 1-3mm, and length is 1-100 centimetre.
5. according to the method for preparing molecular screen membrane in the described current system of claim 1, the pre-coated method that it is characterized in that crystal seed is in-situ low-temperature synthetic method, dip coating or mechanical friction method.
6. according to the method for preparing molecular screen membrane in the described current system of claim 1, the temperature that it is characterized in that precursor colloidal sol and reactor is 50-150 ℃, preferred 90-110 ℃.
7. according to the method for preparing molecular screen membrane in the described current system of claim 1, it is characterized in that the crystallization time is 1-10 hour, preferred 2-5 hour.
8. according to the method for preparing molecular screen membrane in the described current system of claim 1, it is characterized in that precursor flow of sol speed is 1-100ml/min, preferred 10-50ml/min.
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| CNA200710049348XA CN101402022A (en) | 2007-06-22 | 2007-06-22 | Novel methods for producing type A molecular sieve film in current system |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102247768A (en) * | 2011-05-05 | 2011-11-23 | 武汉科技大学 | Method for preparing NaA molecular sieve membrane by utilizing thermal impregnation seeding method |
| CN103846018A (en) * | 2012-12-06 | 2014-06-11 | 中国科学院成都有机化学有限公司 | Method for synthesizing NaA molecular sieve membrane by spraying crystal seeds |
| CN105056769A (en) * | 2015-07-21 | 2015-11-18 | 江苏九天高科技股份有限公司 | Method and device for preparation of NaA zeolite membrane |
| CN105195029A (en) * | 2015-10-21 | 2015-12-30 | 吉林大学 | Method for synthesizing NaA type molecular sieve crystals and synthesizing NaA type molecular sieve film |
| CN106842062A (en) * | 2017-03-29 | 2017-06-13 | 广州中国科学院工业技术研究院 | Secondary cell thermal runaway test device and its method of testing |
| CN107335343A (en) * | 2017-09-06 | 2017-11-10 | 李晨舒 | A kind of synthesizer and synthetic method of doughnut NaA molecular sieve membrane |
| CN107930411A (en) * | 2017-12-20 | 2018-04-20 | 江苏九天高科技股份有限公司 | The preparation method and device of a kind of molecular screen membrane |
| CN109012196A (en) * | 2018-07-04 | 2018-12-18 | 华东理工大学 | The doughnut inner wall NaA type molecular sieve infiltrating and vaporizing membrane and its synthetic method dynamically synthesized in a kind of continuous current system |
| CN109364767A (en) * | 2018-12-27 | 2019-02-22 | 延海港 | A kind of preparation method for industrial solvent dehydration membrane material |
| CN109433022A (en) * | 2018-12-27 | 2019-03-08 | 延海港 | A kind of preparation method of alcohol permselective membrane material |
| CN109433020A (en) * | 2018-12-27 | 2019-03-08 | 延海港 | It is a kind of for the industrial solvent dehydration preparation method of tubular type membrane material |
-
2007
- 2007-06-22 CN CNA200710049348XA patent/CN101402022A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102247768A (en) * | 2011-05-05 | 2011-11-23 | 武汉科技大学 | Method for preparing NaA molecular sieve membrane by utilizing thermal impregnation seeding method |
| CN103846018A (en) * | 2012-12-06 | 2014-06-11 | 中国科学院成都有机化学有限公司 | Method for synthesizing NaA molecular sieve membrane by spraying crystal seeds |
| CN105056769A (en) * | 2015-07-21 | 2015-11-18 | 江苏九天高科技股份有限公司 | Method and device for preparation of NaA zeolite membrane |
| CN105195029A (en) * | 2015-10-21 | 2015-12-30 | 吉林大学 | Method for synthesizing NaA type molecular sieve crystals and synthesizing NaA type molecular sieve film |
| CN106842062A (en) * | 2017-03-29 | 2017-06-13 | 广州中国科学院工业技术研究院 | Secondary cell thermal runaway test device and its method of testing |
| CN107335343A (en) * | 2017-09-06 | 2017-11-10 | 李晨舒 | A kind of synthesizer and synthetic method of doughnut NaA molecular sieve membrane |
| CN107930411A (en) * | 2017-12-20 | 2018-04-20 | 江苏九天高科技股份有限公司 | The preparation method and device of a kind of molecular screen membrane |
| CN109012196A (en) * | 2018-07-04 | 2018-12-18 | 华东理工大学 | The doughnut inner wall NaA type molecular sieve infiltrating and vaporizing membrane and its synthetic method dynamically synthesized in a kind of continuous current system |
| CN109012196B (en) * | 2018-07-04 | 2021-07-30 | 华东理工大学 | Hollow fiber inner wall NaA type molecular sieve pervaporation membrane dynamically synthesized in continuous flow system and synthesis method thereof |
| CN109364767A (en) * | 2018-12-27 | 2019-02-22 | 延海港 | A kind of preparation method for industrial solvent dehydration membrane material |
| CN109433022A (en) * | 2018-12-27 | 2019-03-08 | 延海港 | A kind of preparation method of alcohol permselective membrane material |
| CN109433020A (en) * | 2018-12-27 | 2019-03-08 | 延海港 | It is a kind of for the industrial solvent dehydration preparation method of tubular type membrane material |
| CN109364767B (en) * | 2018-12-27 | 2021-12-21 | 吴乐毅 | Preparation method of membrane material for industrial solvent dehydration |
| CN109433022B (en) * | 2018-12-27 | 2021-12-24 | 王玲娟 | Preparation method of alcohol permeable membrane material |
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