CN104722211A - Automatic roll-coating method and automatic roll-coating device of ethanol-permselective composite membrane - Google Patents

Abstract

The invention discloses an automatic roll-coating method and device of an ethanol-permselective composite membrane, belonging to the technical field of membrane coating of separation membranes. A coating device comprises a roller, a gear, a support plate, a base, a motor, a feed liquid tank, a lifting table and the like. The coating method provided by the invention comprises the following steps: pouring membrane preparing liquid into a storage tank, conveying the feed liquid to the feed liquid tank through an automatic feeding device, adjusting the height of the feed liquid tank by using the lifting table and the scale marks at one end of the roller; rotating the roller through the driving of the motor so as to uniformly coat a base membrane with the feed liquid. Through the adoption of the method and the device disclosed by the invention, the thickness of a separation layer can be effectively controlled and reduced, the permeation flux is greatly improved, and the automatic coating of the ethanol-permselective composite membrane is realized.

Description

A kind of automatic roll coating method and device of alcohol-preferred composite film

technical field

The invention belongs to the technical field of separation membrane coating, and relates to an automatic coating device and method for a separation membrane, in particular to an automatic roll coating device and method for preparing an alcohol-preferential composite membrane.

Background technique

As oil prices rise, fuel ethanol and butanol, as a new type of biofuel, are highly valued by countries all over the world for their advantages of high efficiency and cleanliness. The coupling of pervaporation and biological fermentation technology is an important way to improve the fermentation rate and yield. Pervaporation uses selective membrane separation technology to achieve alcohol/water separation without evaporating the mixture to the boiling point, low energy consumption, high separation purity, no secondary pollution, and continuous operation of the entire system.

Generally speaking, the preparation methods of alcohol permeable films mainly include doctor blade coating method, dipping and pulling method and spin coating method. When preparing alcohol-preferential composite membranes by traditional methods, the thickness of the separation layer formed on the surface of the support is relatively thick, resulting in low permeation flux; or it is easy to form defects on the surface, resulting in unstable performance, which limits its industrial application. Therefore, it is urgent to develop a reasonable and advanced membrane-making process, reduce the thickness of the separation layer on the premise of ensuring the integrity of the separation layer, and prepare a separation layer with an excellent structure, which can greatly improve the flux and separation performance of the membrane.

Contents of the invention

The object of the present invention is to provide a kind of automatic roller coating method and device for preparing the composite membrane of alcohol penetration preferentially, the device and steps of the present invention are simple, can reduce the polymer thickness of membrane surface by the roller rotation technology, guarantee the separation layer at the same time Integrity, thereby improving the permeate flux of the membrane while ensuring the separation factor.

A kind of automatic coating device that preferentially permeates alcohol composite film provided by the present invention comprises cylinder (2), gear (11), support plate a (12) and support plate b (13), base (15), motor ( 9), feed liquid tank (6), lifting platform (16), peristaltic pump (19), feed pipe (20).

Support plate a (12) and support plate b (13) are respectively vertically fixed on the two ends of the upper surface of the base (15), forming a cavity in the middle, and the cylinder (2) is installed in this cavity, and the surface of the cylinder (2) is set There is a card slot (3), one end of the roller (2) is fixed on the support plate a (12) through the shaft (10) through the gear (11), the other end of the roller (2) is fixedly connected with the motor, and the motor drives the roller (2) Rotate, the motor is fixed on the support plate (b); the central axis of the drum (2) is kept horizontal; the feed liquid tank (6) is directly below the drum (2), and the feed liquid tank (6) is a rectangular plate tank, and the feed liquid A feed port (7) is provided on the side of the bottom of the tank (6), and a valve is provided on the feed port (7), and the feed port (7) is connected to the feed pipe (20) in a sealed manner, preferably the feed pipe is a hose , the feed pipe (20) is connected to the storage tank via a peristaltic pump (19); the lifting table (16) is directly below the feed tank (6), which is used to support and adjust the height of the feed tank (6), lift The platform (16) is placed on the base (15); the end surface of the support plate (a) side drum is engraved with a scale (17), which is used to indicate the depth of the surface of the drum immersed in the liquid, preferably at four angles of 90 degrees. The direction is engraved with a scale, and a visual window is opened on the support plate a to observe the depth of the surface of the drum immersed in the liquid.

The base film is fixed on the card groove on the surface of the roller through the clamping plate, and one end of the roller is fixed on the support plate (a) of the base through a gear connection with a shaft. The support plate (a) has a visual window; the other end of the roller is driven by a motor to make it Rotate, the motor is fixed on the support plate (b); the lower part of the roller is placed in the material liquid of the material liquid tank, and the height of the material liquid tank is adjusted by the lifting platform placed on the base; the material liquid tank has an inlet and outlet, and the inlet and outlet are controlled by The valve controls the switch and connects the automatic feeding device.

The method for preparing a preferential alcohol-penetrating composite film by using the above-mentioned automatic roller coating device is characterized in that, comprising the following steps:

(1) Polymer, crosslinking agent and catalyst are respectively dissolved in solvent to prepare film-making liquid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through a peristaltic pump and a feed pipe;

(3) Wrap the base film around the outer surface of the drum and fix both ends of the film in the slots of the drum with clamps, and adjust the depth of the lowest outer surface of the drum immersed in the feed liquid tank through the lifting table and the scale at one end of the drum;

(4) Turn on the power to make the motor drive the drum to rotate;

(5) Lower the lifting platform to make the drum run idly after leaving the membrane liquid surface, so that the liquid on the membrane is compounded more uniformly;

(6) Turn off the power supply, remove the film and dry it in the air for 6-12 hours, then place the film in an oven for vulcanization at a temperature of 50-150°C for 3-12 hours.

Generally, the lowest outer surface of the drum is immersed in the feed liquid tank to a depth of 0-3 cm, preferably 1-2 cm.

The rotational speed of the motor 9 is 1-30rmp, preferably 10rmp.

The polymer can be polydimethylsiloxane, polytrimethyl-1-propyne or polyvinyltrimethylsilane, preferably polydimethylsiloxane, with a mass concentration of 0.1%-25% The crosslinking agent can be ethyl orthosilicate, propyl orthosilicate, butyl silicate, diethoxysilane or dimethylsilane, preferably ethyl orthosilicate, with a mass concentration of 1%-3%; The catalyst can be dibutyltin dilaurate, monobutyltin oxide, dibutyltin oxide, tripropyltin oxide or dipropyltin oxide, preferably dibutyltin dilaurate, with a mass concentration of 0.01%-0.05%; the solvent is n-heptane or cyclohexane.

The base membrane is a microfiltration membrane, an ultrafiltration membrane, or a nanofiltration membrane. The base film material is an organic polymer film.

The organic polymer film can be polysulfone, polyacrylonitrile, polycarbonate, polyethylene, polyvinyl alcohol, polyhydroxymethylene, cross-linked polymethacrylate, polytetrafluoroethylene, polyvinylidene fluoride, poly Hexafluoropropylene or chitosan.

The coated composite membrane acts as a pervaporation preferential alcohol permeable membrane.

Compared with the prior art, the present invention has the following beneficial effects:

1. On the premise of effectively ensuring the integrity of the separation layer, the thickness of the separation layer can be controlled and reduced, which can be controlled by adjusting the depth of the lowest outer surface of the drum immersed in the material liquid tank and the number of layers of roll coating.

2. It can realize the automatic coating of the composite film with priority of alcohol penetration.

Description of drawings

Fig. 1 structural schematic diagram of automatic roller coating device;

Figure 2 is a schematic diagram of the side of the roller of the automatic roller coating device;

Fig. 3 is a schematic diagram of the structure of the automatic feeding device;

In the figure, 1-base film, 2-roller, 3-card slot, 4-card plate, 5-feed liquid, 6-feed liquid tank, 7-feed inlet and outlet, 8-valve, 9-motor, 10-axis , 11-gear, 12-branch (a), 13-branch (b), 14-visualization window, 15-base, 16-lift table, 17-scale, 18-storage tank, 19-peristaltic pump, 20 - Feed tube.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the present invention is not limited to the following examples.

As shown in Figures 1 to 3, the present invention provides an automatic roll-coating device for preparing an alcohol-preferential composite film. The base film 1 is fixed on the groove 3 on the surface of the drum 2 through a clamp 4, and one end of the drum 2 is used to The shaft 10 is connected and fixed on the support plate (a) 12 of the base 15 through the gear 11. The support plate a12 has a visual window 14; the other end of the drum is driven by a motor 9 to rotate, and the motor 9 is fixed on the support plate b13. The speed is 1-30rmp; the lower part of the drum 2 is placed in the feed liquid 5 of the feed liquid tank 6, and the feed liquid tank 6 is placed on the base 15 through the height adjustment of the lifting platform 16; the feed liquid tank has an inlet and outlet 7, and an inlet and outlet 7 The switch is controlled by valve 8 and connected to the automatic feeding device;

Described automatic feeding device comprises: storage tank 18, peristaltic pump 19 and flexible pipe 20;

One end of the drum 2 is equipped with four scales 17 arranged in a 90° direction, which are used to adjust the impregnation depth of the feed liquid during the rotation process to 0-3 cm, preferably 1-2 cm;

The rotational speed of the motor 9 is 1-30rmp, preferably 10rmp.

Example 1:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through the peristaltic pump and hose in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the coating machine with a clamp, adjust the height of the feed liquid tank through the lifting platform and the scale at one end of the roller, so that the lowest outer surface of the roller is immersed in the feed liquid to a depth of 1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 30 times, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 6 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1493g/m ² ·h, the ethanol content in the permeate is 56.28wt%, and the separation factor is 11.6.

Example 2:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through the peristaltic pump and hose in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting platform and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 0.1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 30 times, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above is observed with a scanning electron microscope and the thickness of the separation layer of the membrane section is 5 μm, and the pervaporation performance test is carried out in a pervaporation device. The test conditions are: the stock solution is composed of 10wt% ethanol/water system, the experimental temperature is 60 ° C, and the downstream pressure of the membrane is 200 Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1578g/m ² ·h, the ethanol content in the permeate is 44.3wt%, and the separation factor is 7.17.

Example 3:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through the peristaltic pump and hose in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting table and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 1 circle, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 0.2 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the pressure downstream of the membrane was 200 Pa.

The measured performance of the pervaporation membrane is as follows: the permeation flux is 2936g/m ² ·h, the ethanol content in the permeate is 41.58wt%, and the separation factor is 6.4.

Example 4:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through the peristaltic pump and hose in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting table and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 1cm;

(4) Turn on the power supply, start the film coating machine, make the motor drive the drum to rotate 10 times, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 2 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1571g/m ² ·h, the ethanol content in the permeate is 52.78wt%, and the separation factor is 10.1.

Example 5:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed storage tank, and transport the feed liquid to the feed liquid tank through the peristaltic pump and hose in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting table and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 20 times, and the motor speed is 10rmp;

(5) Lower the lifting platform to make the drum idling 5 times after leaving the membrane liquid surface, so that the liquid on the membrane is compounded more evenly,

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 5 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1500g/m ² ·h, the ethanol content in the permeate is 54.5wt%, and the separation factor is 10.8.

Embodiment 6:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed tank, and transport the feed liquid to the feed tank through the peristaltic pump and flexible pipe in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting table and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 40 times, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 7 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1429g/m ² ·h, the ethanol content in the permeate is 48.9wt%, and the separation factor is 8.6.

Embodiment 7:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Pour the above-mentioned feed liquid into the feed tank, and transport the feed liquid to the feed tank through the peristaltic pump and flexible pipe in the automatic feeding device;

(3) Fix the two ends of the base film in the groove of the roller of the film coating machine with a clamp, adjust the height of the feed liquid tank through the lifting table and the scale at one end of the roller, so that the depth of the roller immersed in the feed liquid is 1cm;

(4) Turn on the power, start the film coating machine, make the motor drive the drum to rotate 50 times, and the motor speed is 10rmp;

(5) Lower the lifting table, make the roller idling 5 times after detaching from the liquid surface of the membrane, so that the liquid on the membrane is compounded more evenly;

(6) Turn off the power supply, remove the film and place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 8 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 1357g/m ² ·h, the ethanol content in the permeate is 44.77wt%, and the separation factor is 7.3.

Comparative example 1:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel Dibutyltin acid;

(2) Immerse the base film in the composite solution for 1 min to form a separation layer, place it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form an alcohol-preferential film.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 3 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 10wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is: the permeation flux is 763g/m ² ·h, the ethanol content in the permeate is 44.9wt%, and the separation factor is 7.3.

Comparative example 2:

The base membrane is polysulfone (PS) material, a flat ultrafiltration membrane with a molecular weight cut-off of 20,000 and a membrane area of 600cm ² . The composite material used is polydimethylsiloxane (PDMS, viscosity 2500Pa·S), solvent for n-heptane.

Assembly conditions and methods:

(1) Polydimethylsiloxane (PDMS) is made into a 10wt% solution with n-heptane, and 1wt% crosslinking agent orthosilicate (TEOS) is added in the solution, and 0.02wt% catalyst dilaurel dibutyltin acid;

(2) Fix the base film on the smooth surface of the glass plate to ensure that the base film is flat and free of protrusions. Pour the above feed solution on the surface of the base film, and use a scraper to scrape from bottom to top to form a film. After forming a separation layer, put it in a constant temperature and low humidity environment to dry for 6-8 hours, then place the film in an oven at 80°C for 8 hours to vulcanize, and finally form a film with a preferential alcohol permeability.

The composite membrane assembled above was observed by a scanning electron microscope with a separation layer thickness of 2 μm, and the pervaporation performance test was carried out in a pervaporation device. The test conditions were: the stock solution was composed of 5wt% ethanol/water system, the experimental temperature was 60°C, and the downstream pressure of the membrane was 200Pa .

The measured performance of the pervaporation membrane is as follows: the permeation flux is 856g/m ² ·h, the ethanol content in the permeate is 30.5wt%, and the separation factor is 8.3.

Claims (10)

1. the automatic roll-on device of a prior-alcohol-permeacomposite composite membrane, it is characterized in that, comprise cylinder (2), gear (11), support plate a (12) and support plate b (13), base (15), motor (9), material fluid bath (6), lifting platform (16), peristaltic pump (19), feed pipe (20);

Support plate a (12) and support plate b (13) is vertically fixed on the two ends of base (15) upper surface respectively, middle composition cavity, cylinder (2) is arranged in this cavity, the surface of cylinder (2) is provided with draw-in groove (3), cylinder (2) one end axle (10) is fastened on support plate a (12) by gear (11), cylinder (2) other end is fixedly connected with motor, driven by motor cylinder (2) rotates, and motor is fixed on support plate (b); The central shaft of cylinder (2) keeps level; Material fluid bath (6) immediately below cylinder (2), material fluid bath (6) is rectangle board slot, material fluid bath (6) bottom sides is provided with charging aperture (7), charging aperture (7) is provided with valve, charging aperture (7) is tightly connected with feed pipe (20) is supporting, and feed pipe (20) is connected with storagetank via peristaltic pump (19); Be lifting platform (16) immediately below material fluid bath (6), for supporting and regulating the height of material fluid bath (6), lifting platform (16) is placed on base (15); The end face that support plate (a) sidewinders cylinder is carved with scale (17), and the degree of depth of feed liquid is immersed on the surface being used to indicate cylinder, and support plate a has visualization window, and the degree of depth of feed liquid is immersed on the surface for observing cylinder.

2. according to the automatic roll-on device of a kind of prior-alcohol-permeacomposite composite membrane of claim 1, it is characterized in that, feed pipe is flexible pipe.

3. according to the automatic roll-on device of a kind of prior-alcohol-permeacomposite composite membrane of claim 1, it is characterized in that, the four direction being 90 degree at angle is carved with scale.

4. adopt the arbitrary device described in claim 1-3 to prepare the method for prior-alcohol-permeacomposite composite membrane, it is characterized in that, comprise the following steps:

(1) polymer, crosslinking agent and catalyst are dissolved in a solvent respectively, be made into preparation liquid;

(2) by above-mentioned feed liquid impouring stock chest, by peristaltic pump and feed pipe, feed liquid is transported to material fluid bath;

(3) film two ends are fixed in the draw-in groove of cylinder around outer surface of cylinder with clamp by basement membrane, are immersed the degree of depth of material fluid bath by lifting platform and the minimum outer surface of cylinder one end scale adjustment cylinder;

(4) opening power, makes driven by motor drum rotating;

(5) reduce lifting platform, dally after making cylinder depart from film liquid liquid level, thus liquid compound on film is more even;

(6) turn off power supply, film is taken off after drying in the air 6-12 processed hour, film is placed in baking oven sulfuration, temperature 50-150 DEG C, time 3-12 hour.

5. according to the method for claim 4, it is characterized in that, it is 0 ~ 3cm that the minimum outer surface of general cylinder immerses material fluid bath degree of depth degree, and described motor (9) rotating speed is 1 ~ 30rmp.

6. according to the method for claim 5, it is characterized in that, it is 1 ~ 2cm that the minimum outer surface of general cylinder immerses the material fluid bath degree of depth.

7. according to the method for claim 4, it is characterized in that, described polymer can be dimethyl silicone polymer, poly-trimethyl-1-propine or polyvinyl trimethyl silane, and mass concentration is 0.1%-25%; Crosslinking agent is ethyl orthosilicate, positive silicic acid propyl ester, butyl silicate, diethoxy silane or dimethylsilane, and mass concentration is 1%-3%; Catalyst is dibutyl tin laurate, Mono-n-butyltin, Dibutyltin oxide, tripropyl tin oxide or dipropyl tin oxide, mass concentration 0.01%-0.05%, and solvent is normal heptane or cyclohexane.

8. adopt method according to claim 1, described basement membrane is microfiltration membranes, milipore filter or NF membrane, and basal lamina material is organic polymer films.

9. according to the method for claim 8, it is characterized in that, described organic polymer films is polysulfones, polyacrylonitrile, Merlon, polyethylene, polyvinyl alcohol, Polyhydroxymethylene, CARBOPOL, polytetrafluoroethylene (PTFE), Kynoar, polyhexafluoropropylene or shitosan.

10. the composite membrane applied according to the method for claim 4 is as evaporation alcohol permselective membrane.