CN1141170C - Composite filtering film with ground filled with porous material and its production method - Google Patents
Composite filtering film with ground filled with porous material and its production method Download PDFInfo
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- CN1141170C CN1141170C CNB011185953A CN01118595A CN1141170C CN 1141170 C CN1141170 C CN 1141170C CN B011185953 A CNB011185953 A CN B011185953A CN 01118595 A CN01118595 A CN 01118595A CN 1141170 C CN1141170 C CN 1141170C
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Abstract
The present invention provides a composite filtering film with a base material filled with a porous material and a manufacturing method thereof. One or a plurality of raw materials for the film are firstly dissolved in a solvent at certain temperature, an additive is added to the solvent which is then stirred, filtered and manufactured into film casting liquid; then, the film casting liquid is cast or sprayed and coating in the relatively coarse base material of the filtering film, and forms a transitional thin film together with the base material after the solvent is volatilized; the transitional thin film is put in a precipitant solution, the additive is extracted out, and a porous film with certain compactness is formed, cleanly rinsed and dehydrated and then is heated and dried. The manufactured composite filtering film has the advantages of small pore diameter, high filtering efficiency, little resistance, large controllable range of the pore diameter and low cost. A filter manufactured by using the film can be widey used for environmental-protection engineering and biological fermentation engineering.
Description
Technical field
The present invention relates to a kind of manufacture method that is applicable to the filtering material of liquid and gaseous state, particularly make the method for composite filtering film with gel phase method for transformation filling porous material in ground.
Background technology
Environmental protection and biological fermentation engineering need a large amount of gas and efficient liquid filter in (comprising industries such as pharmacy, glutamate production).At present, the filter membrane material of installing in the filter and the manufacturing process of filter membrane are various, respectively have the characteristics of each, also respectively have the limitation of each.The metallic nickel film is wherein a kind of, and its used technology is to make the suitable nickel powder of granularity earlier, uses rolling or spray mo(u)lding then, and sintering curing is welded into tubulose after removing the diaphragm that a part contains loophole, tests again, and the filtering accuracy eligible is a finished product.The structure of metallic nickel film has two kinds: monofilm and duplicature, and the ground of duplicature creates earlier, and then adds the thin and thin mesopelagic layer of last layer, and duplicature is more far better than uniform monofilm performance, but the manufacturing process complexity.The metallic nickel film needing to be used for the gas high efficiency particulate air filter of steam sterilization more.Because yield rate is generally lower, the manufacturing process complexity, cost is higher.Metal titanium membrane also has good performance, and its manufacturing process is similar with the metallic nickel film, but cost is higher.That pure polytetrafluoroethylene (PTFE) and pure polyvinylidene fluoride high efficiency filter film have is corrosion-resistant, even structure and advantage such as be easy to fold, generally than metal film low cost of manufacture, but far above the cost of glass fibre membrane.Its hear resistance is but not as metal film, during the water steam disinfection, temperature drift some, just become very soft, distortion under vapor stream impacts, the sterilization back will reduce filter efficiency, even can not use fully because of very fast cooling is difficult to reinstatement.The also available powder process of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride filter membrane, moulding and sintering method manufacturing, but because of granularity is difficult to do very carefully, filtering accuracy can be very not high.Its filtering accuracy of poly tetrafluoroethylene with expanded manufactured is higher, but resistance is bigger than normal.For liquid filter, because the hydrophobicity of fluoroplastics needs higher pressure differential, pure fluoroplastics not to be suitable for hydrating solution and filters when filtering in the aqueous solution.
The filter paper made from glass fibre has the advantage that porosity is big, resistance is little, and manufacturing process is similar to general paper technology, and is comparatively simple, and cost is also low.Glass fibre itself is heat-resisting, during sterilization steam temperature degree height some also be unlikely to the distortion, this point is better than fluoroplastics film.But necessarily require the adhesive of glass fiber filter paper under this temperature, still to play adhesive effect, never degenerate, do not decompose, water insoluble.Because of glass fibre is difficult to do very carefully, its filtering accuracy is just not really high, generally it is used for the filtration of giving of fine filter.The glass fiber filter paper of buying on market is generally not water-fast, can not filtering solution, repeatedly water steam disinfection.
Summary of the invention
The object of the present invention is to provide a kind of in ground filling porous material make the method for composite filtering film, make composite filtering film with gel phase conversion method filling porous material in thick relatively film ground; It is little that this composite filtering film has the aperture, the filter efficiency height, and resistance is little, low cost and other advantages.
The object of the present invention is achieved like this: filling porous material is made the method for composite filtering film in ground, comprises following processing step:
(1) at a certain temperature one or more pleurodiaphragmatic in terspace material is dissolved in the solvent earlier, and adds additive, make casting solution through agitation and filtration;
(2) then casting solution is poured into a mould or sprayed in the thick relatively ground, form transitional film together with ground after the solvent evaporates of casting solution;
(3) transitional film is put into the precipitant solution of uniform temperature, additive is extracted, form the perforated membrane of certain compactness, after perforated membrane was finished, rinsing was clean, dehydration;
(4) carry out heat drying again, detect the qualified finished product that gets.
Said thick relatively filter membrane ground is metal film and the all-glass paper double-layered compound film that the nonwoven of 50～100 microns of 70～200 microns glass fiber filter paper of thickness, thickness, metallic nickel film that thickness is 15～40 microns or thickness are 40～180 microns.
Said pleurodiaphragmatic in terspace material is one or two or more kinds in polyvinylidene fluoride (PVDF), polyvinyl alcohol, formaldehyde, calcium chloride, ammonium fluoride, polyphosphazene polymer acid amides, epoxy resin and the Versamid.
Said solvent is one or two or more kinds in dimethyl formamide (DMF), N methyl pyrrolidone (NMP), dimethylacetylamide, ethanol, acetone and the pure water; Said additive is one or two or more kinds in lithium chloride, polyvinylpyrrolidone (PVP), calcium chloride and the sulfuric acid.
Said precipitating reagent is pure water, ethanol water or formalin etc.
With terylene non-woven fabric or polyester non-woven fabric is ground, with polyvinylidene fluoride (PVDF) is the pleurodiaphragmatic in terspace material, lithium chloride and polyvinylpyrrolidone (PVP) are additive, dimethyl formamide (DMF) and N methyl pyrrolidone (NMP) are solvent, preparation casting solution each inventory ratio is to be 1000ml altogether when solvent and the double sweller of doing of acetone, solvent and acetone volume ratio are 1: 0.15～0.3 o'clock, pleurodiaphragmatic in terspace material PVDF is 60～120 grams, additive is 20～40 grams, wherein lithium chloride and polyvinylpyrrolidone (PVP) weight ratio is 1: 0.5～1, and the preparation temperature is 27～33 ℃; Precipitating reagent is that ethanol water, pure water and ethanol volume ratio are 1: 0.3～0.7, and precipitant solution is constant between 20～30 ℃.
In addition, in casting solution, can also add: epoxy resin 20-60 gram, polyphosphazene polymer acid amides 20～40 grams, Versamid 10～20 grams.
With glass fiber filter paper or the fine nonwoven that sinks is ground, with the polyvinyl alcohol is that pleurodiaphragmatic in terspace material, calcium chloride and the concentrated sulfuric acid are that additive, pure water are solvent, each inventory ratio of preparation casting solution is 1000 milliliters of pure water, polyvinyl alcohol and calcium chloride 80～160 grams, both weight ratios are 1: 0.5～2,5～10 milliliters of the concentrated sulfuric acids, the preparation temperature is 90～95 ℃; Precipitating reagent is a formalin, contains 80～160 milliliters in 37% formaldehyde, and ground and the precipitating reagent of having coated casting solution carry out condensation reaction together, and temperature is controlled at 55～90 ℃, 18～28 hours time.
With the glass fiber filter paper is ground, with the polyphosphazene polymer acid amides is that pleurodiaphragmatic in terspace material, calcium chloride are that additive, ethanol are solvent, when preparation casting solution each inventory is 1000 milliliters of ethanol, polyphosphazene polymer acid amides and calcium chloride totally 100～200 grams, both weight ratios are 1: 0.5～2, and the preparation temperature is 50～72 ℃; Precipitating reagent is a pure water, and the precipitant solution temperature is a room temperature.
With metallic nickel film or glass fiber filter paper or its both bond is ground, with calcium chloride is that pleurodiaphragmatic in terspace material, polyvinyl pyrrolidone are that additive, ethanol are solvent, when preparation casting solution each inventory is 1000 milliliters of alcohol solvents, calcium chloride and polyvinyl pyrrolidone 100～200 grams, both weight ratios are 1: 0.5～2, and the preparation temperature is a room temperature; Precipitating reagent is that fluorinated ammonia is 30～60 grams in 1000 milliliters of the ammonium fluoride aqueous solution, pure water, and the precipitant solution temperature is controlled at below 10 ℃.
The method that filling porous material is made composite filtering film in ground provided by the invention has following advantage: the coarse filtration film that its porosity is big, resistance is little, the heat-and corrosion-resistant performance is good, intensity is high and use cost is low is a ground; Use the gel conversion method, casting solution is filled in the filter membrane ground of relative phase, realized the conversion of liquid phase,, create thinner composite filtering film to produce thinner porous mass to solid phase.Casting solution has suitable viscosity, and ground is had wellability.Composite efficient filters film strength and is mainly provided by ground, the main filtration of the porous mass of generation, and casting solution is very even in ground, and it is little to inject the degree of depth, and the thickness of porous mass that can control new generation is as far as possible little, and resistance can diminish thereupon; Heat treated purpose is to stablize the performance indications of perforated membrane, makes in depositing process the performance parameter drift little.The composite filtering film of making can satisfy the needs of environmental protection and biological fermentation engineering.
The specific embodiment
Embodiment 1: be the efficient PVDF membrane of ground manufacturing with the nonwoven.
With polyvinylpyrrolidone (PVDF) is membrane material, lithium chloride and polyvinylpyrrolidone (PVP) are additive, dimethyl formamide (DMF) and N methyl pyrrolidone (NMP) are solvent, wherein, dimethyl formamide (DMF) and N methyl pyrrolidone (NMP) volume ratio are 6: 1, each inventory of preparation casting solution is: solvent and acetone are 1000ml altogether, wherein solvent is that 800ml, acetone are 200ml, polyvinylpyrrolidone (PVDF) is 100 grams, and additive is 25 grams, wherein lithium chloride 15 grams, polyvinylpyrrolidone (PVP) 10 restrain.Under 30 ℃ of constant temperature above-mentioned pleurodiaphragmatic in terspace material and additive are dissolved in the solvent that adds acetone under 30 ℃ of constant temperature, acetone is made sweller, and stirs, natural deaeration and filter after promptly make casting solution.Ground polyester nonwoven, 50 gram/rice 2, smooth with milling train, outgoing gauge is controlled at 70 microns.Precipitating reagent is an ethanol water, pure water and proportion of ethanol 1: 0.5.If improve hydrophobicity, can in above-mentioned casting solution, add epoxy resin (E-51 etc.) 30 grams, polyphosphazene polymer acid amides 30 grams, Versamid 15 grams.Produce and experiment in as long as after the solvent for use amount was determined, remaining material increased and decreased in proportion according to solvent change.
By hand or mechanical way, casting solution is poured into or sprays in the clean smooth nonwoven (with the roller tension of mechanical device), scrape off unnecessary glue, and prevent show-through and produce loophole.Solvent evaporation in the air at room temperature.30 ℃ of ethanol waters of the constant temperature of putting into then extract additive, and polymer solidifies rapidly and precipitation, are formed with the PVDF membrane perforated membrane of certain porosity.Then, clean with the distilled water rinsing, in supercentrifuge, dewater, heating, drying is product after the test passes.
The prepared efficient PVDF membrane of this example maximum diameter of hole is 0.8 micron, and average pore size is 0.6 micron, and filtering accuracy is 0.3 micron, effectively the bacterium in the filtered air.The polyvinylidene fluoride composite membrane that hydrophobicity is improved can be used for water filtration.
Embodiment 2: with all-glass paper or nonwoven is that ground is made the polyvinyl formal composite membrane.
Casting solution is by pure water (solvent), polyvinyl alcohol (pleurodiaphragmatic in terspace material), and calcium chloride (additive), sulfuric acid (another kind of additive) is formed, and formula of casting is: 1000 milliliters of pure water, polyvinyl alcohol 60 grams and calcium chloride 80 grams, 10 milliliters of the concentrated sulfuric acids, preparing temperature is 90 ℃.Precipitating reagent is a formalin, contains 100 milliliters in 37% formaldehyde, has coated the ground of casting solution and precipitating reagent and has contracted together and react, and temperature is controlled at 90 ℃, 18 hours time.Produce and experiment in as long as after the solvent for use amount was determined, remaining material increased and decreased in proportion according to solvent change.
Used ground is that thickness 70-200 micron glass fiber filter paper (glass fiber filter paper and JU filter paper with medium air filtration performance as having the primarily efficient filter performance), thickness are the nonwoven (as having the terylene non-woven fabric of the filter material of primarily efficient filter performance, polyester non-woven fabric etc.) of 50-100 micron.
Make high-efficiency polyethylene alcohol formal film when making ground, imitate polyvinyl alcohol formaldehyde film in making during with terylene non-woven fabric and polyester non-woven fabric ground with glass fiber filter paper.
Casting solution is poured into or sprays in the clean nonwoven (with the roller tension of mechanical device), scrape off unnecessary glue, and prevent show-through and the generation loophole.With electric heater heating or use the infrared lamp photograph, make the partial solvent evaporation.Put into precipitating reagent then, carry out condensation reaction, and additive is extracted, formed the perforated membrane of certain porosity.Then, clean with the distilled water rinsing, in supercentrifuge, dewater, heat drying is product after the test passes.
This routine prepared high-efficiency polyethylene alcohol formal composite membrane maximum diameter of hole is 0.7 micron, and average pore size is 0.5 micron, and filtering accuracy is 0.3 micron, effectively the bacterium in the filtered air.Imitating polyvinyl formal film average pore size in prepared is the 1-1.5 micron.
Embodiment 3: be that ground is made nylon membrane with the glass fiber filter paper
Ground is a thickness 70-200 micron glass fiber filter paper, and each material formula is in the casting solution: ethanol is solvent, 1000 milliliters, dissolve a kind of polyphosphazene polymer acid amides 60 grams and calcium chloride 90 grams, and the preparation temperature is 70 ℃, is frozen into solid under the room temperature.Precipitating reagent is a pure water.Produce and experiment in as long as after the solvent for use amount was determined, remaining material increased and decreased in proportion according to solvent change.
Under 70 ℃, casting solution is poured into or sprays on the clean ground, scrape off unnecessary glue rapidly, and prevent show-through and the generation loophole.With the film cool to room temperature, put into pure water behind the solvent evaporate to dryness, at room temperature calcium chloride is extracted, make composite porous film.Thereafter use the distilled water rinsing clean, centrifugal dehydration, heat drying (not above 90 ℃).
With finishing mill processing, control this membrane aperture, drafts difference, membrane aperture are also different, and resistance is also different thereupon.
This routine prepared nylon membrane membrane aperture can reach 0.1 micron.
Embodiment 4: with metal film or glass fiber filter paper or its both bond is that ground is made ultra-fine micropore calcirm-fluoride composite filtering film (micropore size is the perforated membrane of nanometer scale)
Formula of casting is 1000 milliliters of alcohol solvents, dissolving calcium chloride (pleurodiaphragmatic in terspace material) 100 grams and polyvinylpyrrolidone (additive) 100 grams.1000 milliliters of precipitating reagent pure water and ammonium fluoride 50 grams.Produce and experiment in as long as after solvent for use was determined, remaining material increased and decreased in proportion according to solvent change.
The preparation temperature is a temperature, and casting solution stirs the back and filters, and removes bubble end and solid impurity.
Ground is ultra-fine microporous metal membrane or glass fiber filter paper or its metal film and all-glass paper double-layered compound film, the thickness of metallic nickel film is 15～40 microns, the thickness of glass fiber filter paper is 70～200 microns, and the thickness of metal film and all-glass paper double-layered compound film is 40～180 microns.
Casting solution is poured into or sprays on the clean ground, and heating makes the solvent evaporation, the cooling of dry back.In the precipitating reagent under-10 ℃, carry out chemical reaction, put into water purification afterwards, continue extraction and rinsing.Centrifugal dehydration, heat drying is made ultra-fine micropore calcirm-fluoride film.
The prepared ultra-fine micropore calcirm-fluoride composite membrane of this example aperture can reach 0.01 micron, even littler, makes ground with ultra-fine Microporous Nickel film, and the composite membrane micropore size can reach nanometer scale.
More than the prepared efficient composite filtering film of several examples, the aperture of its film is little, the filter efficiency height, thickness is little, resistance is also little, aperture controlled range big (from micron order up to nanoscale).Technological operation is simple, the yield rate height, and cost is low, and the life-span is long, has better economic.Use the high efficiency particulate air filter of this filter membrane manufacturing can be widely used in environmental protection and biological fermentation process (comprising industries such as pharmacy, monosodium glutamate manufacturing) and toilet.
Claims (7)
1. filling porous material is made the method for composite filtering film in ground, ground is the relative thick filter membrane ground with the all-glass paper double-layered compound film of metal film that the nonwoven of 50～100 microns of 70～200 microns glass fiber filter paper of thickness, thickness, metallic nickel film that thickness is 15～40 microns or thickness are 40～180 microns, it is characterized in that may further comprise the steps:
(1) earlier one or two or more kinds pleurodiaphragmatic in terspace material such as said pleurodiaphragmatic in terspace material polyvinylidene fluoride (PVDF), polyvinyl alcohol, formaldehyde, calcium chloride, ammonium fluoride, polyphosphazene polymer acid amides, epoxy resin and Versamid is dissolved in the solvent, said solvent is one or two or more kinds in dimethyl formamide (DMF), N methyl pyrrolidone (NMP), dimethylacetylamide, ethanol, acetone and the pure water; And the adding additive, said additive be lithium chloride, polyvinylpyrrolidone (PVP), calcium chloride and sulfuric acid one or two or more kinds, make casting solution through agitation and filtration;
(2) then casting solution is poured into a mould or sprayed in the thick relatively filter membrane ground, form transitional film together with ground after the solvent evaporates of casting solution;
(3) transitional film is put into precipitant solution, additive is extracted, form the perforated membrane of certain compactness, after perforated membrane was finished, rinsing was clean, dehydration;
(4) carry out heat drying again, get finished product.
2. the method for manufacturing composite filtering film as claimed in claim 1, its feature is pure water, ethanol water or formalin etc. in said precipitating reagent.
3. the method for manufacturing composite filtering film as claimed in claim 1 or 2 is characterized in that with terylene non-woven fabric or polyester non-woven fabric be ground; With polyvinylidene fluoride (PVDF) is that pleurodiaphragmatic in terspace material, lithium chloride and polyvinylpyrrolidone (PVP) are that additive, dimethyl formamide (DMF) and N methyl pyrrolidone (NMP) are solvent, preparation casting solution each inventory ratio is that to cook sweller be that 1000ml, solvent and acetone volume ratio are when being 1: 0.15～0.3 altogether when solvent and acetone are double, pleurodiaphragmatic in terspace material polyvinylidene fluoride (PVDF) is 60～120 grams, additive is 20～40 grams, wherein lithium chloride and polyvinylpyrrolidone (PVP) weight ratio are 1: 0.5～1, and the preparation temperature is 27～33 ℃; Precipitating reagent is that ethanol water, pure water and ethanol volume ratio are 1: 0.3～0.7, and precipitant solution is constant between 20～30 ℃.
4. the method for manufacturing composite filtering film as claimed in claim 1 or 2 is characterized in that with terylene non-woven fabric or polyester nonwoven be ground; With polyvinylidene fluoride (PVDF) is the pleurodiaphragmatic in terspace material, lithium chloride and polyvinylpyrrolidone (PVP) are additive, dimethyl formamide (DMF) and N methyl pyrrolidone (NMP) are solvent, preparation casting solution each inventory ratio is to be 1000ml altogether when solvent and the double sweller of doing of acetone, solvent and acetone volume ratio are 1: 0.15～0.3 o'clock, pleurodiaphragmatic in terspace material polyvinylidene fluoride (PVDF) is 60～120 grams, additive is 20～40 grams, wherein lithium chloride and polyvinylpyrrolidone (PVP) weight ratio is 1: 0.5～1, in casting solution, add again: epoxy resin 20～40 grams, polyphosphazene polymer acid amides 20～40 grams, Versamid 10～20 grams, the preparation temperature is 27-33 ℃; Precipitating reagent is that ethanol water, pure water and ethanol volume ratio are 1: 0.3～0.7, and precipitant solution is constant between 20-30 ℃.
5. the method for manufacturing composite filtering film as claimed in claim 1 or 2 is characterized in that with glass fiber filter paper or the fine nonwoven that sinks be ground; With the polyvinyl alcohol is that pleurodiaphragmatic in terspace material, calcium chloride and the concentrated sulfuric acid are that additive, pure water are solvent, each inventory ratio of preparation casting solution is 1000 milliliters of pure water, polyvinyl alcohol and calcium chloride 80～160 grams, both weight ratios are 1: 0.5～2,5～10 milliliters of the concentrated sulfuric acids, and the preparation temperature is 90～95 ℃; Precipitating reagent is a formalin, contains 80～160 milliliters in 37% formaldehyde, and ground and the precipitating reagent of having coated casting solution carry out condensation reaction together, and temperature is controlled at 55～90 ℃, 18～28 hours time.
6. the method for manufacturing composite filtering film as claimed in claim 1 or 2 is characterized in that with the glass fiber filter paper being ground; With the polyphosphazene polymer acid amides is that pleurodiaphragmatic in terspace material, calcium chloride are that additive, ethanol are solvent, when preparation casting solution each inventory is 1000 milliliters of ethanol, polyphosphazene polymer acid amides and calcium chloride totally 100～200 grams, both weight ratios are 1: 0.5～2, and the preparation temperature is 50～72 ℃; Precipitating reagent is a pure water, and the precipitant solution temperature is a room temperature.
7. the method for manufacturing composite filtering film as claimed in claim 1 or 2 is characterized in that with metallic nickel film or glass fiber filter paper or its both bond be ground; With calcium chloride is that pleurodiaphragmatic in terspace material, polyvinyl pyrrolidone are that additive, ethanol are solvent, when preparation casting solution each inventory is 1000 milliliters of alcohol solvents, calcium chloride and polyvinyl pyrrolidone 100～200 grams, both weight ratios are 1: 0.5～2, and the preparation temperature is a room temperature; Precipitating reagent is that fluorinated ammonia is 30～60 grams in 1000 milliliters of the ammonium fluoride aqueous solution, pure water, and the precipitant solution temperature is controlled at below-10 ℃.
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| CNB011185953A CN1141170C (en) | 2001-06-06 | 2001-06-06 | Composite filtering film with ground filled with porous material and its production method |
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| CNB011185953A CN1141170C (en) | 2001-06-06 | 2001-06-06 | Composite filtering film with ground filled with porous material and its production method |
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| CN1141170C true CN1141170C (en) | 2004-03-10 |
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| CN1958780B (en) * | 2006-05-23 | 2010-10-06 | 重庆大学 | Solid-state fermentation bag, and application |
| CN101837247B (en) * | 2010-06-03 | 2012-11-21 | 武汉智迅创源科技发展股份有限公司 | Liquid medicine filtering membrane and preparation method thereof |
| CN110241629B (en) * | 2019-06-19 | 2020-12-25 | 中电保力（北京）科技有限公司 | Gas-phase antirust diaphragm and preparation method thereof |
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