KR970007055B1 - Separater film of ceramics and preparation thereof - Google Patents

Abstract

A ceramic separation membrane the method for preparing thereof comprising the step depositing the far infrared rays radiation ceramic containing 0.1~5wt% of MnO2, CuO, FeO, the metal catalyst of 2-ion & 3-ion Fe as metal with polyurethan resin on polyethylene nonwoven and then the step coating it with chitous acid and then fixing it is disclosed. Thereby, the membrane is stable to water or organic solvent, has high mechanical tensile strength, and is able to selectively separate polymer compound, organic compound and heavy metal oxide from sewage and contaminated air.

Description

Ceramic Separator and its Manufacturing Method

1 is an enlarged photograph of the surface of the ceramic separator of the present invention, (a) is a 200 times magnification before performing filtration, (b) is a 300 times magnification after performing filtration.

2 is an enlarged photograph of the cross section of the ceramic separator of the present invention, (a) is a 2000 times magnification before chitosan coating, and (b) is a 3000 times magnification after chitosan coating.

The present invention relates to a ceramic separator and a method for manufacturing the same, and in particular, by depositing a far-infrared radiation ceramic containing a metal catalyst on a polymer synthetic resin and coating and fixing it with a chitosan solution, which is a deacetylate of chitin, The present invention relates to a ceramic separator and a method for producing the same, which are stable to organic solvents and have high mechanical elongation strength and good water permeability, and are capable of selectively separating polymer compounds, organic compounds, heavy metal oxides, and the like from sewage and polluted air.

As industrial development and population increase, pollution of air and river water becomes more and more serious, and efforts are being made to purify polluted air and river water. There is a filtration method that uses a filter as a method of purifying polluted air by removing harmful gases generated from vehicles and heating facilities that cause air pollution, but this is mainly due to dust and other constants in the air introduced into the air purifier. The use of filters made of synthetic fiber nonwovens to filter out solid particles larger than size is only a secondary means of air purification. In addition, there is a physical, chemical and biological treatment step of the river water purification process, there is a filtration step of removing suspended solids by passing water through a medium layer made of sand, activated carbon, diatomaceous earth, finely woven fibers, etc. This is only a minor step in sewage purification.

On the other hand, in the industrial field, microfiltration membranes with pore sizes ranging from 0.1 to several ten μm are used for the purpose of purifying air for ultra-clean systems in precision instrument fields such as filtration of incoming air for air conditioning systems and semiconductor applications. . As the material constituting the microfiltration membrane, a polymer synthetic resin such as cellulose acetate, polyacrylonitrile or polyamide is used, and hollow fibers such as polyether sulfone-based may be used. Such a microfiltration membrane has a problem in that it is difficult to uniformly manufacture the distribution of pores and requires expensive equipment. In addition, the microfiltration membrane thus prepared is not only susceptible to chemicals and alkalis and is easily susceptible to alkali and acid, but also the pores are easily blocked due to colloidal particulates and other filtered impurities. It should be replaced with one.

On the other hand, far infrared rays refer to a long wavelength portion in the infrared region of wavelength 0.76-1000μm, the wavelength boundary is not clearly defined and will be used to mean a wavelength region of 2.5μm or more in the present invention. Since the wavelength region is close to the natural frequency of the organic compound molecule existing in nature and easily resonates with it, it is well absorbed into the living body made of the organic polymer compound, thereby stimulating and activating the molecule in the living body. In other words, all materials differ in the mass of the constituent atoms, the bonding method, the arrangement state, the bonding force, etc., and thus have inherent frequencies and rotational frequencies. The wavelength range of 2.5-25μm is changed in the vibration state such as stretching and inclination of most molecules. The wavelength range of 25-100μm is activated by changing the rotational energy of the molecule.

As a material emitting such far-infrared rays at room temperature, there are ceramics mainly composed of silica sand. Artificial ceramic is a high purity alumina (Al ₂ O _3), silica (SiO _2), zirconia (ZrO _2), titanium (TiO ₂₎ etc. as a main component and a transition metal, an oxidizing agent ferric iron according to the application oxide (Fe ₂ O ₃ ), Manganese oxide (MnO ₂ ), copper oxide (CuO), calcium oxide (CaO), chromium oxide (Cr ₂ O ₃ ), etc., are added as subsidiary components, and mixed with plastic clay to be molded and manufactured. Clay, which is a far-infrared radiant of nature, varies in composition and content depending on the region, but commonly, alumina (Al ₂ O ₃ ), silica (SiO ₂ ), zirconia (ZrO ₂ ), titanium oxide (TiO ₂ ), ferric oxide ( Fe ₂ O ₃ ), calcium oxide (CaO), magnesium oxide (MgO), sodium oxide (Na ₂ O), potassium oxide (K ₂ O) and the like as main components. As mentioned above, the far-infrared radiation ceramics have adsorption, absorption, and bacillus action due to the porosity of the ceramics in addition to the activation action of the substance molecules caused by the far-infrared radiation, so as to adsorb heavy metals and fungi in water. As well as high hygroscopic properties, such as dehumidification, deodorization, mold prevention.

In the present invention, while considering the problems of the conventional filtration membrane, by using the action and properties of the far-infrared radiation ceramic, it is possible to selectively separate and purify the macromolecular organic compounds and heavy metals in air and water, and is convenient to store and use The object of the present invention is to provide a ceramic separator and a method of manufacturing the same, which are much simpler and less expensive than those of the conventional method.

The ceramic separator of the present invention for achieving the above object is a far-infrared radiation ceramic containing 0.1 to 5% by weight of a metal catalyst of manganese oxide, copper oxide, iron oxide, divalent and trivalent iron as a metal on the polyethylene nonwoven fabric It is characterized by being deposited and immobilized after coating with chitosan.

According to another aspect of the present invention, there is provided a method of preparing a ceramic separator, which comprises mixing a polyvinyl alcohol suspension of far-infrared radiation ceramics with a polyvinyl alcohol suspension of manganese, copper and iron compounds in a predetermined ratio, drying, and then drying at 1000 ° C. The above sintered body was made into a porous sintered body, and the porous far-infrared radiation ceramic and the polyurethane resin were suspended in dimethylformamide, and the suspension composition was coated on a polyethylene nonwoven fabric with a predetermined thickness to be deposited, and then the surface was dried. The surface-dried nonwoven fabric was immersed in water to replace the dimethylformamide in the composition with water and then taken out to complete dehydration drying. A polyvinyl alcohol aqueous solution containing divalent and trivalent iron was sprayed onto the dehydrated surface and then dried again. The dried nonwoven fabric is a chitosan solution obtained by deacetylating chitin. Coating and is characterized in that it comprises the step of drying and then immobilized with an alkali solution.

The ceramic separator of the present invention prepared as described above contains a small amount of water glass (Na ₂ O.nSiO ₂ ) in the polyvinyl alcohol suspension, and / or the divalent and 3 It is preferable to add potassium permanganate, tannin and / or ascorbic acid to the polyvinyl alcohol aqueous solution of iron, and spray coating them together so that at least one of these components is finally included in the ceramic separator.

The ceramic separator of the present invention has a similar principle of action as that of the far-infrared ceramic deodorant, which the inventor has applied for as patent application No. 92-24085, which contains manganese oxide, copper oxide, iron oxide, divalent and trivalent iron as metal catalysts. The far-infrared radiation ceramics were deposited on a polyethylene nonwoven fabric together with a polyurethane resin and then coated with a solution of chitosan deacetylated chitin, a shellfish shell component, and immobilized by treatment with an alkaline solution. Therefore, the ceramic separator of the present invention adsorbs impurities such as polymers and organic compounds by the pores thereof, and then decomposes and builds them by the action of far-infrared radiation ceramics and metal catalysts, and various metal ions are removed by chitosan coating on the surface. Therefore, only water and low molecular weight materials can pass through and be separated. In addition, the ceramic separator of the present invention is a mixture of far-infrared ceramic powder with a polymer resin and deposited on a nonwoven fabric, and then immobilized with chitosan, a cellulose-based polymer compound, so that the mechanical strength is high and chemically stable, and dried after use. It is convenient because it can shake off the accumulated impurities on the surface and reuse it, and it can be dried and stored as it is.

Hereinafter, the ceramic separator of the present invention and a manufacturing method thereof will be described in detail.

Far-infrared radiation ceramics used in the present invention is an artificial ceramic using alumina (Al ₂ O ₃ ) and silica (SiO ₂ ) as the main constituents, the composition of which is Al ₂ Si ₂ O ₅ (OH) ₄ , or Natural far-infrared radiation produced by the method for producing far-infrared radiation ceramic particles, filed with the date of 1989.7.21, published by the inventor of the present inventors dated 1989.7.21, and manufactured by the present invention. Ceramic may be used, or artificial ceramics and natural ceramics may be mixed and used.

Metal catalysts included in the structure of the far-infrared radiation ceramics include manganese oxide, copper oxide and ferric oxide. Among these, manganese oxide and copper oxide are added in the form of an oxide or in the form of a compound which becomes an oxide by firing, followed by a predetermined process, so that the manganese oxide and copper oxide are present in the ceramic structure. In the case of ferric oxide, it is added in the form of iron sulfate or the like and calcined to become ferromagnetic materials of α-Fe ₂ O ₃ and γ-Fe ₂ O ₃ to form a magnetic field in the ceramic structure. Meanwhile, divalent and trivalent iron is finally deposited in an ionic form in an aqueous solution of polyvinyl alcohol to promote redox reactions by exchanging electrons with each other in a magnetic field formed by α- and γ-Fe ₂ O ₃ .

Accordingly, a polyvinyl alcohol suspension of far-infrared radiation ceramics, a manganese and copper compound, and a polyvinyl alcohol suspension such as iron sulfate are mixed at a predetermined ratio, dried, and then calcined at 1000 ° C. or more to obtain porous sintered particles. In addition, it is preferable to add water glass (Na ₂ O.SiO ₂ ), which promotes the action of the metal catalyst and the adhesive action, to the aqueous polyvinyl alcohol solution.

To the porous sintered body, about 40 to 60% by weight of polyurethane resin is mixed, and 2 to 3 times by weight of dimethylformamide of these mixtures is added and suspended. In this case, in order to facilitate mixing and adhesion between the polyurethane resin and the far-infrared radiation ceramics, it is convenient to first mix the polyurethane resin with polyvinyl alcohol and then suspend by adding dimethylformamide and then mix the far-infrared radiation ceramics.

The suspension composition is coated on a polyethylene nonwoven fabric to have a thickness of about 0.5 to 2 mm after drying, and then left to stand for about 15 minutes to dry the surface to fix the shape. There is no particular limitation on the material of the nonwoven fabric here, but for example, polyethylene or polypropylene is included in preferred materials.

The nonwoven fabric coated with the surface dried composition is then immersed in water to replace the dimethylformamide in the composition with water. Here, the operation of dipping in water can be performed in two stages. First, submerse in cold water for about 30 minutes, replace most of dimethylformamide with water, and then soak for about 30 minutes in hot water at about 70 ℃ to completely replace the rest. It is convenient to let. After dimethyl formamide in the structure is completely substituted with water, it is taken out of water and dried dehydrated at 100 ° C. or lower to form desired pores.

A polyvinyl alcohol aqueous solution containing divalent and trivalent iron salts is sprayed onto the dehydrated surface and then dried at 100 ° C. or lower. At this time, it is preferable to dissolve potassium permanganate, tannin and / or ascorbic acid together in polyvinyl alcohol in order to promote the action of the metal catalyst and spray coating on the nonwoven fabric. In the present invention, the amount of the metal catalyst of manganese oxide, copper oxide, iron oxide, divalent and trivalent iron is controlled to be 0.1 to 5% by weight of the weight of the far-infrared radiation ceramic as a metal. If less than 0.1%, the catalytic action is insignificant. It is difficult to achieve the effect of, and if it is greater than 5%, it is not economical to increase the effect by increasing the amount, so it is used in the above range.

Next, chitin obtained by heating the crustacean shell in hydrochloric acid solution is deacetylated with water: nitric acid (60:40) to obtain a solution of chitosan. A small amount of phosphorus pentoxide and polyacrylic acid are added thereto, followed by heating, and then the coating is deposited on a non-woven fabric on which the ceramic is deposited so as to have a thickness of 1 to 0.05 μm after drying. Subsequently, the chitosan coating was fixed by treating with sodium hydroxide solution, followed by washing with water to completely remove sodium hydroxide and drying to prepare a ceramic separator of the present invention. At this time, the size of the pores can be adjusted according to the concentration of the sodium hydroxide solution, the concentration of 5 to 10% is preferred and the size of the pores is 0.4 to 0.5μm.

Manganese oxide, copper oxide, iron oxide, divalent and trivalent iron are impregnated in the porous ceramic structure through the process as described above, and preferably impregnated with sodium oxide, potassium permanganate, tannin and / or ascorbic acid. It is possible to produce a ceramic separator in which the far-infrared radiating ceramic is deposited in a polyethylene nonwoven fabric in a fixed state by a polyurethane resin and immobilized with chitosan.

The mechanism of action of the ceramic separator of the present invention prepared as described above is as follows.

That is, as described in the functional mechanism of the far-infrared radiation deodorant of the patent application No. 92-24085, which the inventor has filed before the present application, the wavelength range of 2 to 15 μm of the far-infrared radiation emitted from the far-infrared radiation ceramic is the atomic group of most organic compounds. Since these organic compounds coincide with the intrinsic absorption wavelength range of, these organic compounds easily absorb and resonate far infrared rays in the above range, and in the presence of a metal catalyst, the molecular structure can be converted into other new compounds. That is, since the metal catalyst is contained in the far-infrared radiation ceramic, the material activation action of the far infrared light and the activation energy lowering action of the metal catalyst occur together. In particular, the action is remarkable for free gas molecules having a relatively high energy state. As a result, organic compounds such as methane, nitrogen compounds such as ammonia, sulfur compounds such as hydrogen sulfide and sulfur oxides, and carbon monoxide contained in the contaminated air are adsorbed in the porous structure, and then, gas such as carbon dioxide, water vapor and nitrogen is absorbed. It is converted and released, so that it can function to purify the air. Moreover, the reactions are not only occurred at room temperature, but are continuously repeated through various interactions, which is fundamentally different from filtration by simple adsorption, and thus does not require long-term cleaning and replacement. In addition, the adsorptive removal of solid impurities such as dust by the porous ceramic structure also occurs at the same time.

When the ceramic separator of the present invention is applied to the separation and purification of liquids, not only solid impurities in the liquid are removed due to the porous structure of the ceramic separator, but particularly preferably, tannins impregnated in the far-infrared radiation ceramic structure are proteins and starches. These can be removed by forming metal salts and precipitates as well as organic substances such as gelatin and gelatin. In addition, iron, calcium, and magnesium ions are removed to soften hard water, and copper oxide impregnated in the far-infrared radiation ceramic structure combines with sulfuric acid ions in water to produce copper sulfate. In case of sterilization and microbial growth and reproduction can be suppressed. Organics present in sewage are usually hydrated and charged, and are stabilized at the equilibrium position of mutual attraction and electrical repulsive force, so that they can be precipitated and removed only by applying a coagulant to reduce the potential, using the ceramic separator of the present invention. This can reduce the amount of such flocculant. In addition, since the ceramic separator of the present invention deposits a far-infrared ceramic containing a metal catalyst on a nonwoven fabric and immobilizes it with chitosan, a hydrophilic polymer compound obtained from shellfish shell components, it has a high mechanical and chemical strength and is stable even when used in a high temperature liquid. Only water and low molecular weight materials can be selectively passed through while maintaining

In addition, since the ceramic separator of the present invention has repellency against impurities that accumulate on the surface during the filtration of gas or liquid, it can be removed by a simple method of drying and brushing, and can be reused many times. It is also economical because it can exhibit the same filtration efficiency even during reuse. In addition, after use, it can be dried and stored as it is, it is convenient.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are only examples of the present invention and the present invention is not limited thereto.

(Example)

Far-infrared radiant ceramic is added to its 5-fold aqueous 5% polyvinyl alcohol aqueous solution and suspended homogeneously. Manganese oxide, copper oxide, and ferric sulfate are likewise added to a 5-fold aqueous solution of 5% polyvinyl alcohol and homogeneously suspended, and a small amount of water glass (Na ₂ O.nSiO ₂ ) is added thereto. Mix the far-infrared radiation ceramic suspension and the suspension of the metal catalyst mixture with each other, but adjust the amount so that the amount of manganese and copper is 0.5% of the weight of the far-infrared radiation ceramic and the amount of iron in ferric oxide is 0.2% of the weight of the far-infrared radiation ceramic. To mix. The polyvinyl alcohol suspension is dried in a dryer at a temperature of 80 to 120 ° C., and then heated to about 900 ° C. and calcined for about 4 hours to form a porous far-infrared radiation ceramic sintered body containing a metal catalyst in its pores.

A small amount of a 5% polyvinyl alcohol aqueous solution is added to 300 g of the polyurethane resin, and about 1500 g of dimethylformamide is added and mixed. Then, about 500 g of the porous far-infrared radiation ceramic sinter prepared above is added and stirred to form a suspension. The suspension composition is coated on a polyethylene nonwoven fabric to have a thickness of about 1 mm after drying, and then left for about 15 minutes to allow the surface to dry.

The coated and dried polyethylene nonwoven fabric as above is first immersed in cold water for about 30 minutes and then soaked in warm water at about 70 ° C. for about 30 minutes to completely displace the dimethyl formamide in the composition with water. It is then taken out and completely dehydrated at a temperature of about < RTI ID = 0.0 > 100 C < / RTI >

Ferrous sulfate (FeSO ₄ ) and ferric chloride (FeCl ₃ ) are then dissolved in a 5% aqueous polyvinyl alcohol solution, and potassium permanganate, tannin and ascorbic acid are dissolved therein and sprayed onto the dried surface above 100 ° C. To dry.

Next, shellfish shells are placed in a 2% hydrochloric acid solution and heated to remove protein, calcium, and ash, followed by treatment with water: nitric acid (60: 40) to obtain a solution of chitosan, a deacetylate of chitin. A small amount of phosphorus pentoxide and polyacrylic acid was added thereto, heated, and cooled. This is coated on the non-woven fabric in which the ceramic is deposited so that the thickness after drying is 1 μm to be combined with the polyurethane resin. Subsequently, the mixture is washed with a 10% aqueous sodium hydroxide solution to which a small amount of ammonia water is added, neutralized and fixed, and then the sodium hydroxide is completely washed with water and dried to prepare a ceramic separator of the present invention.

1 is an enlarged photograph of the surface of the ceramic separator of the present invention, (a) is a 200 times magnification before performing filtration, (b) is a 300 times magnification after performing filtration. After filtration is performed, it can be seen that impurities are deposited on the surface of the ceramic separator as in (b).

2 is an enlarged photograph of the cross section of the ceramic separator of the present invention, (a) is a 2000 times magnification before chitosan coating, and (b) is a 3000 times magnification after chitosan coating. It can be seen that the surface of the separator is fixed by coating the chitosan solution.

In order to measure the effect of the ceramic separator of the present invention prepared as described above was performed the following performance test.

(Performance test)

(1) Far infrared radiation wavelength range identification test

In the test to determine the wavelength region in which the radiation from the ceramic membranes of the present invention, the temperature 100 ℃, as a result of 1.97mW / cm ² of measuring the irradiance at distance 300mm, and GE filter transmittance Hereinafter 1.7μm 0, 2- It was about 0.45 at 15 μm. As a result, it was found that the separator of the present invention emits far infrared rays in the wavelength range of 2-15 μm.

(2) life sewage purification effect test

In order to measure the effect of the ceramic separator of the present invention to purify domestic sewage, the results of measuring the BOD and COD before passing the sewage through the separator and after the first and second passes are shown in Table 1 below. It was.

TABLE 1

As can be seen in Table 1, the sewage that passed through the separator of the present invention was found to be purified to such a degree that the BOD and COD decreases remarkably and may be discharged as it is.

(3) Softening test of hard water

In order to measure the effect of the membrane softening the hard water of the present invention, the amount of Fe ⁺⁺ before and after passing the hard water through the membrane, and the amount of Ca ⁺⁺ and Mg ⁺⁺ is measured to determine the CaCO ₃ Converted to the values shown in Table 2 below.

TABLE 2

As shown in Table 2, before passing through the separator of the present invention, the hardness was relatively weak as 135, but after passing through the membrane, the hardness was 35 as the soft water (for reference, hardness was 0-75 mg / l is soft water, 75-150mg / l is relatively weak hard water, 150-300mg / l is hard water, and 300mg / l or more is very strong hard water). In addition, Fe ⁺⁺ removal efficiency was found to be very large.

(4) Purification effect test of factory wastewater

In order to measure the effect of the ceramic separator of the present invention on the purification of the plating plant wastewater, the wastewater (pH 1-2) is neutralized with NaOH to pH6.9-7.2 and a flocculant is added before and after passing through the separator. Each BOD, COD and various ion concentrations were measured and the results are shown in Table 3 below.

TABLE 3

As can be seen in Table 3, the wastewater passed through the separator of the present invention was found to be purified to such an extent that the concentrations of BOD, COD, and various harmful components were significantly lowered and discharged as it is.

As described above, the ceramic separator of the present invention contains a metal catalyst in the far-infrared radiation ceramic, is fixed with polyurethane, deposited on a polyethylene nonwoven fabric, and then immobilized with chitosan, which is stable and high in water or an organic solvent. It is hydrophilic with mechanical tensile strength and can selectively separate high molecular compounds, organic compounds and heavy metal oxides from sewage and polluted air. Therefore, the ceramic separator of the present invention is a very practical invention that can be used semi-permanently and conveniently for filtration and purification of air and liquid.

Claims (3)

A far-infrared radiation ceramic containing 0.1 to 5% by weight of metal catalysts of manganese oxide, copper oxide, iron oxide, divalent and trivalent iron as metal is deposited on polyethylene nonwoven fabric with polyurethane resin and coated with chitosan and immobilized. Ceramic separator. The ceramic separator according to claim 1, wherein the separator further contains at least one of sodium oxide, potassium permanganate, tannin, and ascorbic acid derived from water glass (Na ₂ O · nSiO ₂ ). A polyvinyl alcohol suspension of far-infrared radiation ceramics and a polyvinyl alcohol suspension of manganese, copper and iron compounds are mixed at a predetermined ratio, dried and calcined at 1000 ° C. or higher to obtain a porous sintered body, and the porous far-infrared radiation ceramics and polyurethane described above. The resin is suspended in dimethylformamide, the suspension composition is coated on a polyethylene nonwoven fabric with a predetermined thickness to be deposited, the surface is dried, the surface dried nonwoven fabric is immersed in water, the dimethylformamide in the composition is replaced with water, and then taken out. Completely dehydrated, polyvinyl alcohol aqueous solution containing divalent and trivalent iron was sprayed onto the dehydrated surface and then dried again, and chitosan solution deacetylated chitin was coated on the dried nonwoven fabric and alkali Immobilizing with a solution and then drying The process for producing a ceramic membrane that.