CN110614032A

CN110614032A - Preparation method of filter material

Info

Publication number: CN110614032A
Application number: CN201910916864.0A
Authority: CN
Inventors: 高麟; 陈慧; 任德忠
Original assignee: Intermet Technology Chengdu Co Ltd
Current assignee: Intermet Technology Chengdu Co Ltd
Priority date: 2019-09-26
Filing date: 2019-09-26
Publication date: 2019-12-27
Anticipated expiration: 2039-09-26
Also published as: CN110614032B

Abstract

The invention discloses a preparation method of a filter material. The filtering material comprises a physical filtering functional layer and a chemical filtering functional layer which are overlapped in front and back along a filtering direction, wherein the physical filtering functional layer comprises a first physical filtering layer and a second physical filtering layer, the first physical filtering layer and the second physical filtering layer are overlapped in front and back along the filtering direction, the first physical filtering layer is used for filtering solid particles in a substance to be filtered, the second physical filtering layer is used for filtering at least one volatile organic compound, and the second physical filtering layer comprises activated carbon; the preparation method of the filter material comprises the following steps: (1) scattering activated carbon powder on the surface of the chemical filtering functional layer or the first physical filtering layer to form a second physical filtering layer; (2) and forming a connecting layer which connects the first physical filtering layer and the chemical filtering functional layer and is positioned around the second physical filtering layer by glue spraying and/or ultrasonic wave compounding to obtain the filtering material. The method has simple process, can improve the air purification effect and prolong the service life of the chemical filtering functional layer.

Description

Preparation method of filter material

Technical Field

The invention relates to the technical field of filter material preparation, in particular to a preparation method of a filter material.

Background

The pollutants in the air are mainly divided into solid pollutants and gaseous pollutants. For solid pollutant (such as PM10, PM2.5) pollution in air, the solid pollutant is generally removed by physical filtration (namely, the separation of a specific object is realized by a physical mode); gaseous contaminants such as VOCs, i.e., organic gaseous substances, in the air are generally removed by chemical filtration, i.e., separation of particular objects is achieved by using the chemical properties of the substances.

The fine particulate matters (such as PM2.5) in the solid pollutants have great harm to the health of human bodies. In the removal of fine particles by physical filtration, a fibrous filter material (for example, glass fiber, PP fiber, PET fiber, expanded PTFE fiber, etc.) having high filtration efficiency and good air permeability is particularly commonly used. However, such materials are prone to bacterial attachment and growth on the fiber bundles during use, thereby causing secondary contamination.

Formaldehyde is a substance which is harmful to human bodies and is contained in gaseous pollutants. In the removal of formaldehyde by chemical filtration, the use of manganese dioxide in metal oxides as formaldehyde decomposition catalyst has been recognized as a viable and in some ways advantageous. Currently, manganese dioxide as a formaldehyde decomposition catalyst is limited to nano-sized manganese dioxide, so that the specific surface area is sufficient to achieve acceptable formaldehyde removal efficiency of the formaldehyde decomposition catalyst. The service life of the existing formaldehyde decomposition catalytic filter device is usually short, and besides the service life of the formaldehyde decomposition catalyst, one of the main reasons is caused by the fact that the formaldehyde decomposition catalyst falls off from the air-permeable support body.

Since air often contains different kinds of pollutants at the same time, in order to remove the pollutants, the filtering devices with different filtering objects are usually connected in series to form a filtering system. The filtering system can be formed by independent filtering devices or integrated by the filtering devices. When the filter system is integrated by filter devices, the filter materials, which are respectively different filter devices, are not to be mounted relatively independently in the same housing part, nor to be assembled with each other as relatively independent parts.

In the prior art, when the filter materials as different filter devices are independently installed in the same shell member, the filter materials are generally compounded by directly overlapping or adhering the filter materials. The directly overlapped filtering materials have gaps, so that the flow resistance of the object to be filtered is large due to the disturbance of the gaps on the object to be filtered during filtering, and the object to be filtered can swing or collide under the action of the object to be filtered, so that the structural stability is reduced, and the service life and the use effect are influenced. When the adhesion bonding is used, a viscose bonding surface or a sintered bonding surface is usually formed at the interface between the functional layers attached to each other, which may have a certain barrier effect against the flow of the substance to be filtered, thus increasing the filtration resistance.

Disclosure of Invention

The first aim of the invention is to provide a filter material, which solves the problem of high filter resistance caused by improper compounding of the filter material in the prior art, optimizes the composite structure of different functional layers in the filter material in the second aspect, and solves the technical problem of loss of function caused by falling off of a catalyst for chemisorption of gas pollutants in the third aspect. A second object of the present invention is to provide a filter assembly and a filter, also to solve the above technical problems. A third object of the present invention is to provide a method for producing a filter material so as to obtain a composite filter material that does not affect the filtration resistance.

To achieve the first object, a first filter material is provided. The filter material has different functional layers, wherein all the functional layers comprise a physical filter functional layer and a chemical filter functional layer, and the physical filter functional layer and the chemical filter functional layer are overlapped front and back along the filter direction; the chemical filtering functional layer comprises a chemical filtering layer for filtering at least one volatile organic compound; the physical filtering functional layer comprises a first physical filtering layer for filtering solid particles in a substance to be filtered; the filter material also comprises a connecting layer for connecting two adjacent functional layers.

Further, the chemical filter layer is a formaldehyde decomposition catalytic felt, and the formaldehyde decomposition catalytic felt comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; preferably, the formaldehyde decomposition catalyst consists essentially of MnO of the delta crystalline form₂Formed into submicron-micron petal-shaped particles.

Further, the first physical filter layer is a fiber filter layer or a metal filter layer; or the first physical filter layer is formed by overlapping a metal filter layer and a fiber filter layer, and a connecting layer is arranged between the metal filter layer and the fiber filter layer.

Furthermore, the physical filtering function layer also comprises a second physical filtering layer for filtering at least one volatile organic compound, and the first physical filtering layer and the second physical filtering layer are overlapped front and back along the filtering direction; the second physical filter layer comprises activated carbon.

Furthermore, the second physical filter layer is formed by stacking activated carbon powder, and the connecting layer between the physical filter function layer and the chemical filter function layer is arranged between the first physical filter layer and the chemical filter layer and surrounds a stacking space of the activated carbon powder.

Further, all the functional layers comprise a protective functional layer, the chemical filtering functional layer and the protective functional layer are overlapped front and back along the filtering direction, and the protective functional layer has a porous structure and the aperture is smaller than the particle size of the catalyst in the chemical filtering layer; preferably, the protective functional layer is a PP fiber felt, a PET fiber felt or an electrostatic cotton.

Further, the connecting layer is a rubber silk layer and/or an ultrasonic composite layer.

Furthermore, the glue silk layer comprises a plurality of layers of glue silk units distributed from top to bottom, and the deposition directions of two adjacent layers of glue silk units are different; the glue silk unit is formed by arranging glue silk with the diameter less than or equal to 0.1mm according to a certain distance.

Furthermore, the ultrasonic composite layer is composed of one or more ultrasonic composite lines, and the ultrasonic composite lines are formed by arranging composite nodes with the length of less than or equal to 3mm and the width of less than or equal to 1mm at intervals of 1-3 mm.

A second filter material is provided for achieving the first object described above. The filter material has different functional layers, wherein all the functional layers comprise a chemical filter functional layer and a protective functional layer, and the chemical filter functional layer and the protective functional layer are overlapped front and back along the filter direction; the chemical filtering functional layer comprises a chemical filtering layer for filtering at least one volatile organic compound; the protective function layer has a porous structure and the pore diameter is smaller than the particle size of the catalyst in the chemical filter layer.

Further, the protective function layer is PP fiber felt, PET fiber felt or electrostatic cotton.

Further, all the functional layers further comprise a physical filtering functional layer, and the physical filtering functional layer and the chemical filtering functional layer are overlapped front and back along the filtering direction; the physical filtering function layer comprises a first physical filtering layer for filtering solid particles in a substance to be filtered and/or a second physical filtering layer for filtering at least one volatile organic compound, and when the physical filtering function layer is provided with the first physical filtering layer and the second physical filtering layer at the same time, the first physical filtering layer and the second physical filtering layer are overlapped front and back along the filtering direction.

Further, the first physical filter layer is a fiber filter layer or a metal filter layer; or the first physical filtering layer is formed by arranging a metal filtering layer and a fiber filtering layer in front and at back along the filtering direction; the second physical filter layer comprises activated carbon.

Further, the filter material also comprises a connecting layer for connecting two adjacent functional layers.

Furthermore, the symmetrically distributed connecting layers are only arranged locally between two adjacent functional layers.

A third filter material is provided for achieving the first object described above. The filter material has different functional layers, wherein all the functional layers comprise a physical filter functional layer and a chemical filter functional layer, and the physical filter functional layer and the chemical filter functional layer are overlapped front and back along the filter direction; the chemical filtering functional layer comprises a chemical filtering layer for filtering at least one volatile organic compound; the physical filtering functional layer comprises a second physical filtering layer for filtering at least one volatile organic compound; the filter material also comprises a connecting layer for connecting two adjacent functional layers.

Furthermore, the physical filtering function layer further comprises a first physical filtering layer for filtering solid particles in the object to be filtered, and the first physical filtering layer and the second physical filtering layer are overlapped front and back along the filtering direction.

Further, the first physical filter layer is a fiber filter layer or a metal filter layer; or the first physical filtering layer is composed of a metal filtering layer and a fiber filtering layer which are arranged in front and at the back along the filtering direction, and a connecting layer is arranged between the metal filtering layer and the fiber filtering layer.

The three filter materials have the following advantages: (1) by arranging the connecting layer, the problem that the resistance of the object to be filtered is increased due to the disturbance of the object to be filtered with larger clearance can be avoided, so that the filtering process is more stable; the resistance of the object to be filtered can be reduced by at least 30 percent through verification; (2) by arranging the connecting layer, a plurality of functional layers can be compounded into a whole, and the problem of damage caused by shaking and mutual collision of the functional layers is avoided; (3) by arranging the protective function layer, the catalyst falling off from the chemical filter layer can be intercepted, and the service life of the catalyst is prolonged; the service life of the chemical filter layer can be prolonged by 30 percent through verification; (4) the protective functional layer can also support the functional layer positioned in front of the protective functional layer in the filter material along the direction opposite to the filtering direction; (5) the two functional layers which are used for filtering at least one volatile organic compound, specifically the second physical filtering layer and the chemical filtering layer, are arranged, so that the purification is more thorough, and the second physical filtering layer is placed in front of the chemical filtering layer, so that the probability of catalyst poisoning in the chemical filtering layer can be reduced, and the service life of the catalyst is further prolonged; (6) the functional layers are connected into a whole through the connecting layer, so that the functional layers can be mutually supported, the use of a positioning component and/or a supporting component during the installation of the filter material is reduced, and the occupied space of the filter material is favorably reduced.

The glue silk layer be by superfine hot melt adhesive silk be unordered form distribution or be certain interval distribution and constitute, consequently different with the glue film of fine and close distribution, the glue silk layer of this application has connection effect and air permeability concurrently. The verification proves that when the glue silk with the diameter less than or equal to 0.1mm is adopted, the influence on the air permeability of the filtering material can be ignored.

The principle of ultrasonic compounding is that high-frequency vibration waves are transmitted to two or more material surfaces, and the material surfaces are rubbed with each other under pressure to form fusion between molecular layers. The ultrasonic composite line is composed of very small composite nodes, so that the influence on the air permeability of the filter material is small; when the ultrasonic wave composite line is formed by arranging composite nodes with the length less than or equal to 3mm and the width less than or equal to 1mm at intervals of 1-3 mm, the influence on the air permeability of the filtering material can be ignored.

The glue silk layer compares with the ultrasonic wave composite bed, and the acquirement on glue silk layer is quicker, but the connected mode on glue silk layer belongs to physical connection, and the fusing layer is connected two functional layers as an organic whole through the chemical bond, has better cohesion, more helps promoting the stability of filtering material in the use.

In order to further reduce the influence of the tie layer on the permeability of the filter material, a symmetrically distributed tie layer is preferably provided only locally between two adjacent functional layers. When ultrasonic compounding is employed, even if it is provided only locally, since the ultrasonic composite layer is formed under pressure, a gap between contact surfaces of adjacent functional layers where the ultrasonic composite layer is not provided can be ignored. When the colloid silk layer is adopted, the thickness of the colloid silk layer can be controlled to be less than 50 μm, so that the functional layer gap without the colloid silk layer is very small, and the disturbance of the gap to be filtered can be ignored. And because the connecting layer is evenly distributed, the stress of the filtering material is more even in the use process, and the shaking and the mutual collision of the functional layers of the filtering material can be further reduced. Simultaneously, because the clearance is very little, consequently the collision dynamics between the functional layer is little, not fragile functional layer. When the connection layer is provided locally, in order to ensure the connection function, it is preferable that the width of the connection layer is 3 to 6cm, and the length is not less than 1/3 times the length (the connection layer is provided along the length direction of the filter material) or the width (the connection layer is provided along the width direction of the filter material) of the filter material.

In the above three filter materials, it is preferable that the first physical filter layer is composed of a metal filter layer and a fiber filter layer which are overlapped in the front and back direction in the filter direction; such an arrangement has the following effects: (1) because the metal filter layer is mostly conductive, the metal filter layer can be used as a conductive layer, so that when the metal filter layer is charged by an external power supply, the metal filter layer can repel or adsorb charged particles in a substance to be filtered, thereby improving the filtering efficiency of the filtering material; meanwhile, since most of the fiber filter layers have an insulating property, when the metal filter layer also serves as a conductive layer, the fiber filter layer may serve as an insulating layer for the conductive layer, so as to connect the metal filter layer to a housing and/or other components (e.g., other functional layers of the filter material) on which the filter material is mounted in an insulating manner. (2) When the metal filter layer is also used as the conductive layer and the fiber filter layer is used as the insulating layer of the conductive layer, the fiber filter layer plays an insulating role between the metal filter layer and the chemical filtering function layer, so that the adverse effect of the electrification of the metal filter layer on the catalyst in the chemical filtering function layer can be avoided, for example, the catalytic activity is reduced due to the influence of the electrification of the metal filter layer on the electronic structure on the surface of the catalyst; in addition, no matter whether the metal filter layer is externally connected with a power supply or not, the surface of the metal filter layer may have certain charges, and if the fiber filter layer is set to be a fiber filter layer with electrical insulation property, the adverse effect of the surface charges of the metal filter layer on the catalyst can be avoided; (3) the filter material is firstly filtered by the metal filter layer for the first time and then filtered by the fiber filter layer for the second time, so that the number of microorganisms such as bacteria entering the fiber filter layer is reduced, the condition that the bacteria are attached to and bred in the fiber filter layer is reduced, the metal filter layer has relatively good bacteriostatic performance, and the bacteria are not easy to breed, so that the problem that the bacteria are bred in the whole filter material can be improved to a certain degree.

When the filter material has a metal filter layer and a fiber filter layer, the filtering method comprises the following steps: controlling the electrification mode of the metal filter layer according to the pollutant components in the air to be filtered: when the content of the solid particles in the air rises to a set threshold and/or the content of the volatile organic compounds in the air falls to the set threshold, the metal filter layer is electrified, and when the content of the solid particles in the air falls to a set threshold and/or the content of the volatile organic compounds in the air rises to the set threshold, the metal filter layer is uncharged.

The metal filter layer is mainly made of metal (including alloy). The metal filter layer is preferably a metal filter layer mainly composed of a powder sintered metal porous material; more preferably a flexible metal film having a thickness of 200 μm or less and being foldable. The thickness of the flexible metal film is less than or equal to 200 mu m, so that higher air permeability is easier to achieve. Since the flexible metal film is foldable by itself, the bending or folding of the shape of the filter material is not affected. The flexible metal film can be a porous film prepared by the method provided in chinese patent document CN104874798A, or a flexible metal film prepared by other methods. The present application proposes in particular to use a product manufactured by the applicant of the present application on the basis of the content of the above-mentioned CN104874798A patent document under the commercial name "paper type film". The paper-type film is a flexible metal film containing a net-shaped framework and a powder sintered metal porous material filled in meshes of the framework, the thickness of the paper-type film can reach less than or equal to 200 mu m, and the paper-type film can be folded.

The average pore diameter of the paper-type membrane (or other metal filter layer) is generally set in the range of 5 to 200 μm. The upper limit of the range may be set to 190. mu.m, 180. mu.m, 170. mu.m, 160. mu.m, 150. mu.m, 140. mu.m, 130. mu.m, 120. mu.m, 110. mu.m or 100. mu.m, as required; the lower limit of the range may be set to 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm or 100 μm as required. In order to balance the air permeability and the filtering efficiency of the metal filter layer, the average pore size of the metal filter layer may be generally 10 to 150 μm, more preferably 10 to 120 μm, still more preferably 10 to 100 μm, and still more preferably 10 to 80 μm. When the filter material contains the chemical filter function layer, the average pore diameter of the metal filter layer can be properly increased in consideration of the influence of the chemical filter function layer on the whole air permeability of the filter material. For example, when the filter material is composed of a metal filter layer, a fiber filter layer, a formaldehyde decomposition catalyst felt and a protective function layer, the average pore diameter of the metal filter layer is set to be 40 to 90 μm, specifically, about 42 μm, about 55 μm, 79 μm and 85 μm, and the like, and at this time, the effect of using these metal filter layers is satisfactory.

The term "average pore size" as used above, is a common parameter characterizing porous materials and can be measured by the bubble method. The related art referred to in patent application publication No. CN104266952A filed by the applicant of the present application may be the same as measuring the average pore size of the metal filter layer. The term "filtration efficiency" as used above, means the ratio of the amount of solid particles intercepted by the filter material to the amount of solid particles contained in the gas to be filtered itself, under the conditions tested.

The metal filter layer can contain some metal substances with sterilization function, such as copper, silver and the like. Therefore, the powder sintered metal porous material of the metal filter layer is preferably made of copper-nickel alloy formed by powder sintering, and the metal filter layer can meet the requirement of flexibility and has a certain sterilization function.

The fiber filter layer is mainly made of inorganic nonmetallic fibers (such as glass fibers), organic fibers (such as PP fibers) or composite materials thereof. Typically, the fibrous filter layer is composed of at least one fibrous filter material selected from the group consisting of glass fibers, PP fibers, PET fibers, and expanded PTFE fibers. Generally, the filtration efficiency of the fiber filtration layer for solid particulates is higher than the filtration efficiency of the metal filtration layer for solid particulates. The fiber filter layer is preferably a fiber filter layer mainly composed of a microfiber filter material, so that the fiber filter layer can have better filtering efficiency and air permeability. The term "microfibre filter material" is understood to mean: the diameter of the fiber filtering layer can ensure that the removal rate of dust with the particle size of more than or equal to 2.5 mu m in the gas to be filtered is more than 98 percent. The glass fiber, the PP fiber, the PET fiber and the expanded PTFE fiber can be superfine fiber filter materials. When the fiber filter layer is mainly composed of a microfiber filter material, it is preferable that the average pore size of the metal filter layer is selected to be 10 to 100 μm, and it is particularly preferable that the average pore size of the metal filter layer is selected to be 20 to 80 μm.

Empirically, the filtration accuracy of a porous filter media is approximately equal to 1/10, the average pore size. For example, when the average pore size of the metal filter layer is 80 μm, the filtration accuracy is about 8 μm. Furthermore, during filtration, a filter cake is gradually formed on the metal filter layer, so that the filtration precision is further increased, namely the filtration precision is less than 8 μm. That is, when the average pore diameter of the metal filter layer is 80 μm, it can intercept solid particles (dust) having a particle size of 8 μm or less at the time of filtration. That is, when the average pore size of the metal filter layer is selected to be 10 to 100 μm, the metal filter layer can intercept a large part of solid particles with large particle size such as PM10, a large part of mold spores (the particle size distribution range in the air is mainly 1 to 100 μm), and a part of bacteria (the particle size distribution range in the air is mainly 0.5 to 10 μm). Therefore, the conditions of mould and bacteria attached to and bred on the fiber filter layer can be effectively reduced. However, as the average pore diameter of the metal filter layer is closer to the lower limit of 10 to 100 μm, the air permeability of the entire filter material including the metal filter layer and the fibrous filter layer and further including other functional layers is lower. Therefore, it is better to select the relevant technical parameters such as the average pore diameter of the metal filter layer according to the overall filtering performance index of the filter material.

To achieve the second object, according to one aspect of the present invention, a filter assembly is provided. The filter assembly includes a filter portion that employs one of the three filter materials described above.

The filter assembly is designed in a specific manner for the application of the above-described filter material to configure the filter material as a single, self-contained module that is integrally removable from parent equipment, such as filters, to facilitate individual manufacture, sale, installation and replacement of the filter assembly. The filter component further comprises a positioning portion and a sealing portion, the positioning portion comprises a positioning frame which is arranged on the periphery of the filter material and limits the filter material in the positioning frame and is open to the outside of two sides of the filter material, and the sealing portion comprises a sealing material which is arranged between the filter material and the positioning portion and used for preventing the object to be filtered from penetrating through the inner boundary area of the positioning frame without passing through the filter material.

Furthermore, the positioning part is provided with a conductive part which is used for being in conductive connection with the metal filter layer in the filter material; the metal filter layer is mounted in the filter assembly in an insulated manner and can be charged by the conduction of the conductive member. Thus, the metal filter layer can be mounted in the filter assembly in an insulated manner and can be charged by the electrical conduction of the electrically conductive member. The conductive member may be any conductor that is located on the positioning portion and is preferably arranged so as to be automatically brought into contact with an electrical connection terminal on a parent device such as a filter after the filter assembly is mounted on the parent device.

Furthermore, the sealing material of the sealing part can be a sealant directly adhered between the periphery of the filtering material and the positioning frame, and can also further comprise a sealing plate positioned at the edge of the filtering material, the inner side surface of the sealing plate is adhered to the surface where the corresponding edge of the filtering material is positioned through the sealant, and the outer side surface of the sealing plate is adhered to the inner side surface of the corresponding positioning frame through the sealant. Therefore, the sealing plate and the filtering material can be bonded at first and then the filtering material bonded with the sealing plate is hermetically installed in the positioning frame, so that the filtering material can be conveniently and hermetically installed in the positioning frame through the sealing plate. However, the provision of a sealing plate increases the manufacturing cost of the filter assembly and takes up some space.

Furthermore, the filter material is provided with a corrugated structure with a rectangular shape, one pair of opposite sides of the filter material are corrugated edges, and the other pair of opposite sides of the filter material are straight edges; the positioning frame is a rectangular positioning frame matched with the filtering material, the surface of the filtering material where the linear edges are located is directly bonded with the inner side surface of the corresponding positioning frame through sealant, and the folded wavy edges are bonded with the inner side surface of the corresponding positioning frame through the at least one sealing plate. Compared with the filter material with a smooth surface, the filter material with the fold-shaped structure can greatly improve the filter area of the filter material, thereby improving the filter efficiency. At the moment, the surface of the filter material where the straight-line-shaped edge is located is directly bonded with the inner side surface of the corresponding positioning frame through the sealant, and the folded wave-shaped edge is bonded with the inner side surface of the corresponding positioning frame through the at least one sealing plate. Therefore, the purpose of conveniently and hermetically installing the filtering material in the positioning frame is achieved through the sealing plate, the corrugated edges can be effectively sealed, in addition, the using amount of the sealing plate is also saved, and in addition, the filtering material with the linear edges is bonded with the corresponding inner side surface of the positioning frame in a face-to-face mode, so that a good sealing effect can be achieved. When the filter material has the fold-shaped structure, the protective function layer can intercept the catalyst falling off from the chemical filter layer and support the function layer in front of the protective function layer in the filter material along the direction opposite to the filtering direction, and the fold-shaped structure can be positioned and shaped, so that the fold waves can be prevented from deforming to a certain extent to avoid the inconsistency of gaps among the fold waves.

Further, the positioning frame includes: the side positioning frame body is provided with a sealing material between the side positioning frame body and the filtering material; the upper positioning frame body is arranged at the upper end of the side positioning frame body and extends along the top edge of the side positioning frame body; and a lower positioning frame body which is arranged at the lower end of the side positioning frame body and extends along the bottom edge of the side positioning frame body. Thereby, a better fixation and sealing of the filter material is achieved. Preferably, the upper positioning frame body is connected with the side positioning frame body in a split mode, so that the upper positioning frame body is installed on the side positioning frame body after the filter material is installed in the positioning frame body. Preferably, the bottom surface of the upper positioning frame body is designed to be a step surface adapted to the upper end of the side positioning frame body, and the sealant between the upper positioning frame body and the side positioning frame body is substantially distributed on two parallel planes on the step surface, so that the upper positioning frame body can be conveniently installed and positioned, and the sealing effect of the upper positioning frame body on the filter material can be ensured. The upper positioning frame body and the lower positioning frame body can limit the filtering materials and limit the filtering materials in the side positioning frame body better.

Further, the positioning portion of the filter assembly may include a pleat-forming member disposed on a side of the filter material, and the pleat-forming member may include a support disposed at intervals between pairs of adjacent pleat waves of the filter material. Although the filter material with the pleated structure can greatly increase the filtering area of the filter material compared with the filter material with a smooth surface, thereby improving the filtering efficiency, the pleated waves of the pleated structure may deform during the use process, resulting in inconsistent gaps between the pleated waves and finally resulting in uneven filtering flux distributed on the filter material. The support objects which are arranged on the pleat shape-keeping component at intervals between a plurality of pairs of adjacent pleat waves of the filter material prevent the pleat waves from deforming, thereby ensuring the uniformity of the filter flux distributed on the filter material. Preferably, the support is made of positioning glue which is respectively filled between the adjacent fold waves and solidified, so that the formed support is low in cost, convenient to manufacture and capable of being bonded with the fold waves without falling off easily. Further preferably, the positioning glue is only filled between the wave crests of the adjacent fold waves, so that the laying area of the positioning glue on the filter material is reduced, and the influence of the positioning glue on the filter efficiency is reduced; the depth of the positioning glue filled in the gaps between the wave crests of the corresponding adjacent fold waves is preferably not more than 1.5cm, 1.2cm, 1cm, 0.8cm or 0.5 cm. The depth of the positioning glue filled in the gaps between the wave crests of the corresponding adjacent fold waves is related to the characteristics of the filter material and the like. For example, when the filter material is relatively soft, the positioning glue is not easily filled only between the peaks corresponding to the adjacent corrugation waves, respectively, because it is difficult for the positioning glue to function as an effective support for the corrugation waves. When the metal filter layer is provided, since the metal filter layer has high resistance to deformation, and the metal filter layer is preferably a metal filter layer mainly composed of a powder sintered metal porous material and has a desired surface roughness so that the positioning glue is provided on the surface of the metal filter layer to achieve the effect that the positioning glue is filled only between the peaks corresponding to the adjacent corrugation waves, respectively. The positioning glue can also form a continuous positioning glue thread on the side surface of the filtering material, and in this case, the fold shape-keeping component can comprise at least two positioning glue threads which are not overlapped with each other and are arranged on the side surface of the filtering material.

To achieve the second object, according to one aspect of the present invention, a filter is provided. This filter includes air intake, air exit and is located the wind channel between air intake and the air exit, install one of above-mentioned three kinds of filter assembly on the wind channel, filter assembly's windward side switches on with the air intake, goes out the wind side and switches on with the air exit.

Further, the filter doubles as an air conditioner having an air filtering function. Due to the special structure of the filter material, the thickness of the filter assembly is thin, and the filter assembly can be directly installed in the existing household air conditioner.

In order to achieve the third object, a method for producing a filter material is provided. The filtering material comprises a physical filtering functional layer and a chemical filtering functional layer which are overlapped front and back along a filtering direction, wherein the physical filtering functional layer comprises a first physical filtering layer and a second physical filtering layer, the first physical filtering layer and the second physical filtering layer are overlapped front and back along the filtering direction, the first physical filtering layer is used for filtering solid particles in a substance to be filtered, the second physical filtering layer is used for filtering at least one volatile organic compound, and the second physical filtering layer comprises activated carbon; the preparation method of the filter material comprises the following steps:

(1) scattering activated carbon powder on the surface of the chemical filtering functional layer or the first physical filtering layer to form a second physical filtering layer;

(2) and forming a connecting layer which connects the first physical filtering layer and the chemical filtering functional layer and is positioned around the second physical filtering layer by glue spraying and/or ultrasonic wave compounding to obtain the filtering material.

When the filter material has a pleated structure, the method for manufacturing the filter material should further include the step (3) of integrally deforming and processing the blank of all the functional layers of the stacked filter material into a filter material of a specific shape.

Further, the particle size of the activated carbon powder is 0.01-5 mm, preferably 0.03-1 mm, and further preferably 0.05-0.3 mm. The smaller the particle size of the activated carbon particles, the higher the bulk density and the larger the specific surface area, but the more the airflow resistance increases, so the most preferable particle size of the activated carbon particles is 0.05 to 0.3mm in consideration of the airflow resistance and the adsorption efficiency.

Further, the method also comprises the step of scraping and compacting the activated carbon powder accumulation layer. In order to control the surface deformation of the first physical filter layer and the chemical filter function layer caused by the uneven surface of the second physical filter layer, the second physical filter layer is leveled by scraping and compacting the active carbon powder accumulation layer, the second physical filter layer is in closer contact with the first physical filter layer and the chemical filter function layer, the active carbon powder does not slide in use, and the leveled surface can be maintained all the time.

Further, the first physical filter layer is a fiber filter layer or a metal filter layer; or the first physical filtering layer consists of a metal filtering layer and a fiber filtering layer which are overlapped front and back along the filtering direction, and a connecting layer formed by spraying glue and/or ultrasonic wave compounding is arranged between the metal filtering layer and the fiber filtering layer.

Further, all the functional layers comprise a protective functional layer, the chemical filtering functional layer and the protective functional layer are overlapped front and back along the filtering direction, a connecting layer formed by glue spraying and/or ultrasonic wave compounding is arranged between the chemical filtering functional layer and the protective functional layer, the protective functional layer has a porous structure, and the aperture of the protective functional layer is smaller than the particle size of the catalyst in the chemical filtering functional layer.

The method further comprises the step of using a lapping strip with the thickness matched with that of the second physical filtering layer, wherein the lapping strip is positioned between the first physical filtering layer and the chemical filtering functional layer and encloses a placing space of the activated carbon powder, and the upper surface and the lower surface of the lapping strip are respectively in composite connection with the first physical filtering layer and the chemical filtering functional layer through glue spraying and/or ultrasonic waves; preferably, the overlapping strip has a porous structure. Because the active carbon powder accumulation layer has a certain thickness, if the first physical filter layer and the chemical filtering functional layer are connected in a composite mode through ultrasonic waves, if the accumulation layer is thick, the surfaces of the first physical filter layer and the chemical filtering functional layer can deform to a certain extent. Through the arrangement of the lap joint strip, the supporting function of the lap joint strip can reduce the surface deformation amount generated by the partition of the second physical filter layer when the first physical filter layer is connected with the chemical filter function layer. When adopting the overlap joint strip, can spill into activated carbon again after chemical filtration functional layer or first physical filter layer surface installation overlap joint strip, it is more convenient to operate like this, and can also be convenient for carry out strickle and compaction operation to activated carbon powder pile layer.

Further, the method also comprises the step of using a mold for preventing the activated carbon powder from falling into the connecting layer, wherein the mold is provided with through holes matched with the size of the second physical filter layer. In order to place the activated carbon more efficiently and prevent the activated carbon from falling into the joint of the first physical filter layer and the chemical filter layer, a mold can be adopted for assistance, the mold has a through hole matched with the second physical filter layer in shape and thickness, and therefore, the activated carbon can be directly scattered into the through hole. When adopting the mould, except preventing that the active carbon from falling into the junction of first physical filtration layer and chemical filter layer, can also be convenient for carry out strickle and compaction operation to active carbon powder bed-up.

Furthermore, the connecting layers of each butt joint surface are a plurality of and are symmetrically distributed.

Furthermore, a connecting layer formed by spraying glue is a glue wire layer, the glue wire layer comprises a plurality of layers of glue wire units distributed from top to bottom, and the deposition directions of two adjacent layers of glue wire units are different; the glue silk unit is formed by arranging glue silk with the diameter less than or equal to 0.1mm according to a certain distance; the width of the rubber silk layer is 3-6 cm.

Furthermore, the connecting layer formed by ultrasonic wave compounding is an ultrasonic wave composite layer, the ultrasonic wave composite layer is composed of one or more ultrasonic wave composite lines, and the ultrasonic wave composite lines are formed by arranging composite nodes with the length being less than or equal to 3mm and the width being less than or equal to 1mm at intervals of 1-3 mm.

In the preparation method, in order to control the surface deformation amount generated by the partition of the second physical filter layer when the first physical filter layer is connected with the chemical filter function layer, if the lap joint strip is not adopted, the chemical filter layer and the first physical filter layer can be connected by adopting the adhesive thread layer matched with the thickness of the second physical filter layer. The thickness of the glue silk layer can be controlled by controlling the number of the glue silk units. In order to sufficiently reduce surface deformation of the first physical filtration layer and the chemical filtration layer, it is preferable that the thickness of the silk layer is equal to that of the second physical filtration layer. While the thickness of the layer of glue threads should be sufficiently thin between the other functional layers. Of course, it is also possible to place the activated carbon in a rectangular parallelepiped frame having openings, and then connect the upper and lower surfaces of the rectangular parallelepiped frame with the chemical filter layer and the first physical filter layer, respectively, but this would tend to increase the volume and weight of the filter material to a great extent.

The technical scheme of the formaldehyde decomposition catalyst, the formaldehyde catalytic decomposition felt and the manufacturing method thereof which are very suitable for the technical scheme is as follows:

formaldehyde decomposition catalyst consisting essentially of MnO of the delta crystal form₂Formed into submicron-micron petal-shaped particles. The submicron-micron petal-shaped particles refer to the combination of submicron petal-shaped particles with the diameter ranging from 0.1 to 1 mu m and micron petal-shaped particles with the diameter ranging from 1 to 10 mu m. Generally, the diameter distribution range of the submicron-micron petal-shaped particles is more than or equal to 0.5 μm. I.e. the diameter of the largest micron-sized petal-shaped particle of these submicron-micron-sized petal-shaped particles is at least 0.5 μm larger than the diameter of the smallest submicron-sized petal-shaped particle.

Furthermore, the diameters of the submicron-micron petal-shaped particles are mainly distributed between 0.1 and 5 microns, and more specifically, the diameters of the submicron-micron petal-shaped particles are mainly distributed between 0.3 and 5 microns. Furthermore, the diameters of the submicron-micron petal-shaped particles are mainly distributed between 0.5 and 5 mu m; still further, the diameters of the submicron-micron petal-shaped particles are mainly distributed between 0.5 and 3 microns.

Further, the water washing liquid of the submicron-micron petal-shaped particles is alkaline.

The formaldehyde catalytic decomposition felt comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support, wherein the formaldehyde decomposition catalyst is any one of the formaldehyde decomposition catalysts.

Further, the formaldehyde decomposition catalyst is distributed outside the material constituting the air-permeable support and is mainly filled in the pores between the materials constituting the air-permeable support.

Further, a binder distributed on the formaldehyde decomposition catalyst; the adhesive is preferably, but not limited to, an acrylic adhesive or a polyurethane adhesive.

Further, when the relative adhesion amount of the formaldehyde decomposition catalyst to the air-permeable support is defined as the ratio of the weight of the formaldehyde decomposition catalyst divided by the area of the windward surface of the air-permeable support, the relative adhesion amount is 40g/m²The above.

Furthermore, the air permeability of the air-permeable support is more than or equal to 3000m under the pressure difference of 100Pa³/m²H, preferably an air-permeable fiber mat having a permeability to air of at least 5500m at a pressure difference of 100Pa³/m²H air-permeable fiber mats; and the relative adhesion amount is 40 to 120g/m²Preferably 50 to 70g/m²。

Further, the breathable support is made of PP fiber felt or PET fiber felt.

Further, the air-permeable support adopts a foam-shaped porous support body or a support net; when the breathable support adopts a support net, the support net can be any one of a woven net, a punched net and a diagonal net.

The formaldehyde decomposition catalyst and the formaldehyde catalytic decomposition felt applying the formaldehyde decomposition catalyst relate to MnO with specific crystal form, micro-morphology, diameter size and diameter distribution₂Particles of the MnO₂The particles are obtained based on a large-scale production process developed by the applicant, the process not only greatly improves the production efficiency of the formaldehyde decomposition catalyst, but also obtains the product, namely the formaldehydeThe formaldehyde removing effect of the decomposition catalyst also breaks through expectations, and compared with other existing formaldehyde decomposition catalysts, the formaldehyde removing catalyst has ideal formaldehyde removing efficiency.

For the formaldehyde catalytic decomposition felt, the formaldehyde decomposition catalyst is extruded and dispersed in the pores among the materials forming the breathable support, so that the technical problem that the formaldehyde decomposition catalyst is difficult to uniformly distribute on the breathable support is well solved, and the formaldehyde removal effect of the formaldehyde catalytic decomposition felt is further improved.

When the formaldehyde catalytic decomposition felt is applied to the filter material with different functional layers, the formaldehyde decomposition catalyst in the formaldehyde catalytic decomposition felt can be effectively prevented from flowing and poisoning along with the substances to be filtered, so that the service life of the formaldehyde catalytic decomposition felt is prolonged.

The preparation method of the formaldehyde decomposition catalyst comprises the following steps of taking potassium permanganate, manganese sulfate and water as raw materials to carry out mixed reaction to obtain the formaldehyde decomposition catalyst, and specifically comprises the following steps:

A. preparing 60-110 g/L potassium permanganate solution from potassium permanganate and placing the potassium permanganate solution into a first titration tank, preparing 70-120 g/L manganese sulfate solution from manganese sulfate and placing the manganese sulfate into a second titration tank, wherein the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank is 3: 3-4: 3, and if the volume of the potassium permanganate solution in the first titration tank or the volume of the manganese sulfate solution in the second titration tank is set as a reference volume, the reference volume is not less than 50L;

B. respectively and simultaneously dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into bottom water which is pre-stored in a mixing reactor and has the volume more than 2 times of the reference volume, simultaneously and completely dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank within 10-45 min, and fully stirring the mixed solution at 70-90 ℃ until the reaction is finished;

C. and (3) carrying out solid-liquid separation on the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst.

A method for producing a formaldehyde decomposition catalyst, comprising subjecting a target to alkali washing to obtain an alkali-washed formaldehyde decomposition catalyst, wherein the target is: 1) potassium permanganate, manganese sulfate and water are taken as raw materials to be mixed and reacted to obtain a formaldehyde decomposition catalyst; 2) a precipitate obtained after step B in the above method for producing a formaldehyde decomposition catalyst; or 3) the formaldehyde decomposition catalyst obtained after step C in the above method for producing a formaldehyde decomposition catalyst.

The inventor finds that the formaldehyde decomposition catalyst prepared by taking potassium permanganate, manganese sulfate and water as raw materials has a possibly perceived peculiar smell, and can remove the peculiar smell of the formaldehyde decomposition catalyst through alkali washing, so that the use comfort of the formaldehyde decomposition catalyst is improved.

The manufacturing method of the formaldehyde catalytic decomposition felt comprises the following steps: providing a breathable support; providing a feed liquid containing a formaldehyde decomposition catalyst; extruding and dispersing the feed liquid on a breathable support, and drying the feed liquid to obtain the formaldehyde catalytic decomposition felt; wherein the formaldehyde decomposition catalyst is: 1) any one of the above formaldehyde decomposition catalysts; 2) a formaldehyde decomposition catalyst obtained by any one of the above-mentioned formaldehyde decomposition catalyst production methods; or 3) MnO of mainly delta crystal form₂The formed submicron-micron petal-shaped particles form the formaldehyde decomposition catalyst.

Further, the feed liquid is attached to the air-permeable support through a pulp drawing process, and the extrusion dispersion process exists in the pulp drawing process.

The invention is further described with reference to the following figures and detailed description. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to assist in understanding the invention, and are included to explain the invention and their equivalents and not limit it unduly. In the drawings:

FIG. 1 is a schematic view showing the structure of a filter material in example 1 of the present invention.

FIG. 2 is a schematic view showing the structure of a filter material in example 2 of the present invention.

FIG. 3 is a schematic structural view of a filter material according to example 3 of the present invention.

FIG. 4 is a schematic view showing the structure of a viscose layer of a filter material according to example 3 of the present invention.

Fig. 5 is a schematic structural view of a mold in the filter material production method of example 3 of the present invention.

FIG. 6 is a schematic view showing the structure of a filter material according to example 4 of the present invention.

FIG. 7 is a schematic view showing the structure of a filter material according to example 5 of the present invention.

FIG. 8 is a schematic view showing the structure of a filter material according to example 6 of the present invention.

FIG. 9 is a schematic view showing the structure of a filter material according to comparative example 1 of the present invention.

FIG. 10 is a schematic view showing the structure of a filter material in comparative example 2 of the present invention.

Fig. 11 is a schematic structural view of a filter material having a pleated structure according to the present invention.

Fig. 12 is a schematic view of an alignment adhesive filled and set between pairs of adjacent pleat waves of the filter material in accordance with the present invention.

Fig. 13 is a schematic view of the filter assembly of the present invention before the filter material is placed in the positioning frame.

FIG. 14 is a schematic view of the filter assembly of the present invention.

Fig. 15 is a schematic view of the filter of the present invention.

FIG. 16 is a scanning electron micrograph of a formaldehyde decomposition catalyst according to the invention of the present specification, wherein each of the images (a) to (d) is a photograph showing a selected field on a slide showing no tendency at microscopic observation.

Fig. 17 is an X-ray diffraction (XRD) pattern of the formaldehyde decomposition catalyst shown in fig. 16.

FIG. 18 is a scanning electron micrograph of a formaldehyde catalyzed decomposing felt according to the invention of the present specification, wherein each of the images (a) to (d) is a photograph showing a selected field of view on a slide showing no tendency at microscopic observation.

FIG. 19 is a scanning electron micrograph of a formaldehyde decomposition catalyst according to comparative example 1, wherein each of the images (a) to (b) is a photograph showing a selected field of view on a slide glass which is not apt to be observed microscopically.

FIG. 20 is a graph showing the change of formaldehyde concentration with time in the formaldehyde removal performance test using the formaldehyde decomposition catalyst of example A1.

FIG. 21 is a graph showing the change of formaldehyde concentration with time in the formaldehyde removing performance test using the formaldehyde decomposing catalyst of example A5.

FIG. 22 is a graph showing the change of formaldehyde concentration with time when a formaldehyde removing performance test was carried out using the formaldehyde decomposing catalyst of comparative example 1.

FIG. 23 is a scanning electron microscope image of a formaldehyde decomposition catalyst felt in the invention according to the present specification.

FIG. 24 is a graph showing the results of measuring the comprehensive properties of the formaldehyde decomposing mat of example B1-B5.

FIG. 25 is a graph showing the uniformity of distribution of the formaldehyde decomposition catalyst in the formaldehyde decomposition mats of example B2 and example B6.

Parts of the above figures are labelled:

120: a chemical filtration functional layer;

130: a protective functional layer;

111: a metal filter layer;

112: a fibrous filtration layer;

113: a second physical filter layer;

410: ultrasonic wave composite layer;

411: ultrasonic wave compound line;

412: a composite node;

510: a layer of glue filaments;

511: a glue thread unit;

512: glue silk;

610: and (6) overlapping strips.

Detailed Description

The invention will be described more fully hereinafter with reference to the accompanying drawings. Those skilled in the art will be able to implement the invention based on these teachings. Before the present invention is described in detail with reference to the accompanying drawings, it is to be noted that:

the technical solutions and features provided in the present invention in the respective sections including the following description may be combined with each other without conflict.

Moreover, the embodiments of the present invention described in the following description are generally only some embodiments of the present invention, and not all embodiments. Therefore, all other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort shall fall within the protection scope of the present invention.

With respect to terms and units in the present invention. The terms "comprising," "having," and any variations thereof in the description and claims of this invention and the related sections are intended to cover non-exclusive inclusions.

Example 1

As shown in fig. 1, the filter material of the present embodiment has different functional layers, and all the functional layers are composed of a chemical filter functional layer 120 and a protective functional layer 130, and the chemical filter functional layer 120 and the protective functional layer 130 are overlapped in the front-rear direction in the filter direction.

The protective function layer 130 has a porous structure and a pore size smaller than the particle size of the catalyst in the chemical filtration layer; the protective function layer 130 is a PP fiber felt, the aperture is 90 μm, and the thickness is 3 mm.

The chemical filtering function layer 120 is a chemical filtering layer for filtering at least one volatile organic compound; the chemical filter layer is a formaldehyde decomposition catalytic felt which comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; the thickness of the chemical filter layer is 3mm, and the air permeability is 3000m³/m²·h。

The chemical filtering functional layer 120 is connected with the protective functional layer 130 through a connecting layer, and the connecting layer is an ultrasonic composite layer. The ultrasonic composite layer is arranged at two positions and is symmetrically arranged by the central line of the filter material. Each ultrasonic composite layer 410 is composed of two parallel ultrasonic composite lines 411 with a distance of 3cm, and the ultrasonic composite lines 411 are composed of composite nodes 412 with a length of 3mm and a width of 1mm which are arranged at a distance of 2 mm.

Example 2

As shown in fig. 2, the filter material of the present embodiment has different functional layers, and all the functional layers are composed of a physical filter functional layer and a chemical filter functional layer 120, which are overlapped with each other in the front-rear direction of the chemical filter functional layer 120 in the filter direction.

The chemical filtering function layer 120 is a chemical filtering layer for filtering at least one volatile organic compound; the chemical filter layer is a formaldehyde decomposition catalytic felt which comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; the thickness of the chemical filter layer is 2mm, and the air permeability is 4560m³/m²·h。

The physical filtering functional layer is a first physical filtering layer for filtering solid particles in a substance to be filtered; the first physical filter layer is a metal filter layer 111, and the thickness of the metal filter layer 111 is 1.5mm, and the pore diameter is 80 μm.

The physical filtration function layer and the chemical filtration function layer 120 are connected through a connection layer, and the connection layer is an ultrasonic wave composite layer. The ultrasonic composite layer is arranged at three positions and is symmetrically arranged by the central line of the filter material. The ultrasonic composite layers 410 on the two sides are formed by intersecting a plurality of ultrasonic composite lines 411, the ultrasonic composite layer 410 in the middle is formed by 1 ultrasonic composite line 411, and the ultrasonic composite lines 411 are formed by arranging composite nodes 412 with the length of 3mm and the width of 1mm at intervals of 2 mm.

Example 3

As shown in fig. 3, the filter material of the present embodiment has different functional layers, and all the functional layers are composed of a physical filter functional layer and a chemical filter functional layer 120, which are overlapped with each other in the front-rear direction of the chemical filter functional layer 120 in the filter direction.

The chemical filtering function layer 120 is a chemical filtering layer for filtering at least one volatile organic compound; the chemical filter layer is a formaldehyde decomposition catalytic felt which comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; the thickness of the chemical filter layer is 1mm, air permeability of 5720m³/m²·h。

The physical filtering function layer is composed of a first physical filtering layer for filtering solid particles in a substance to be filtered and a second physical filtering layer 113 for filtering at least one volatile organic compound, and the first physical filtering layer and the second physical filtering layer 113 are overlapped front and back along the filtering direction. The first physical filter layer is a fiber filter layer 112, the fiber filter layer 112 is made of superfine PP fibers, and the thickness is 3 mm. The second physical filter layer 113 comprises activated carbon, and the particle size of the activated carbon is 0.01-0.1 mm.

The physical filtration function layer and the chemical filtration function layer 120 are connected through a connecting layer arranged between the first physical filtration layer and the chemical filtration layer, the connecting layer is a rubber silk layer 510, the thickness of the connecting layer is 0.5mm, and the second physical filtration layer 113 is filled in a gap between the first physical filtration layer and the chemical filtration layer, the gap is formed by the rubber silk layer 510, and the gap is 0.5 mm. The glue silk layer 510 is formed by arranging glue silk 512 with the diameter of 0.05 mm. The colloid silk layers 510 are arranged at four positions and respectively arranged at the edge of the contact surface of the first physical filtering layer and the chemical filtering layer to be filled with activated carbon powder as much as possible, and the width of each colloid silk layer 510 is 5 cm. As shown in fig. 4, each of the glue silk layers 510 includes a plurality of glue silk units 511 from top to bottom, the deposition directions of two adjacent glue silk units 511 are different, and each glue silk unit 511 includes a plurality of glue silks 512 arranged at an interval of 5 mm.

The preparation method of the filter material comprises the following steps:

(1) adopting a mold shown in fig. 5, placing the mold on the surface of the chemical filtering functional layer 120, then scattering activated carbon in through holes of the mold, and scraping and compacting to form a second physical filtering layer 113;

(2) and taking down the mold, spraying hot melt adhesive filaments on the positions, which are not scattered with the activated carbon, on the surface of the chemical filtering functional layer 120, and then bonding the first physical filtering layer with the chemical filtering functional layer 120 to obtain the filtering material.

Example 4

As shown in fig. 6, the filter material of the present embodiment has different functional layers, and all the functional layers are composed of a physical filter functional layer, a chemical filter functional layer 120, and a protective functional layer 130, which are overlapped front and back in the filter direction.

The protective function layer 130 has a porous structure and a pore size smaller than the particle size of the catalyst in the chemical filtration layer; the protective functional layer 130 is electrostatic cotton, the aperture is 90 μm, and the thickness is 1 mm.

The chemical filtering function layer 120 is a chemical filtering layer for filtering at least one volatile organic compound; the chemical filter layer is a formaldehyde decomposition catalytic felt which comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; the thickness of the chemical filtering layer is 0.5mm, and the air permeability is 6830m³/m²·h。

The physical filtering functional layer is composed of a first physical filtering layer for filtering solid particles in a substance to be filtered. The first physical filter layer is formed by a metal filter layer 111 and a fiber filter layer 112 which are overlapped front and back along the filter direction, the thickness of the metal filter layer 111 is 0.8mm, the pore diameter is 60 mu m, and the fiber filter layer 112 is made of superfine PP fibers and has the thickness of 0.8 mm.

An ultrasonic composite layer 410 is provided between the protective functional layer 130 and the chemical filter functional layer 120, and the setting parameters of the ultrasonic composite layer 410 are the same as those of embodiment 1 or embodiment 2. And the glue silk layers 510 are arranged between the chemical filtering functional layer 120 and the fiber filtering layer 112 and between the fiber filtering layer 112 and the metal filtering layer 111, the glue silk layers 510 in the butt joint surfaces of each layer are arranged at two positions and are symmetrically arranged by the central line of the filtering material, and the thickness of each glue silk layer 510 is 50 micrometers, and the width is 6 cm. The glue silk layer 510 is formed by arranging glue silk 512 with the diameter of 0.05 mm. As shown in fig. 4, each of the glue silk layers 510 includes a plurality of glue silk units 511 from top to bottom, the deposition directions of two adjacent glue silk units 511 are different, and each glue silk unit 511 includes a plurality of glue silk 512 arranged at an interval of 10 mm.

Example 5

As shown in fig. 7, the filter material of the present embodiment has different functional layers, and all the functional layers are composed of a physical filter functional layer, a chemical filter functional layer 120, and a protective functional layer 130, which are overlapped back and forth in the filter direction.

The chemical filtering function layer 120 is a chemical filtering layer for filtering at least one volatile organic compound; the chemical filter layer is a formaldehyde decomposition catalytic felt which comprises an air-permeable support and a formaldehyde decomposition catalyst attached to the air-permeable support; the thickness of the chemical filter layer is 0.1mm, and the air permeability is 8000m³/m²·h。

The physical filtering function layer is composed of a first physical filtering layer for filtering solid particles in a substance to be filtered and a second physical filtering layer 113 for filtering at least one volatile organic compound, and the first physical filtering layer and the second physical filtering layer 113 are overlapped front and back along the filtering direction. The first physical filter layer is composed of a metal filter layer 111 and a fiber filter layer 112 which are overlapped front and back along the filter direction, the thickness of the metal filter layer 111 is 0.12mm, the pore diameter is 40 mu m, and the fiber filter layer 112 is composed of superfine PP fibers and has the thickness of 0.18 mm. The second physical filter layer 113 comprises activated carbon, and the particle size of the activated carbon is 0.01-0.1 mm.

The protective function layer 130 has a porous structure and a pore size smaller than the particle size of the catalyst in the chemical filtration layer; the protective function layer 130 is a PET fiber felt, the aperture is 90 μm, and the thickness is 0.1 mm.

An ultrasonic composite layer 410 is provided between the protective functional layer 130 and the chemical filter functional layer 120, and the setting parameters of the ultrasonic composite layer 410 are the same as those of embodiment 1 or embodiment 2. A glue thread layer 510 is provided between the fiber filtration layer 112 and the metal filtration layer 111, and the setting parameters of the glue thread layer 510 are the same as those of example 4. A glue thread layer 510 is provided between the fiber filtration layer 112 and the chemical filtration function layer 120, and the setting parameters of the glue thread layer 510 are the same as those of embodiment 3.

The preparation method of the filter material comprises the following steps:

(1) the protective functional layer 130 and the chemical filtering functional layer 120 are connected in a composite mode through ultrasonic waves;

(2) adopting a mold shown in fig. 5, placing the mold on the surface of the chemical filtering functional layer 120, then scattering activated carbon in through holes of the mold, and scraping and compacting to form a second physical filtering layer 113;

(3) taking down the mold, spraying hot melt adhesive filaments on the positions of the surface of the chemical filtering functional layer 120 where the activated carbon is not scattered, then adhering the fiber filtering layer 112 with the chemical filtering functional layer 120,

(4) and connecting the fiber filter layer 112 with the metal filter layer 111 through glue spraying to obtain the filter material.

Example 6

Compared to example 5, the filter material of this example has the following differences: as shown in fig. 8, a lap strip is provided between the fiber filter layer 112 and the chemical filter function layer 120, and both upper and lower surfaces of the lap strip are respectively connected with the fiber filter layer 112 and the chemical filter function layer 120 by ultrasonic wave compounding.

The preparation method of the filter material comprises the following steps:

(2) the periphery of the chemical filtering functional layer 120 is connected with lap strips through ultrasonic waves in a compounding manner, the lap strips surround an arrangement space of activated carbon, then the activated carbon is scattered in the arrangement space, and a second physical filtering layer 113 is formed after the activated carbon is scraped and compacted;

(3) the fibrous filtration layer 112 is then ultrasonically composite bonded to the landing strip,

Comparative example 1 (comparative example of example 1)

Compared to example 1, the filter material of this example has the following differences: as shown in fig. 9, the ultrasonic composite lines 411 are uniformly distributed on the entire contact surface between the chemical filtration functional layer 120 and the protective functional layer 130.

Comparative example 2 (comparative example of example 1)

Compared to example 1, the filter material of this example has the following differences: as shown in fig. 10, the rubber thread layer 510 is uniformly distributed on the whole contact surface of the chemical filtration functional layer 120 and the protective functional layer 130, the rubber thread layer 510 is composed of an upper rubber thread unit 511 and a lower rubber thread unit 511, each rubber thread unit 511 is composed of rubber threads 512 arranged at a distance of 10mm, and the diameter of each rubber thread 512 is 0.05 mm.

It was confirmed that example 1 has a higher air permeability than comparative examples 1-2.

A filter assembly using the filter material 100 according to any one of embodiments 1 to 6, wherein the filter material 100 is used as the filter portion 210, and may be used while being folded or not. As shown in fig. 11-12, the folded filter material 100 has a pleated structure 101, one pair of opposite sides of the filter material 100 is a pleated wave-shaped side 101a, and the other pair of opposite sides is a straight side 101b, and at this time, the structure of the filter assembly is as shown in fig. 13-14, and includes a filter portion 210, a positioning portion 220 and a sealing portion 230, which are as follows:

the positioning part 220 includes a positioning frame 221 provided at the periphery of the filter material 100 to define the filter material 100 therein and open both sides of the filter material 100 to the outside, a conductive member 223 for electrically conductive connection with the metal filter layer in the filter material 100, and a pleat-conforming member 222 provided at the side of the filter material 100. The wrinkle shape-preserving member 222 includes supports spaced between a plurality of pairs of adjacent wrinkle waves 101c of the filter material 100, the supports are composed of positioning glue 222a respectively filled between the plurality of pairs of adjacent wrinkle waves 101c and solidified, and the positioning glue 222a is only filled between peaks corresponding to the adjacent wrinkle waves 101c and has a filling depth of 0.8 cm. The conductive member 223 includes a contact 223a (the contact position may be located on the side of the positioning frame 221, and the side of the contact 223a just contacts with the electrical connection terminal of the parent device such as the filter after the filter assembly 200 is installed on the parent device such as the filter) on the positioning portion 220, and a copper lug 223b for connecting with the metal filter layer on the positioning portion 220. The positioning frame 221 is a rectangular positioning frame matched with the filter material 100, and the positioning frame 221 includes: a side positioning frame 221a in which a sealing material is provided between the side positioning frame 221a and the filter material 100; an upper positioning frame 221b disposed at an upper end of the side positioning frame 221a and extending along a top edge of the side positioning frame 221 a; and a lower positioning frame 221c provided at a lower end of the side positioning frame 221a and extending along a bottom side of the side positioning frame 221 a. The upper positioning frame 221b is connected to the side positioning frame 221a in a split manner, the bottom surface of the upper positioning frame 221b is provided with a step surface 221b1 adapted to the upper end of the side positioning frame 221a, and a sealant located between the upper positioning frame 221b and the side positioning frame 221a is substantially filled in two parallel planes on the step surface 221b 1.

The sealing portion 230 includes a sealing material disposed between the filter material 100 and the positioning portion 220 to prevent the object to be filtered from penetrating through the inner boundary area of the positioning frame without passing through the filter material 100. The sealing material includes a sealant adhered between the linear side 101b of the filter material 100 and the positioning frame 221, and a sealing plate 231 located between the corrugated side 101a of the filter material 100 and the positioning frame 221. The surface of the filter material 100 on which the linear side 101b is located is directly bonded to the inner side surface of the corresponding positioning frame 221 by a sealant. The inner side surface of the sealing plate 231 is bonded to the surface of the corresponding filter material 100 on which the corrugated edge 101a is located, and the outer side surface is bonded to the inner side surface of the corresponding positioning frame 221 by a sealant.

A filter using the filter material 100 according to any one of embodiments 1 to 6 is shown in fig. 15, and includes an air inlet 310, an air outlet 320, and an air duct located between the air inlet 310 and the air outlet 320, the filter assembly 200 is mounted on the air duct, and the windward side of the filter assembly 200 is communicated with the air inlet 310 and the air outlet side is communicated with the air outlet 320. Since the thickness of the filter assembly 200 is thin due to the special structure of the filter material 100, the filter assembly 200 can be directly installed in an existing household air conditioner. In addition, the filter 300 may be operated with or without the metal filter layer of the filter assembly 200 being selectively charged.

In the following examples, examples of formaldehyde decomposition catalysts are given by "example A1", "example A2", "example A3", and the like (and so on). Examples of formaldehyde decomposition catalyst mats are indicated by "example B1", "example B2", "example B3", and the like (and so on).

Example A1

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 95g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 70g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 4:3, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume to be 50L, and calculating the volume of the manganese sulfate solution in the second titration tank to be approximately equal to 50L according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively and simultaneously dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into 100L of bottom water which is stored in a mixing reactor in advance, setting the titration time to be 10min (namely finishing dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank simultaneously in a time period of 10 min), and then fully stirring the mixed solution at 80 ℃ for 2 h; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then the obtained formaldehyde decomposition catalyst is cleaned, dried and dispersed.

FIG. 16 is a scanning electron micrograph of the formaldehyde decomposition catalyst of example A1, and FIGS. (a) to (d) in FIG. 16 are photographs showing the selected field of view on a slide glass showing no tendency at microscopic observation, respectively. Fig. 17 is an X-ray diffraction (XRD) pattern of the formaldehyde decomposition catalyst shown in fig. 16.

As shown in fig. 16, the formaldehyde decomposition catalyst of example a1 consisted primarily of submicron-micron petal shaped particles. Wherein, the diameter (i.e. the particle diameter) of the micron-scale petal-shaped particles is mainly distributed between 1 and 3 mu m, and the diameter of the submicron-scale petal-shaped particles is mainly distributed between 0.1 and 1 mu m.

Further observation shows that the submicron-micron petal-shaped particles are often in an agglomerated state, and because the diameters of the particles are not uniformly distributed, a large number of submicron-micron petal-shaped particles are irregularly distributed around the micron petal-shaped particles, so that the specific surface area of the agglomerated submicron-micron petal-shaped particles is increased.

As shown in FIG. 17, by combining the standard diffraction peaks of the (001), (002) and (111) crystal planes of delta-form manganese dioxide (JCPDS 80-1089), and by the literature "controllable preparation conditions of manganese dioxide of different crystal forms research, Wanggang, etc., inorganic salt industry, 8.2017", it can be confirmed that the submicron-micron petal-shaped particles of the formaldehyde decomposition catalyst of example A1 are MnO of delta crystal form₂。

Example A2

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 60g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 70g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 1, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume to be 50L, and calculating the volume of the manganese sulfate solution in the second titration tank according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into bottom water with the volume of 100L, which is stored in a mixing reactor in advance, at the same time, setting the titration time to be 10min, and then fully stirring the mixed solution for 2h at the temperature of 80 ℃; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then the obtained formaldehyde decomposition catalyst is cleaned, dried and dispersed.

Scanning electron microscopy of the formaldehyde decomposition catalyst of example a2 confirmed that the formaldehyde decomposition catalyst of example a2 conformed to the characteristics of being composed primarily of submicron-micron petal-like particles having a particular diameter distribution similar to the formaldehyde decomposition catalyst of example a 1.

X-ray diffraction testing of the formaldehyde decomposition catalyst of example A2 identified the formaldehyde decomposition catalyst of example A2MnO with delta crystal form of submicron-micron petal-shaped particles₂。

Example A3

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 110g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 120g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 1.1, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume to be 50L, and calculating the volume of the manganese sulfate solution in the second titration tank according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into bottom water with the volume of 100L, which is stored in a mixing reactor in advance, at the same time, setting the titration time to be 10min, and then fully stirring the mixed solution for 2h at the temperature of 80 ℃; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then the obtained formaldehyde decomposition catalyst is cleaned, dried and dispersed.

Scanning electron microscopy of the formaldehyde decomposition catalyst of example A3 confirmed that the formaldehyde decomposition catalyst of example A3 conformed to the characteristics of being composed primarily of submicron-micron petal-like particles having a particular diameter distribution similar to the formaldehyde decomposition catalyst of example a 1.

X-ray diffraction testing of the formaldehyde decomposition catalyst of example A3 confirmed that the submicron-micron petal particles of the formaldehyde decomposition catalyst of example A2 were MnO in the delta crystalline form₂。

Example A4

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 95g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 70g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 4:3, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume as 100L, and calculating the volume of the manganese sulfate solution in the second titration tank to be approximately equal to 100L according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into 200L of bottom water prestored in the mixing reactor at the same time, setting the titration time to be 18min, and fully stirring the mixed solution at 80 ℃ for 2 h; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then the obtained formaldehyde decomposition catalyst is cleaned, dried and dispersed.

Scanning electron microscopy of the formaldehyde decomposition catalyst of example a4 confirmed that the formaldehyde decomposition catalyst of example a4 conformed to the characteristics of being composed primarily of submicron-micron petal-shaped particles, which had an increased non-uniformity in diameter distribution over the formaldehyde decomposition catalyst of example a 1.

X-ray diffraction testing of the formaldehyde decomposition catalyst of example A4 confirmed that the submicron-micron petal particles of the formaldehyde decomposition catalyst of example A2 were MnO in the delta crystalline form₂。

Example A5

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 95g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 70g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 4:3, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume to be 300L, and calculating the volume of the manganese sulfate solution in the second titration tank to be approximately equal to 300L according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into 600L of bottom water which is stored in a mixing reactor in advance, setting the titration time to be 35min, and fully stirring the mixed solution for 2h at 80 ℃; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then the obtained formaldehyde decomposition catalyst is cleaned, dried and dispersed.

FIG. 18 is a scanning electron micrograph of the formaldehyde decomposition catalyst of example A5, and FIGS. (a) to (d) in FIG. 18 are photographs showing the selected field of view on a slide glass showing no tendency at microscopic observation, respectively. As shown in fig. 18, the formaldehyde decomposition catalyst of example a5 consisted primarily of submicron-micron petal shaped particles. Wherein, the diameter of the micron-scale petal-shaped particles is mainly distributed between 1 and 4 mu m, and the diameter of the submicron-scale petal-shaped particles is mainly distributed between 0.3 and 1 mu m.

Further observation shows that the submicron-micron petal-shaped particles tend to be in an agglomerated state, and due to the uneven diameter distribution of the particles, a large number of submicron petal-shaped particles are irregularly distributed around the micron petal-shaped particles (this phenomenon is more obvious than that of the formaldehyde decomposition catalyst in example a 1), so that the specific surface area of the agglomerated submicron-micron petal-shaped particles is larger. X-ray diffraction testing of the formaldehyde decomposition catalyst of example A5 confirmed that the submicron-micron petal particles of the formaldehyde decomposition catalyst of example A5 were MnO in the delta crystalline form₂。

Speculation of delta crystalline MnO₂The nonuniformity of the particle diameter distribution is related to the volume of the raw material potassium permanganate solution or manganese sulfate solution and the corresponding titration time, and it is further presumed that when the volume of the raw material potassium permanganate solution or manganese sulfate solution is large and the corresponding titration time is long, the grains that are the primary nuclei grow.

Example A6

The formaldehyde decomposition catalyst is obtained by taking potassium permanganate, manganese sulfate and water as raw materials through mixed reaction, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration of 95g/L, placing the potassium permanganate solution into a first titration tank, preparing manganese sulfate into a manganese sulfate solution with the concentration of 70g/L, placing the manganese sulfate solution into a second titration tank, setting the mass ratio of potassium permanganate in the first titration tank to manganese sulfate in the second titration tank to be 4:3, setting the volume of the potassium permanganate solution in the first titration tank as a reference volume, setting the reference volume to be 50L, and calculating the volume of the manganese sulfate solution in the second titration tank to be approximately equal to 50L according to the conditions and by combining the molecular weight of potassium permanganate and manganese sulfate; then respectively dripping the potassium permanganate solution in the first titration tank and the manganese sulfate solution in the second titration tank into bottom water with the volume of 100L, which is stored in a mixing reactor in advance, at the same time, setting the titration time to be 10min, and then fully stirring the mixed solution for 2h at the temperature of 80 ℃; then centrifugally dewatering the mixed solution after the reaction is finished to obtain a formaldehyde decomposition catalyst; and finally, centrifugally dewatering the mixed solution after the reaction is finished to obtain the formaldehyde decomposition catalyst. And then carrying out alkali washing, cleaning, drying and dispersing on the obtained formaldehyde decomposition catalyst.

The alkali washing refers to washing the formaldehyde decomposition catalyst by using alkali liquor. The embodiment specifically comprises the steps of adding the formaldehyde decomposition catalyst into deionized water, then adding a certain amount of alkali liquor to adjust the pH value of the solution to 9-11, and finally performing centrifugal dehydration to obtain the formaldehyde decomposition catalyst.

Comparative example 1

The formaldehyde decomposition catalyst is obtained by mixing and reacting potassium permanganate and absolute ethyl alcohol as raw materials, and specifically comprises the following steps: preparing potassium permanganate into a potassium permanganate solution with the concentration (mass percentage) of 1.25%, mixing and stirring 4L of the potassium permanganate solution and 1L of absolute ethyl alcohol, reacting at normal temperature for 10 hours, centrifugally dewatering the mixed solution after the reaction is finished to obtain a formaldehyde decomposition catalyst, and cleaning, drying and dispersing the obtained formaldehyde decomposition catalyst.

FIG. 19 is a scanning electron micrograph of the formaldehyde decomposition catalyst of comparative example 1, and FIGS. (a) to (b) in FIG. 19 are photographs showing selected fields of view on a slide glass which are not apt to be observed microscopically. As shown in FIG. 19, the formaldehyde decomposition catalyst of comparative example 1 was mainly formed by agglomeration of nano-sized particles. X-ray diffraction test of the formaldehyde decomposition catalyst of comparative example 1 confirmed that the formaldehyde decomposition catalyst of comparative example 1 was MnO of delta crystal form₂。

The formaldehyde removal performance test was conducted using the formaldehyde decomposition catalysts of example a1, example a5, and comparative example 1, respectively. The test principle and the method are as follows: the method comprises the steps of manufacturing a closed experiment chamber, wherein the size of the experiment chamber is 550mm multiplied by 415mm multiplied by 315mm, the experiment chamber is provided with a formaldehyde injection port and a formaldehyde concentration test instrument, the two sides of the experiment chamber are respectively provided with an air outlet and an air inlet, the air outlet and the air inlet are connected through a pipeline with the diameter of 200mm, the pipeline is provided with a fan, and in addition, the pipeline is also provided with a group of flanges for loading and unloading formaldehyde decomposition catalysts for test.

Before testing, a certain amount of formaldehyde decomposition catalyst is uniformly laid on a piece of PP breathable film, wherein the laying amount is 0.04g/cm²Then, another PP breathable film is used for covering the formaldehyde decomposition catalyst, and the two PP breathable films which are wrapped and clamped with the formaldehyde decomposition catalyst are clamped between the flanges, so that the formaldehyde decomposition catalyst is fixed in the pipeline.

During testing, firstly, the formaldehyde solution with certain volume and concentration is heated and injected into the experiment cabin through the formaldehyde injection port, so that the initial concentration of formaldehyde in the experiment cabin is 1.4-2.0 mg/m³And when the concentration of the formaldehyde in the experimental cabin is increased to the maximum value and stabilized for 1min, starting a fan and starting timing, recording the concentration of the formaldehyde in the experimental cabin every 5min, setting the testing time to be 15min, and keeping the power of the fan to be constant (the wind speed is about 3 m/s). After 15min, formaldehyde was again injected as described above and the test repeated for 15 min. The test was repeated 4 times for each formaldehyde decomposition catalyst.

The graphs of the change with time of the formaldehyde concentration in the experimental chamber obtained by the above formaldehyde removal performance test using the formaldehyde decomposition catalysts of example a1, example a5 and comparative example 1 are respectively shown in fig. 20, fig. 21 and fig. 22.

From the calculations shown in fig. 20, 21 and 22: the formaldehyde removing efficiency 10min before the above formaldehyde removing performance test procedure was carried out using the formaldehyde decomposition catalyst of example A1 was 76.2%, the formaldehyde removing efficiency 10min before the above formaldehyde removing performance test procedure was carried out using the formaldehyde decomposition catalyst of example A5 was 81.2%, and the formaldehyde removing efficiency 10min before the above formaldehyde removing performance test procedure was carried out using the formaldehyde decomposition catalyst of comparative example 1 was 64%.

The formaldehyde removing efficiency of the formaldehyde decomposition catalysts of example a1 and example a5 was better than that of the formaldehyde decomposition catalyst of comparative example 1, presumably due to: although the formaldehyde decomposition catalyst of the comparative example is composed of nano-sized particles, they are easily agglomerated, and particularly when they are adhered to an air-permeable support, these fine particles are agglomerated in a lump, which is disadvantageous in terms of sufficient contact with formaldehyde in the air; the formaldehyde decomposition catalyst of the embodiment has the advantages that due to the fact that the diameter distribution of the particles is not uniform, a large number of submicron petal-shaped particles are irregularly distributed around the micron petal-shaped particles, and the submicron-micron petal-shaped particles are enabled to be in full contact with formaldehyde in air after being agglomerated.

In addition, the odor test by a number of testers (test samples placed 15cm under the testers' nose) showed that the formaldehyde decomposition catalyst of example a6 had a significantly reduced odor compared to the formaldehyde decomposition catalysts of examples a1-a 5.

The formaldehyde decomposition catalyst related to the invention creation in the specification of the application can be directly used as a product to conduct the actions of manufacturing, selling, using and the like on the product, and can also be applied to the formaldehyde catalytic decomposition felt to conduct the actions of manufacturing, selling, using and the like on the formaldehyde catalytic decomposition felt. FIG. 23 is a scanning electron microscope image of a formaldehyde decomposition catalyst felt in the invention according to the present specification. As shown in fig. 23, the formaldehyde decomposition catalyst felt of interest in the invention creation referred to in the present specification includes an air-permeable support 121a and a formaldehyde decomposition catalyst (belonging to the decomposition catalyst 121b) attached to the air-permeable support.

As shown in fig. 23, the formaldehyde decomposition catalyst is distributed outside the material constituting the air-permeable support 121a and is mainly filled in the pores between the materials constituting the air-permeable support.

In addition, the formaldehyde decomposition catalyst generally further includes a binder distributed on the formaldehyde decomposition catalyst so as to be relatively firmly attached to the air-permeable support 121 a. The adhesive is preferably an acrylic adhesive or a polyurethane adhesive, and these adhesives do not adversely affect the use performance of the formaldehyde decomposition catalyst.

If the weight of the formaldehyde decomposition catalyst is divided by the weight of the gas-permeable support 121aThe windward area is set as the relative adhesion amount of the formaldehyde decomposition catalyst to the air-permeable support 121a, and the relative adhesion amount is generally 40g/m based on the formaldehyde removal efficiency of the formaldehyde decomposition catalyst according to the invention of the present specification²The formaldehyde decomposition catalyst felt basically has commercially acceptable formaldehyde removal effect.

Since the formaldehyde decomposition catalyst is adhered to the air-permeable support 121a, particularly when the relative adhesion amount is 40g/m²In order to make the formaldehyde decomposition catalyst felt have both a good formaldehyde removal effect and reasonable air permeability, it is suggested that the air permeable support 121a has an air permeability of not less than 3000m at a pressure difference of 100Pa³/m²H air-permeable fiber mats.

Since the filter material according to the invention of the present specification comprises different functional layers and the formaldehyde decomposition catalyst felt is used as only one of the functional layers, the air-permeable support 121a preferably has an air permeability of 5500m or more at a pressure difference of 100Pa to ensure air permeability of the entire filter material³/m²H air-permeable fiber mats.

The above-mentioned "air permeability at 100Pa pressure difference" may be in terms of the unit "m³/m²H "is understood. Specifically, "air permeability at a pressure difference of 100 Pa" means: cubic meters of air passing over the formaldehyde decomposition catalyst felt per unit square meter area per hour at a pressure differential of 100 pa.

Airfelt fibers having a permeability meeting the above-mentioned requirements can be obtained from the prior art, such as PP fiber felt, PET fiber felt, and the like. The PP fiber felt and the PET fiber felt not only have good air permeability, but also have proper performances such as strength and the like.

The formaldehyde catalytic decomposition felt in the invention and creation related to the present specification can be used not only as one of the functional layers of the filter material, but also in other application modes, and at this time, the shape, performance and other aspects of the air-permeable support 121a in the formaldehyde catalytic decomposition felt can be greatly changed.

In a place where formaldehyde concentration is high (e.g., furniture factory, paint factory, etc.), for better formaldehyde removal, a foam-like porous support may be used as the air-permeable support 121a in the formaldehyde catalytic decomposition mat so as to attach more formaldehyde decomposition catalyst. In order to independently install the formaldehyde catalytic decomposition felt on a specific passage, the air-permeable support 121a may be a support net, and the support net may be a woven net, a punched net, a diagonal net, or the like.

Example B1

The formaldehyde decomposition catalyst of example a1 was mixed with a dispersant and a binder to prepare a feed solution, wherein the binder was acrylic acid and the dispersant was water. The air-permeable support 121a is made of PP fiber felt. And attaching the feed liquid to the PP fiber felt through a pulp pulling process. When slurry is pulled, a belt material formed by the PP fiber felt is immersed into the feed liquid under the driving of the conveying roller, then vertically rises from the surface of the feed liquid, and then passes through a channel formed between a pair of scrapers positioned above the feed liquid, each scraper in the pair of scrapers moves in parallel along the surface of the corresponding PP fiber felt, so that extrusion force vertical to the surface of the PP fiber felt is applied to the formaldehyde decomposition catalyst, the formaldehyde decomposition catalyst attached to the PP fiber felt is extruded and dispersed in pores among materials forming the breathable support, and finally the formaldehyde catalytic decomposition felt is dried to obtain the formaldehyde catalytic decomposition felt. After drying, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is detected to be about 40g/m²。

Example B2

On the basis of the embodiment B1, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is increased, and the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is detected to be about 60g/m after drying²。

Example B3

On the basis of the embodiment B1, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is increased, and the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is about 80g/m after being dried²。

Example B4

On the basis of the example B1, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is increasedAfter drying, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is detected to be about 100g/m²。

Example B5

On the basis of the embodiment B1, the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is increased, and the relative adhesion amount of the formaldehyde decomposition catalyst on the PP fiber felt is detected to be about 120g/m after drying²。

Example B6

On the basis of the embodiment B2, an extrusion process is added between the pulp drawing process and the drying step. The pressing process comprises a pair of pressing rollers, a channel is formed between the pair of pressing rollers, and each pressing roller of the pair of pressing rollers rolls along the surface of the corresponding formaldehyde catalytic decomposition felt in parallel, so that the formaldehyde decomposition catalyst attached to the PP fiber felt is further pressed and dispersed in pores between materials forming the air-permeable support.

The formaldehyde removal performance tests were conducted using the formaldehyde catalytic decomposition mats of examples B1-B5, respectively, and the test principles and methods were substantially identical to those of the formaldehyde removal performance tests on formaldehyde decomposition catalysts, except that the formaldehyde catalytic decomposition mats were directly clamped between the flanges without the use of PP breathable films.

FIG. 24 is a graph showing the results of measuring the comprehensive properties of the formaldehyde decomposing mat of example B1-B5. In FIG. 24, the abscissa shows the relative adhesion of the formaldehyde decomposition catalyst to the PP fiber mat, wherein "40" means an adhesion of about 40g/m²The catalytic decomposition of the felt with formaldehyde corresponds to example B1, and so on. The left ordinate of FIG. 24 shows the air flow rate in m³/m²H means the cubic meter value of air passing per unit square meter area of formaldehyde decomposition catalyst mat per hour, with larger values indicating better permeability of the formaldehyde decomposition catalyst mat and conversely worse. The left ordinate of FIG. 24 is the formaldehyde removal rate, which can be calculated from the same data as shown in FIGS. 20-22.

As shown in FIG. 24, the formaldehyde removing efficiency in the 10min before the formaldehyde removing performance test using the formaldehyde decomposition mat of example B1-B5 gradually increased from about 66% to 72%, although the increase was slight.

The formaldehyde decomposition catalyst mats of examples B1-B5 were each used to conduct an air permeability test that measures the cubic meter value of air passing over the formaldehyde decomposition catalyst mat per unit square meter area per hour at a pressure differential (specifically 10 Pa). Due to flow meter reading limitations, when permeability tests were conducted using the formaldehyde decomposition mats of examples B1-B5, each of the tests on a formaldehyde decomposition mat was conducted by stacking 6 sheets of the same formaldehyde decomposition mat together, which allowed the flow rate to be reduced to meet the flow meter reading limitations.

As shown in FIG. 24, the formaldehyde decomposition mats of examples B1-B5 had successively lower air permeabilities when the relative adhesion amounts were 70g/m²About (60 g/m)²～70g/m²And (b) the air permeability and formaldehyde removal efficiency of the formaldehyde catalytic decomposition felt are comprehensively optimal.

Although it is shown in FIG. 24 that the relative adhesion amount is 120g/m²The air permeability of the formaldehyde catalytic decomposition felt is 0, but the phenomenon cannot indicate that the formaldehyde catalytic decomposition felt is not air-permeable because 6 pieces of the same formaldehyde catalytic decomposition felt are overlapped when in test, and each piece of formaldehyde catalytic decomposition felt has certain air permeability actually.

FIG. 25 is a graph showing the uniformity of distribution of the formaldehyde decomposition catalyst in the formaldehyde decomposition mats of example B2 and example B6. The comparison chart is that two formaldehyde catalytic decomposition felts are put together for light transmission observation, and the observation clearly shows that the formaldehyde decomposition catalyst distribution of the formaldehyde catalytic decomposition felt of the embodiment B6 is obviously more uniform and finer.

Examples 1 to 6 and comparative examples 1 to 2 were carried out using the formaldehyde decomposition catalyst and the production method thereof as provided in example A1.

Examples 1 to 6 and comparative examples 1 to 2 were filter materials in which the formaldehyde decomposition catalyst felt provided in example B2 was used.

The contents of the present invention have been explained above. Those skilled in the art will be able to implement the invention based on these teachings. All other embodiments, which can be derived by a person skilled in the art from the above description without inventive step, shall fall within the scope of protection of the present invention.

Claims

1. The preparation method of the filter material comprises a physical filter function layer and a chemical filter function layer (120) which are overlapped in a front-back mode along a filter direction, wherein the physical filter function layer comprises a first physical filter layer and a second physical filter layer (113), the first physical filter layer and the second physical filter layer are overlapped in the front-back mode along the filter direction, solid particles in a substance to be filtered are filtered, the second physical filter layer (113) filters at least one volatile organic compound, and the second physical filter layer (113) comprises activated carbon; the preparation method of the filter material comprises the following steps:

(1) scattering activated carbon powder on the surface of the chemical filtering functional layer (120) or the first physical filtering layer to form a second physical filtering layer (113);

(2) and forming a connecting layer which connects the first physical filtering layer and the chemical filtering functional layer (120) and is positioned at the periphery of the second physical filtering layer (113) by glue spraying and/or ultrasonic wave compounding to obtain the filtering material.

2. A method of making a filter material as claimed in claim 1, wherein: the particle size of the activated carbon powder is 0.01-5 mm, preferably 0.03-1 mm, and more preferably 0.05-0.3 mm.

3. A method of making a filter material as claimed in claim 1, wherein: also comprises the steps of scraping and compacting the active carbon powder accumulation layer.

4. A method of making a filter material as claimed in claim 1, wherein: the first physical filtration layer is a fibrous filtration layer (112) or a metal filtration layer (111); or the first physical filter layer is composed of a metal filter layer (111) and a fiber filter layer (112) which are overlapped back and forth along the filtering direction, and a connecting layer formed by glue spraying and/or ultrasonic wave compounding is arranged between the metal filter layer (111) and the fiber filter layer (112).

5. A method of making a filter material as claimed in claim 1, wherein: all the functional layers comprise a protective functional layer (130), the chemical filtering functional layer (120) and the protective functional layer (130) are overlapped front and back along the filtering direction, a connecting layer formed by glue spraying and/or ultrasonic wave compounding is arranged between the chemical filtering functional layer (120) and the protective functional layer (130), and the protective functional layer (130) has a porous structure and the aperture is smaller than the particle size of a catalyst in the chemical filtering functional layer (120).

6. A method of making a filter material as claimed in claim 1, wherein: the device also comprises an overlapping strip with the thickness matched with that of the second physical filtering layer (113), the overlapping strip is positioned between the first physical filtering layer and the chemical filtering functional layer (120) and encloses a placing space of the activated carbon powder, and the upper surface and the lower surface of the overlapping strip are respectively in composite connection with the first physical filtering layer and the chemical filtering functional layer (120) through glue spraying and/or ultrasonic waves; preferably, the overlapping strip has a porous structure.

7. A method of making a filter material as claimed in claim 1, wherein: also includes using a mold for preventing the activated carbon powder from falling into the connection layer, the mold having through holes matched with the size of the second physical filter layer (113).

8. A method of manufacturing a filter material as claimed in any one of claims 1 to 7, wherein: the connecting layers of each butt joint surface are distributed symmetrically.

9. A method of manufacturing a filter material as claimed in any one of claims 1 to 7, wherein: the connecting layer formed by glue spraying is a glue silk layer (510), the glue silk layer (510) comprises a plurality of glue silk units (511) distributed from top to bottom, and the deposition directions of two adjacent glue silk units (511) are different; the glue silk unit (511) is formed by arranging glue silk (512) with the diameter less than or equal to 0.1mm at a certain interval; the width of the rubber silk layer (510) is 3-6 cm.

10. A method of manufacturing a filter material as claimed in any one of claims 1 to 7, wherein: the connecting layer formed by ultrasonic wave compounding is an ultrasonic wave compounding layer (410), the ultrasonic wave compounding layer (410) is composed of one or more ultrasonic wave compounding lines (411), and the ultrasonic wave compounding lines (411) are composed of compounding nodes (412) with the length being less than or equal to 3mm and the width being less than or equal to 1mm in an arrangement mode according to the interval of 1-3 mm.