KR20160113437A - Coating apparatus of membrane on porous support layer and coating method using the same - Google Patents

Abstract

Disclosed are a method to coat a porous support body, and an apparatus thereof. More particularly, the method to coat a porous support body sprays a coating solution comprising a powder for coating to a porous support body by applying a pressure to the coating solution, and allows the powder for coating to be coated in a filtering way. Thus, a film is coated on a porous support body, and the coating layer has enhanced adhesive strength and density. Also, the method to coat a porous support body can manufacture a uniform coating layer which does not generate defects on a large-sized porous support body having a complicated shape.

Description

TECHNICAL FIELD [0001] The present invention relates to a porous support coating apparatus and a coating method thereof,

The present invention relates to a porous support coating apparatus and a coating method thereof, and more particularly, to a porous support coating apparatus and a coating method thereof by spraying onto a porous support by applying a pressure to a coating solution containing a coating powder, A porous support coating device capable of improving the adhesion and compactness of a coating layer coated on a porous support and capable of producing a coating layer which is uniform and does not generate defects even for a porous support having a large area having a complicated shape, ≪ / RTI >

Porous ceramics have been actively studied in various fields because of their unique characteristics such as low density, low thermal conductivity and low dielectric constant. In particular, ceramic separators are one of the most feasible applications among porous ceramics.

These porous ceramics membranes have various industrial application fields such as purification of foodstuffs and medicines, filtration of waste gas, and representative examples thereof are used as separators for water purification. Although polymer membranes are widely used industrially, they have a disadvantage in that they have low mechanical strength, low chemical stability, and low temperature resistance.

On the other hand, porous ceramics membranes are superior to polymer membranes in terms of acid resistance and high-temperature stability, and can be used for separating and purifying solutions containing strong acids, strong alkalis, organic solvents, and oils under conditions more severe than polymer membranes And can be used at high temperatures. In addition, the porous ceramic separator has an advantage of being superior in biological resistance and durability compared with a polymer membrane.

In the case of such a porous ceramic separator, a coating layer is formed by coating a liquid coating sol on one surface or both surfaces of the porous support with a dip coating type.

However, when a coating layer is formed on one surface or both surfaces of a porous support by a dip coating method in order to manufacture a porous ceramic separator, the density of the coating powder is low and the shrinkage ratio during drying and sintering is increased. Which causes defects such as cracks.

A related prior art is Korean Patent Laid-Open Publication No. 10-2005-0071352 (published on July 7, 2005), which discloses a ceramic filter having a support and a method of manufacturing the same.

It is an object of the present invention to provide a method of coating a porous support by applying a pressure to a coating solution containing a powder for coating so as to coat the powder particles for coating in a filtering manner to improve the adhesion and compactness of the coating layer coated on the porous support The present invention also provides a porous support coating apparatus and coating method which can produce a coating layer that is homogeneous and does not generate defects even for a large area porous support having a complicated shape. At this time, the pressure to be added to the solution is the hydraulic pressure when the medium is water, and the hydraulic pressure which is generally the pressure of the fluid.

In order to accomplish the above object, according to a first aspect of the present invention, there is provided a coating apparatus for coating a porous support having a plurality of channels passing through the inside thereof and a coating powder for coating a porous support having self- A coating solution storage tank; A support holder for fixing both side edges of the porous support; A coating chamber mounted to surround the porous support and the support holder, the coating chamber providing a coating space for coating the outer surface of the porous support; A coating solution supply pipe for supplying a coating solution stored in the coating solution storage tank to the interior of the coating chamber, the coating solution supply pipe being connected to the coating solution storage tank and the coating chamber; A pump for pumping a coating solution containing coating powder stored in the coating solution storage tank into the coating chamber, the coating solution being supplied to the coating solution supply pipe; A water pressure controller for controlling an intensity of a water pressure by controlling a frequency applied to the pump; And an aqueous solution discharge pipe connected to the support holder and extending to the outside of the coating chamber, for discharging the remaining aqueous solution coated inside the coating chamber.

In order to accomplish the above object, according to a second aspect of the present invention, there is provided a coating apparatus for coating a porous support having a plurality of channels passing through the inside thereof and a porous support having a self- A coating solution storage tank; A support holder for fixing both side edges of the porous support; A coating chamber mounted to enclose the porous support and the support holder, the coating chamber providing a coating space for coating the plurality of channel inner walls of the porous support; A coating solution supply pipe for supplying a coating solution stored in the coating solution storage tank to a plurality of channel inner walls of the porous support, the coating solution supply pipe being installed in a pulsating circulation structure for connecting the coating solution storage tank and the support holder, ; A pump for pumping the coating solution stored in the coating solution storage tank to the interior of the coating chamber; A water pressure controller for controlling an intensity of a water pressure by controlling a frequency applied to the pump; And an aqueous solution discharge pipe installed at one side of the coating chamber for discharging the remaining aqueous solution coated inside the coating chamber.

According to a first aspect of the present invention, there is provided a porous support coating method comprising: (a) providing a porous support having a plurality of channels and self-pores penetrating the support, Charging; (b) forming a coating layer on the outer surface of the porous support by a filtering method using water pressure so that a coating solution containing powder for coating is sprayed into the coating chamber; And (c) taking out the porous support having the coating layer formed thereon to the outside of the coating chamber, followed by drying and sintering.

According to a second aspect of the present invention, there is provided a porous support coating method comprising the steps of: (a) providing a porous support having a plurality of channels and self-pores penetrating the support, Charging; (b) forming a coating layer by coating a plurality of channel inner walls of the porous support by a filtering method using water pressure so that a coating solution containing powder for coating is sprayed into the coating chamber; And (c) taking out the porous support having the coating layer formed thereon to the outside of the coating chamber, followed by drying and sintering.

The porous support coating apparatus and coating method thereof according to the present invention can be applied to a porous support by applying a pressure to a coating solution containing a coating powder so that the coating powder particles are coated in a filtering manner, Since the coating can be performed at a uniform density, the coated layer can be formed by overcoming the shrinkage ratio during drying and sintering, thereby improving the adhesion and denseness of the laminated powder.

Since the porous support coating apparatus and coating method according to the present invention can selectively coat the outer surface of the porous support or the plurality of channel inner walls of the porous support manufactured by extrusion molding to a complicated shape, Structure, and even if the porous support has a complicated shape, it is possible to densely and uniformly coat the outer surface of the porous support or the inner wall of the plurality of channels by the pulling force from the plurality of pores .

The porous support coating apparatus and coating method according to the present invention may include a plurality of porous supports having any one of tubular, flat tubular and monolithic structures and a structure in which a plurality of support holders are connected in parallel to the coating solution supply pipe , It is possible to coat a plurality of porous supports at one time, so that the cost and time for coating can be remarkably reduced.

1 is a view showing a porous support coating apparatus according to a first embodiment of the present invention.
2 is a schematic view for explaining a porous support before and after coating using the porous support coating apparatus of FIG.
3 is a view showing a porous support coating apparatus according to a second embodiment of the present invention.
FIG. 4 is a schematic view for explaining a porous support before and after coating using the porous support coating apparatus of FIG. 3. FIG.
5 is a view showing a porous support coating apparatus according to a modification of the second embodiment of the present invention.
6 is an enlarged view of a portion of a porous support coating apparatus according to another modification of the second embodiment of the present invention.
7 is a process flow diagram illustrating a porous support coating method according to a first embodiment of the present invention.
8 is a schematic view of a process for explaining a coating process using a hydraulic pressure of a fluid.
9 is a photograph showing a surface of a coating layer of the specimen according to Example 1 taken by SEM.
10 is a photograph showing a cut surface of a specimen according to Example 1, taken by SEM.
11 is a photograph showing a cut surface of a specimen according to Comparative Example 1 taken by SEM.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a porous support coating apparatus and a coating method thereof according to preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view showing a porous support coating apparatus according to a first embodiment of the present invention, and FIG. 2 is a schematic view for explaining a porous support before and after coating using the porous support coating apparatus of FIG.

1 and 2, a porous support coating apparatus 200 according to a first embodiment of the present invention includes a coating solution storage tank 210, a support holder 220, a coating chamber 230, a coating solution supply pipe A water pump 240, a pump 250, a water pressure controller 260 and an aqueous solution discharge pipe 270.

The coating solution storage tank 210 stores a coating solution 145 containing a coating powder for coating a plurality of channels 125 penetrating the inside and a porous support 120 having self-pores (not shown) It plays a role. 2 (a), the porous support 120 has a hollow channel 125 obtained by a method of extrusion or the like, and a porous pore held by the porous pore itself. The coating solution storage tank 210 may be mounted on one side of the porous support 120 spaced apart from the porous support 120. In particular, it is preferable to use a low-concentration slurry composed of dilute colloid particles as the coating solution 145 containing the coating powder. When the slurry having a high concentration is used as the coating solution 145, the density of the coating powder is low It is possible to cause a crack defect at the interface between the porous support 120 and the coating layer (140 in Fig. 2).

The support holder 220 is mounted for the purpose of fixing both side edges of the porous support 120. It is preferable that the support holder 220 is installed to seal the plurality of channels 125 of the porous support 120 by connecting the aqueous solution from which the coating powder in the coating solution has been removed to the support holder 220 To the outside of the coating chamber 230 through the aqueous solution discharge pipe 270.

The coating chamber 230 is mounted to enclose the porous support 120 and the support holder 220 and provides a coating space for coating the outer surface of the porous support 120. Such a coating chamber 230 may have a rectangular parallelepiped shape, but this is an exemplary one, and various shapes such as a dome structure and the like can be applied.

The coating solution supply pipe 240 is installed between the coating solution storage tank 210 and the coating chamber 230 to connect the coating solution 145 stored in the coating solution storage tank 210 to the coating chamber 230. [ (230). That is, one end of the coating solution supply pipe 240 communicates with the coating solution storage tank 210, and the other end of the coating solution supply pipe 240 communicates with the coating chamber 230.

The pump 250 is installed in the coating solution supply pipe 240 and serves to pump the coating solution 145 containing the coating powder stored in the coating solution storage tank 210 into the interior of the coating chamber 230 . The pump 250 is preferably mounted on the coating solution supply pipe 240 between the coating solution storage tank 210 and the water pressure controller 260, but is not limited thereto.

The water pressure controller 260 is mounted for the purpose of controlling the intensity of the water pressure by adjusting the frequency applied to the pump 250. The water pressure controller 260 controls the driving frequency of the pump 250 to control the pressure of the coating solution 145 supplied to the inside of the coating chamber 230 through the coating solution supply pipe 240 at a desired water pressure.

The aqueous solution discharge pipe 270 is connected to the support holder 220, respectively. At this time, the aqueous solution discharge pipe 270 extends to the outside of the coating chamber 230 and discharges the remaining aqueous solution coated inside the coating chamber 230. Accordingly, when a water-based coating is performed inside the coating chamber 230, the coating powder is coated on the outer surface of the porous support 120, as shown in FIG. 2 (b). At this time, the aqueous solution from which the coating powder is removed from the coating solution passes through the plurality of channels 125 of the porous support 120 and the support holder 220 and flows through the aqueous solution discharge pipe 270 to the outside of the coating chamber 230 .

At this time, it is preferable that the coating is performed by filtering while supplying the coating solution 145 at a constant pressure at the time of coating using the water pressure. If the pressure is too low, it is difficult to form a dense coating layer 140, and if the pressure is too high, the porous support 120 may be damaged and the coating layer 140 may be increased in thickness. Therefore, it is appropriate to apply 0.01 to 3 bar, more preferably 0.5 to 1.5 bar, at a constant pressure during coating.

Also, in this step, as the coating time increases, the thickness of the coating layer 140 becomes thick. However, since excessive coating time may cause an increase in pressure, it is appropriate to perform coating at an appropriate time.

The porous support coating apparatus according to the first embodiment of the present invention may be applied to the outer surface of the porous support by applying water pressure to the coating solution containing the coating powder so that the coating powder particles are coated by the filtering method The coating can be formed at uniform density in all directions. Since the denseness of the laminated powder is high due to the high adhesion and the high density, the coating layer can be formed by overcoming the shrinkage rate during drying and sintering have.

In addition, since the porous support coating apparatus according to the first embodiment of the present invention can selectively coat the outer surface of the porous support, which is formed into a complicated shape by extrusion molding, it is possible to provide an excellent effect And even if the porous support has a complicated shape, it is possible to perform a dense but uniform coating on the outer surface of the porous support by the pulling force from the plurality of pores.

FIG. 3 is a view showing a porous support coating apparatus according to a second embodiment of the present invention, and FIG. 4 is a schematic view illustrating a porous support before and after coating using the porous support coating apparatus of FIG.

3 and 4, the porous support coating apparatus 300 according to the second embodiment of the present invention includes a coating solution storage tank 310, a support holder 320, a coating chamber 330, A pump 340, a pump 350, a water pressure controller 360, and an aqueous solution discharge pipe 370.

The coating solution storage tank 310 stores a coating solution 145 containing a coating powder for coating a plurality of channels 125 penetrating the inside and a porous support 120 having self-pores (not shown) It plays a role. 4 (a), the porous support 120 has a hollow channel 125 obtained by a method of extrusion or the like, and a porous pore held by the porous pore itself. The coating solution storage tank 310 may be mounted on one side of the porous support 120 spaced apart from the porous support 120. In particular, it is preferable to use a low-concentration slurry composed of dilute colloid particles as the coating solution 145 containing the coating powder. When the slurry having a high concentration is used as the coating solution 145, the density of the coating powder is low This may cause a crack defect at the interface between the porous support 120 and the coating layer (140 in Fig. 4).

The support holder 320 serves to fix both side edges of the porous support 120. It is preferable that the support holder 320 is installed to seal the plurality of channels 125 of the porous support 120 so that the aqueous solution from which the powder for coating in the coating solution has been removed in the coating process is supplied to one side of the coating chamber 330 To the outside of the coating chamber 330 through the aqueous solution discharge pipe 370 mounted on the coating chamber 330.

The coating chamber 330 is mounted to enclose the porous support 120 and the support holder 320 and provides a coating space for coating the inner walls of the plurality of channels 125 of the porous support 120. Such a coating chamber 330 may have a rectangular parallelepiped shape, but this is an exemplary one, and various shapes such as a dome structure and the like can be applied.

The coating solution supply pipe 340 is installed in a pulsating circulation structure for connecting the coating solution storage tank 310 and the support holder 320 to each other so that the coating solution 145 stored in the coating solution storage tank 310 To the inner walls of the plurality of channels 125 of the porous support 120. When the coating solution supply pipe 340 is installed in a pulmonary circulation structure interconnected between the coating solution storage tank 310 and the supporter holder 320, the coating solution 145 containing the coating powder is continuously supplied A uniform coating can be induced with a structural advantage that can be made to circulate.

The pump 350 is mounted on the coating solution supply pipe 340 and is mounted for the purpose of pumping the coating solution 145 stored in the coating solution storage tank 310 into the interior of the coating chamber 330. The pump 350 is preferably mounted on the coating solution supply pipe 340 between the coating solution storage tank 310 and the water pressure controller 360, but is not limited thereto.

The water pressure controller 360 controls the intensity of the water pressure by adjusting the frequency applied to the pump 350. The water pressure controller 360 adjusts the driving frequency of the pump 350 to supply the water into the plurality of channels 125 of the porous support 120 through the coating solution supply pipe 340 and the support holder 320 at a desired water pressure. Thereby controlling the pressure of the coating solution 145.

The aqueous solution discharge pipe 370 is mounted on one side of the coating chamber 330 to discharge the coating solution remaining in the coating chamber 330. 4 (b), the coating powder is coated on the inner walls of the plurality of channels 125 of the porous support 120, do. At this time, the aqueous solution from which the coating powder is removed from the coating solution is discharged to the outside of the coating chamber 330 through the aqueous solution discharge pipe 370 mounted on one side of the coating chamber 330 through the self-pores of the porous support 120 do.

At this time, it is preferable that the coating is performed by filtering while supplying the coating solution 145 at a constant pressure at the time of coating using the water pressure. If the pressure is too low, it is difficult to form a dense coating layer 140, and if the pressure is too high, the porous support 120 may be damaged and the coating layer 140 may be increased in thickness. Therefore, it is appropriate to apply 0.01 to 3 bar, more preferably 0.5 to 1.5 bar, at a constant pressure during coating.

Also, in this step, as the coating time increases, the thickness of the coating layer 140 becomes thick. However, since excessive coating time may cause an increase in pressure, it is appropriate to perform coating at an appropriate time.

5 is a view showing a porous support coating apparatus according to a modification of the second embodiment of the present invention.

Referring to FIG. 5, a porous support coating apparatus 300 according to a modification of the second embodiment of the present invention includes a porous support coating apparatus 300 (FIG. 3) according to the second embodiment described with reference to FIGS. 3 and 4, As shown in Fig.

However, in the case of the porous support coating apparatus 300 according to the modification of the second embodiment of the present invention, the porous support 120 and the support holder 320 are arranged in parallel with each other, (Not shown).

In this way, when the plurality of support holders 320 are designed to be connected in parallel by the coating solution supply pipe 340, it is possible to coat the plurality of porous supports 120 at one time The cost and time for coating can be significantly reduced.

6 is an enlarged view of a portion of a porous support coating apparatus according to another modification of the second embodiment of the present invention.

6, the porous support coating apparatus 300 according to another modified example of the second embodiment of the present invention is a porous support coating apparatus 300 according to a modified example of the second embodiment shown and described with reference to FIG. 5 5 < / RTI > 300).

However, unlike the modification of the second embodiment, the porous support coating apparatus 300 according to the other modified example of the second embodiment of the present invention is different from the modification of the second embodiment in that a plurality of porous supports 120 and a plurality of filtering holders 320, And has the same monolith structure.

The porous support coating apparatus according to the second embodiment of the present invention may be applied to a plurality of channels of a porous support by applying water pressure to a coating solution containing a coating powder, , The coating can be performed at uniform density in all directions. As the density of the powder is high due to its high adhesion and excellent denseness, the coating layer overcomes the shrinkage during drying and sintering to form a coating layer with reduced defects can do.

In addition, since the porous support coating apparatus according to the second embodiment of the present invention can selectively coat a plurality of channel inner walls of a porous support formed into a complicated shape by extrusion molding, It is possible not only to have an excellent effect but also to make a dense and uniform coating on the inner walls of the plurality of channels of the porous support by the force pulling from the plurality of pores even if the porous support has a complicated shape.

Further, the porous support coating apparatus according to the second embodiment of the present invention has a structure in which a plurality of porous supports and a plurality of support holders are connected in parallel by a coating solution supply pipe, so that a plurality of porous supports It is possible to make coatings on the coating layer, and the cost and time for coating can be remarkably reduced.

Hereinafter, a porous support coating method according to embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 7 is a process flow chart showing a porous support coating method according to the first embodiment of the present invention, which will be described in connection with FIG.

Referring to FIGS. 1 and 7, the porous support coating method according to the first embodiment of the present invention includes a charging step S110, a coating step S120, and a drying and sintering step S130.

Charging

In the charging step S110, the plurality of channels 125 passing through the inside and the porous support 120 having the self-pores (not shown) are fixed to the support holder 220 and charged into the coating chamber 230 do.

At this time, the porous support 120 has a hollow channel 125 obtained by a method such as extrusion, and porous pores possessed by the porous support itself. Such a porous support 120 can be manufactured by forming a formed body having a plurality of channels by using a mixed powder including ceramic powder and a pore-forming agent, and then drying and sintering the formed body. Such a mixed powder may be prepared by uniformly mixing a ceramic powder and a pore forming agent by wet mixing, for example, by any one of ball milling, planetary milling and attrition milling. As shown in FIG.

The kind of the ceramic powder is not particularly limited as long as it is a known material used in the production of the ceramic separator. For example, ceramic powders include diatomaceous earth (Diatomite), aluminum nitride (AlN), silicon nitride (Si ₃ N _4), silicon carbide (SiC), zirconium carbide (ZrC), tungsten carbide (WC), alumina (Al ₂ O ₃ ), cordierite, mullite, zirconia (ZrO ₂ ) and the like can be used.

The pore-forming agent is not particularly limited as long as it is an organic pore-forming agent that is pyrolyzed and removed in the sintering process to form pores, and specific examples thereof include polyacrylonitrile, poly (methyl methacrylate) Starch, polystyrene, or the like may be used.

In addition, the porous support 120 may further include a strength enhancing agent. As the strength improver, at least one selected from sodium borate (Na ₂ B ₄ O ₇揃 10H ₂ O), calcium carbide (CaC ₂ ), BaO, SrO and CaO may be used.

coating

In the coating step S120, the outer surface of the porous support 120 is coated with a water-pressure filtering method to spray the coating solution 145 containing the powder for coating into the coating chamber 230 to form a coating layer 140 ).

In this case, conventionally, the porous support 120 is coated with a liquid coating solution by a dip coating method. However, in this case, since the density of the coating powder is low, the problem of causing defects such as cracks due to an increase in shrinkage ratio during drying and sintering .

In contrast, in the present invention, the outer surface of the porous support 120 is coated with a filtering method using a water pressure to improve the adhesiveness and denseness of the coating powder, thereby suppressing the occurrence of defects due to reduction in the shrinkage rate during drying or sintering .

That is, when the coating is performed by the filtering method using the water pressure, the coating powder is coated on the outer surface of the porous support 120. The aqueous solution from which the coating powder has been removed from the coating solution passes through the plurality of channels 125 of the porous support 120 and the support holder 220 and is then discharged through the aqueous solution discharge pipe 270 to the coating chamber 230, As shown in FIG.

FIG. 8 is a process diagram for explaining the coating process using the hydraulic pressure of the fluid, and will be described in more detail with reference to FIG.

As shown in FIG. 8, when the coating solution 145 containing the coating particles is coated with a fluid pressure or a water pressure, the pressure applied in the fluid uniformly acts on all portions Therefore, since the coating can be performed at uniform density in all directions, it is possible to provide a coating having high adhesiveness and high density, which is capable of coating, and a coating layer 140 in which defects are suppressed by overcoming the shrinkage ratio during drying and sintering .

When the porous support 120 is coated by a filtering method using a fluid pressure or a water pressure, the coating solution 145 covers the pores of the porous support 120 to be irrespective of the thickness of the coating layer 140 The maximum pore size can be determined. At this time, the coating solution 145 is preferably a low-concentration slurry made of dilute colloid particles.

In addition, as in the present invention, when the coating solution 145 is coated by a filtering method using a fluid pressure or a water pressure, the outer surface of the porous support 120, which is formed into a complex shape by extrusion molding, The porous support 120 can be coated with the porous support 120 so that it has an excellent effect in manufacturing the separation membrane of the multi-layered pore structure. In addition, even if the porous support 120 has a complicated shape, It may be possible to perform a dense and uniform coating on the substrate.

In particular, the compactness of the coating layer 140 is controlled by inducing a change in water pressure in accordance with the porosity and average pore size of the porous support 120.

At this time, it is preferable that the coating using the fluid pressure or the water pressure is performed by supplying the coating solution 145 at a constant pressure while filtering. If the pressure is too low, it is difficult to form a dense coating layer 140, and if the pressure is too high, the porous support 120 may be damaged and the coating layer 140 may be increased in thickness. Therefore, it is appropriate to apply 0.01 to 3 bar, more preferably 0.5 to 1.5 bar as the initial pressure at the time of coating.

Also, in this step, as the coating time increases, the thickness of the coating layer 140 becomes thick. However, since excessive coating time may cause an increase in pressure, it is appropriate to perform coating at an appropriate time.

Drying and sintering

1 and 7, in the drying and sintering step S130, the porous support 120 on which the coating layer 140 is formed is taken out of the coating chamber 230, followed by drying and sintering. At this time, any one of drying, room temperature drying, microwave drying, freeze drying, solvent drying, and flash drying may be used. The sintering may be carried out under any one of the conditions selected from an atmospheric pressure atmosphere, a vacuum atmosphere, a reducing atmosphere, an inert atmosphere, and the like.

Meanwhile, the porous support coating method according to the second embodiment of the present invention is substantially the same as the porous support coating method according to the first embodiment. Referring to FIGS. 3 and 7, the overlapping description will be omitted, do.

As shown in Figs. 3 and 7, in the case of the porous support coating method according to the second embodiment according to the second embodiment of the present invention, the method of the first embodiment is substantially the same as the method of the first embodiment except for the coating step S120 So duplicate description is omitted.

In the coating step S120, coating is performed on the inner walls of the plurality of channels 125 of the porous support 120 by using a hydraulic pressure filtering method so that the coating solution 140 containing the coating powder is sprayed into the coating chamber 330 The coating layer 140 is formed.

That is, when coating is performed by a filtering method using a water pressure, the coating powder is coated on the inner walls of the plurality of channels 125 of the porous support 120. At this time, the aqueous solution from which the coating powder is removed from the coating solution is discharged to the outside of the coating chamber 330 through the aqueous solution discharge pipe 370 mounted on one side of the coating chamber 330 through the self-pores of the porous support 120 do.

The porous support coating method according to the first and second embodiments of the present invention can coat the coating solution with a uniform density in all directions by coating the coating solution with a filtering method using water pressure, It is possible to form a coating layer in which defects are suppressed by overcoming the shrinkage ratio during drying and sintering.

In addition, since the porous support coating method according to the first and second embodiments of the present invention can selectively coat the outer surface or the plurality of channel inner walls of the porous support, which is formed into a complicated shape by extrusion molding The present invention is not only capable of achieving an excellent effect in the preparation of a membrane having a multilayer pore structure but also capable of performing dense and uniform coating on an outer surface of a porous support or a plurality of channel inner walls by a force pulling from a plurality of pores even if the porous support has a complicated shape It can be possible.

Therefore, the porous ceramic separation membrane manufactured by the porous support coating method according to the first or second embodiment of the present invention comprises a porous support having a plurality of pores, a porous support coated on the porous support and having pores smaller than the plurality of pores Coating layer. At this time, the pores of the coating layer have a size smaller than 1/3 of the average diameter of the pores of the porous support.

Example

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

1. Porous support coating

Example 1

20 g of Al ₂ O ₃ of 0.3 탆 in size, 0.06 g of Darvan-C as a dispersant, and 0.5 g of PVA as an organic binder were placed in a polypropylene container together with an alumina ball, followed by ball milling for 24 hours. 5 g of the slurry was diluted with 995 g of distilled water so that the slurry obtained by the ball milling was 0.05 wt% based on Al ₂ O ₃ to prepare a coating solution.

Next, the coating solution was coated into the interior of the coating chamber filled with the porous support by an initial pressure of 1.5 bar and a time of 20 sec to form a coating layer on the outer surface of the porous support.

Next, the porous support on which the coating layer was formed was taken out to the outside of the coating chamber, dried at 65 ° C for 20 hours, and then heated at a rate of 5 ° C / min in an air atmosphere and sintered at 1200 ° C for 90 minutes to form a porous ceramic separator .

Example 2

A porous ceramic membrane was prepared in the same manner as in Example 1, except that the coating was performed by a filtering method using water pressure under the conditions of an initial pressure of 1 bar and a time of 10 seconds.

Example 3

Except that the coating solution was applied to the inside of the coating chamber filled with the porous support by an initial pressure of 1 bar and a filtering method using water pressure for 30 seconds to form a coating layer on the inner walls of the plurality of channels of the porous support A porous ceramic membrane was prepared in the same manner as in Example 1.

Example 4

Except that the coating solution was applied to the inside of the coating chamber filled with the porous support by a filtering method using water pressure at an initial pressure of 0.5 bar and a time condition of 30 sec to form a coating layer on the inner walls of a plurality of channels of the porous support A porous ceramic membrane was prepared in the same manner as in Example 1.

Comparative Example 1

20 g of Al ₂ O ₃ of 0.3 탆 in size, 0.06 g of Darvan-C as a dispersant, and 0.5 g of PVA as an organic binder were placed in a polypropylene container together with an alumina ball, followed by ball milling for 24 hours. 10 g of the slurry was diluted with 990 g of distilled water so that the slurry obtained by the ball milling was 0.1 wt% based on Al ₂ O ₃ to prepare a coating solution.

Next, a coating solution was applied to the porous support by dip coating for 5 times to form a coating layer.

Next, the porous support on which the coating layer was formed was dried at 65 ° C for 20 hours, then heated at a rate of 5 ° C / min in an air atmosphere, and sintered at 1200 ° C for 90 minutes to prepare a porous ceramic separator.

2. Pore measurement evaluation

Table 1 shows the measurement results of the pore size of the coating layer and the thickness of the coating layer for the specimens according to Examples 1 to 4 and Comparative Example 1.

[Table 1]

Referring to Table 1, in the case of the specimens according to Examples 1 to 4, the pore size of the coating layer was measured to be 0.13 to 0.16 mu m.

On the other hand, in the case of the specimen according to Comparative Example 1, the pore size of the coating layer was measured to be 0.57 mu m, which is a considerably larger value than the specimens according to Examples 1 to 4. As a result, As a result, cracks occurred at the interface between the porous support and the coating layer.

In the case of the test pieces according to Examples 1 to 4 and Comparative Example 1, although the thickness of the coating layer slightly varied according to the pressure and the coating time, the thickness of the coating layer tended to increase with an increase in the coating time .

3. Microstructure Observation

6 is a photograph showing the surface of a coating layer of the specimen according to Example 1 taken by SEM, and FIG. 7 is a photograph showing a cut surface of the specimen according to Example 1, taken by SEM. 8 is a photograph of a cut surface of a specimen according to Comparative Example 1 taken by SEM.

As shown in Figs. 6 and 7, in the case of the specimen according to Example 1, the coating particles are densely formed by performing the coating by the filtration method using the hydraulic pressure of water, so that the coating particles pore the pores of the porous support You can see what is blocking.

At this time, it can be confirmed that the coating layer is densely laminated on the porous support, and the interface between the porous support and the coating layer exists smoothly without the presence of cracks.

On the other hand, as shown in FIG. 8, it can be seen that cracks occurred at the interface between the porous support and the coating layer in the case of the test piece according to the comparative example 1, which is attributed to the formation of a dense coating layer .

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. These changes and modifications may be made without departing from the scope of the present invention. Accordingly, the scope of the present invention should be determined by the following claims.

200, 300: Porous support coating apparatus 210, 310: Coating solution storage tank
220, 320: support holder 230, 330: coating chamber
240, 340: coating solution supply piping 250, 350: pump
260, 360: water pressure controller 260, 360: aqueous solution discharge pipe
120: porous support 125: channel
140: Coating layer 145: Coating solution
S110: charging step
S120: coating step
S130: drying and sintering step

Claims (14)

(a) providing a porous support having a plurality of channels therethrough and self-pores therein; And
(b) coating the coating solution containing the powder for coating on the porous support by a filtering method using fluid pressure to form a coating layer;
≪ / RTI >
The method according to claim 1,
The density of the coating layer
Wherein the porous support is controlled by causing a change in fluid pressure according to a porosity and an average pore size of the porous support.
The method according to claim 1,
After the step (b)
(c) drying and sintering the coating layer formed on the porous support.
The method according to claim 1,
The coating layer
Wherein the porous support is coated on the porous support and has pores smaller than the pores of the porous support.
5. The method of claim 4,
The pores of the coating layer
Wherein the average diameter of the porous support is 1/3 or less of the pore size of the porous support.
A coating solution storage tank for storing a coating solution containing a coating powder for coating a porous support having a plurality of channels and self-pores penetrating the inside thereof;
A support holder for fixing both side edges of the porous support;
A coating chamber mounted to surround the porous support and the support holder, the coating chamber providing a coating space for coating the outer surface of the porous support;
A coating solution supply pipe for supplying a coating solution stored in the coating solution storage tank to the interior of the coating chamber, the coating solution supply pipe being connected to the coating solution storage tank and the coating chamber;
A pump for pumping a coating solution containing coating powder stored in the coating solution storage tank into the coating chamber, the coating solution being supplied to the coating solution supply pipe;
A water pressure controller for controlling an intensity of a water pressure by controlling a frequency applied to the pump; And
And an aqueous solution discharge pipe connected to the support holder and extending to the outside of the coating chamber for discharging the remaining aqueous solution coated inside the coating chamber.
The method according to claim 6,
Upon coating with water pressure inside the coating chamber,
Wherein the coating powder is coated on the outer surface of the porous support and the aqueous solution from which the coating powder has been removed in the coating solution passes through the plurality of channels of the porous support and the support holder and flows through the aqueous solution discharge pipe Wherein the porous support is coated on the porous support.
A coating method using the porous support coating apparatus according to any one of claims 6 to 7,
(a) charging a porous support having a plurality of channels and self-pores through the interior of the coating chamber in a state of being fixed to a support holder;
(b) forming a coating layer on the outer surface of the porous support by a filtering method using water pressure so that a coating solution containing powder for coating is sprayed into the coating chamber; And
(c) transporting the porous support, on which the coating layer is formed, to the outside of the coating chamber, and then drying and sintering the porous support.
9. The method of claim 8,
In the step (b)
The coating powder
The aqueous solution coated on the outer surface of the porous support and the coating powder removed from the coating solution passes through the plurality of channels of the porous support and the support holder and is discharged to the outside of the coating chamber through the aqueous solution discharge pipe ≪ / RTI >
A coating solution storage tank for storing a coating solution containing a coating powder for coating a porous support having a plurality of channels and self-pores penetrating the inside thereof;
A support holder for fixing both side edges of the porous support;
A coating chamber mounted to enclose the porous support and the support holder, the coating chamber providing a coating space for coating the plurality of channel inner walls of the porous support;
A coating solution supply pipe for supplying a coating solution stored in the coating solution storage tank to a plurality of channel inner walls of the porous support, the coating solution supply pipe being installed in a pulsating circulation structure for connecting the coating solution storage tank and the support holder, ;
A pump for pumping the coating solution stored in the coating solution storage tank to the interior of the coating chamber;
A water pressure controller for controlling an intensity of a water pressure by controlling a frequency applied to the pump; And
And an aqueous solution discharge pipe installed at one side of the coating chamber for discharging the remaining aqueous solution coated inside the coating chamber.
11. The method of claim 10,
Upon coating with water pressure inside the coating chamber,
The coating powder is coated on the inner walls of the plurality of channels, and the aqueous solution from which the coating powder is removed from the coating solution passes through the self-pores of the porous support and is discharged to the outside of the coating chamber through the aqueous solution discharge pipe By weight.
11. The method of claim 10,
The porous support and the support holder
Wherein the coating solution supply pipe is connected to the coating solution supply pipe in a parallel structure in which a plurality of the coating solution supply pipes are spaced apart from each other in parallel.
A coating method using the porous support coating apparatus according to any one of claims 10 to 12,
(a) charging a porous support having a plurality of channels and self-pores through the interior of the coating chamber in a state of being fixed to a support holder;
(b) forming a coating layer by coating a plurality of channel inner walls of the porous support by a filtering method using water pressure so that a coating solution containing powder for coating is sprayed into the coating chamber; And
(c) transporting the porous support, on which the coating layer is formed, to the outside of the coating chamber, and then drying and sintering the porous support.
14. The method of claim 13,
In the step (b)
Wherein the coating powder is coated on the inner walls of a plurality of channels of the porous support, and the aqueous solution from which the coating powder is removed from the coating solution passes through the self-pores of the porous support to the outside of the coating chamber through the aqueous solution discharge pipe Wherein the porous support coating is discharged.

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