JPH0663101U - Liquid phase adsorption filter - Google Patents

Abstract

(57) [Summary] [Purpose] A liquid phase that has the advantages of fibrous activated carbon and powdered or granular activated carbon, eliminates the disadvantages, can adsorb a wide range of substances, and has excellent adsorption and filtration performance. Provide an adsorption filter. [Structure] A sheet 1 containing fibrous activated carbon and a sheet 2 made by mixing powdered or granular activated carbon with organic or inorganic fibers and a binder are stacked and rolled up into a cylindrical shape to form a filter body 3, A liquid phase adsorption filter in which the side surface on the outlet side of the treatment liquid is covered with an auxiliary filter 4 composed of a fiber layer.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a liquid phase adsorption filter capable of adsorbing a wide range of substances and having excellent adsorption performance and filtration performance.

[0002]

[Prior art]

 Activated carbon is used in the form of powder, granules, fibres, etc., each with its own characteristics. Powdered and granular activated carbon can adsorb comparatively high molecular weight substances due to the surface pore characteristics, and since the packing density is high, the adsorption amount per unit volume is large. However, there is no fixed form and the packing density is high, so the pressure loss is large. In addition, it has the disadvantages of poor handling and processability, and some of the activated carbon easily flows out or falls off.

On the other hand, fibrous activated carbon has a fast adsorption rate and is excellent in adsorption to a substance having a relatively low molecular weight. In addition, it is easy to handle and work, and the pressure loss is not so large. However, due to the surface pore characteristics, the adsorption of high molecular weight compounds is poor. In addition, since the packing density is low, there is the drawback that the adsorption amount per unit volume is small.

In order to eliminate the above-mentioned drawbacks when using fibrous activated carbon, powder and granular activated carbon alone, Japanese Utility Model Laid-Open No. 63-94527 discloses a fibrous activated carbon sheet and a sheet-like support. An adsorption filter for an air cleaner has been proposed in which activated carbon supported on the body is arranged in layers and the outer periphery is covered with a breathable sheet.

[0005]

[Problems to be solved by the device]

 The filter described in Japanese Utility Model Laid-Open No. 63-94527 was suitable for gas phase adsorption treatment, but was not suitable for liquid phase treatment. In other words, when supporting activated carbon on a sheet-shaped support, activated carbon is only thinly supported on the surface of the sheet-shaped support and is unevenly distributed on the surface. For this reason, it was difficult to efficiently adsorb the molecules in the liquid by liquid-phase adsorption, which has a slower diffusion rate than in the gas phase. In addition, it is inevitable that the activated carbon will fall off and flow out into the liquid simply by supporting the activated carbon on the sheet-shaped support. If some of the activated carbon falls off, the activated carbon will be more unevenly distributed in the filter, and the adsorption performance will decrease. Furthermore, when activated carbon is loaded on the sheet-shaped support, there is a large variation in the amount of activated carbon in the sheet-shaped support, and as a result of the large amount of activated carbon falling off, there is a problem that there is a large variation in the performance between individual filters. there were.

The present invention solves the above problems and utilizes the advantages of each of the fibrous activated carbon and the powdered or granular activated carbon, while eliminating the disadvantages, capable of adsorbing a wide range of substances, and having excellent adsorption performance and filtration. The technical problem is to provide a liquid phase adsorption filter having high performance.

[0007]

[Means for Solving the Problems]

 The present inventors have arrived at the present invention as a result of extensive studies to solve these problems. That is, according to the present invention, a sheet containing fibrous activated carbon and a sheet made by mixing powdered or granular activated carbon with organic or inorganic fibers and a binder are stacked and rolled up in a cylindrical shape to form a filter body. The gist is a liquid-phase adsorption filter, which is formed by covering the side surface on the outlet side of the treatment liquid with an auxiliary filter composed of a fiber layer.

Hereinafter, the present invention will be described in detail.

The liquid phase adsorption filter of the present invention, as shown in FIG. 2, is a sheet made by mixing a sheet 1 containing fibrous activated carbon, powdered or granular activated carbon, organic or inorganic fibers and a binder. 2 is piled up and rolled up into a cylindrical shape to form a filter body 3, and at least the side surface on the outlet side of the processing liquid is covered with an auxiliary filter 4 composed of a fiber layer. The example of FIG. 1 is a filter. This shows an example in which both sides of the main body 3 are covered with auxiliary filters 4.

When the sheets 1 and 2 are rolled up into a cylindrical shape and formed, the positional relationship between the sheets 1 and 2 is not particularly limited, but if the sheet 2 is on the inlet side of the liquid to be treated, it may be powdery. Even if the granular activated carbon falls off from the sheet 2, it can be collected by the sheet 1 and the powder or granular activated carbon can be prevented from flowing out into the treatment liquid. Alternatively, one or more sheets 1 and 2 may be formed by stacking different numbers.

In the present invention, it is necessary to cover at least the side surface on the outlet side of the processing liquid of the filter main body with an auxiliary filter composed of a fiber layer, but normally, from the outer peripheral side to the inner peripheral side in order to reduce resistance. Since the liquid to be treated often flows to the inside, it is generally installed on the inner peripheral side.

The raw material of the fibrous activated carbon contained in the sheet 1 may be regenerated cellulose fiber, acrylic fiber, phenol fiber, coal pitch or the like. Further, in order to impart good adsorption performance, the specific surface area of the fibrous activated carbon is preferably 300 m ² / g or more, particularly 500 to 2500 m ² / g.

The powder or granular activated carbon contained in the sheet 2 may be coconut shell, coal, wood powder, or the like, but a specific surface area of 300 m ² / g or more, particularly 500 to give good adsorption performance. It is preferably about 1500 m ² / g. In order to compensate for the lack of adsorption capacity for relatively high molecular weight substances, which is a deficiency of fibrous activated carbon, the volume of pores with a pore size of 20Å or more is 15% or more of the total pore volume, and the particle size is 0.5 mm. The following are 90% or more and are preferable.

[0014] In order to obtain a liquid phase adsorption filter which has good workability at the time of winding and has excellent filtration performance and a small pressure loss, it is preferable that the basis weight of the sheets 1 and 2 is 20 to 800 g / m ^2. The sheet 1 preferably has a bulk density of 0.01 to 0.2 g / cm ³ , and the sheet 2 preferably has a bulk density of 0.02 to 0.5 g / cm ³ . The content of the fibrous activated carbon or the powdered or granular activated carbon in the sheets 1 and 2 is preferably 5% by weight or more in order to impart excellent adsorption ability.

Other materials contained in the sheet 1 include organic and inorganic substances such as natural fibers, synthetic fibers, pulp, glass fibers, ceramic fibers, etc., and one or more of them may be used at the same time. Good. In order to improve the moldability, it is particularly preferable to blend a heat-fusible material such as synthetic fiber, and as the synthetic fiber, polyester, copolyester, polyolefin, polyamide, etc. are preferably used. Further, the sheet 2 may contain powder or granular activated carbon and other materials such as pulp in addition to organic or inorganic fibers and binder.

The sheet 1 is manufactured by a method of supplying fibrous activated carbon and other materials to a card machine and performing opening and mixing to form a web, or by mixing fibrous activated carbon and other materials, There are methods such as wet papermaking.

The sheet 2 is obtained by mixing powdered or granular activated carbon, organic or inorganic fibers and a binder such as polyvinyl alcohol, and making a paper from this slurry. The amount of the binder blended is 10% by weight of the sheet 2. % Or less is preferable. The sheet 2 may be formed by mixing both organic fibers and inorganic fibers.

The material of the auxiliary filter 4 that covers at least the side surface of the filter body 3 that is the outlet side of the treatment liquid is not particularly limited, but a woven or non-woven fabric having good workability and heat-sealing property is preferable. . Further, the auxiliary filter 4 has excellent filtering performance and is preferably breathable to some extent, and the basis weight is preferably 10 to 100 g / m ² .

The liquid phase adsorption filter of the present invention can be obtained by simply stacking a sheet containing fibrous activated carbon and a sheet made by mixing powdered or granular activated carbon with organic or inorganic fibers and a binder. Since fibrous activated carbon can be combined with powdered or granular activated carbon, it requires less labor and cost compared to other methods, and is extremely compact.

In addition, if a sheet containing fibrous activated carbon and several types of sheets made by mixing powdered or granular activated carbon with organic or inorganic fibers and a binder are prepared, various combinations can be prepared. You can easily make a filter. Furthermore, the ratio of fibrous activated carbon and powdered or granular activated carbon can be easily changed by adjusting the number of layers.

[0021]

[Action]

 In the liquid phase adsorption filter of the present invention, powder or granular activated carbon is mixed with organic or organic fiber and binder to form a paper-made sheet into a cylindrical shape. It can be evenly dispersed and fixed. In addition, the powdered or granular activated carbon is present in the interstices inside the organic or inorganic fibers that are overlapped and entangled with each other, and the movement of the organic or inorganic fibers is suppressed, so they fall off and flow into the liquid. hard. Furthermore, if a sheet containing fibrous activated carbon is mixed with powdered or granular activated carbon, organic or inorganic fibers and a binder and formed into multiple layers to form a sheet, a filter with a large filtration volume is obtained. However, it is possible to further enhance the filtration performance with an auxiliary filter provided on the side that is the outlet side of the treatment liquid, and to prevent the powder or granular activated carbon from flowing out into the liquid even if it falls off from the filter body. .

Further, the fibrous activated carbon and powder or granular activated carbon having different adsorption properties can adsorb a wide range of substances from low molecular weight to high molecular weight. In this case, the efficient adsorption capacity of the fibrous activated carbon with a high adsorption rate and the powder or granular activated carbon with a high packing density are used to supplement the adsorption amount per unit volume, thereby exhibiting a sufficient adsorption capacity within the specified volume. can do. Moreover, the pressure loss does not increase, and part of activated carbon does not flow out or fall off.

[0023]

【Example】

 Next, the present invention will be specifically described with reference to examples.

Example 1 As fibrous activated carbon, a material prepared from coal pitch and cut into 5 mm was prepared. The specific surface area of this fibrous activated carbon was measured by the low temperature nitrogen adsorption method using the "Autosorb 6" automatic gas adsorption measuring device manufactured by Kantachrome Co., and was 1000 m ² / g. Also, the pore volume was examined by the same method. As a result, the total pore volume was 0.52 cm ³ / g, of which 2% had a pore size of 20 Å or more.

Sheet 1 was obtained by a wet method using a slurry obtained by mixing 70% by weight of the above fibrous activated carbon and 30% by weight of a polyethylene synthetic pulp having an average fiber length of 1.3 mm. The obtained sheet 1 had a basis weight of 80 g / m ² and a bulk density of 0.11 g / cm ³ .

Further, as powdered activated carbon, coconut shell was used as a raw material, and 100% mesh pass, that is, particle size of 0.149 mm or less was prepared at 94.5%. The specific surface area of this powdered activated carbon measured by the same method as the fibrous activated carbon was 912 m ² / g, the total pore volume was 0.66 cm ³ / g, and 42% of them had a pore diameter of 20 Å or more.

Sheet 2 was obtained by a wet method using a slurry prepared by mixing 62% by weight of the above powdered activated carbon, 30% of hemp and 7% by weight of polyvinyl alcohol. The sheet 2 thus obtained had a basis weight of 60 g / m ² and a bulk density of 0.3 g / cm ³ .

The sheet 1 and the sheet 2 obtained above are stacked so that the sheet 2 is on the outside, and the sheet is preliminarily wound around an iron core wrapped with a non-woven fabric to form a cylindrical object, and the non-woven fabric is further formed on the cylindrical product. After winding, it was heat treated to form a cylindrical shape. The obtained liquid-phase adsorption filter had an outer diameter of 60 mm and an inner diameter of 30 mm, with the inner and outer layers of the cylindrical filter body covered with an auxiliary filter made of non-woven fabric. The non-woven fabric used above was composed of a composite fiber having polyethylene terephthalate as a core and polyethylene as a sheath, and had a basis weight of 30 g / m ² . Table 1 shows the results of adsorption tests conducted using the obtained liquid phase adsorption filter having a length of 250 mm.

Further, as Comparative Example 1, a filter was manufactured in the same manner as in Example 1 except that the filter body was formed only from the sheet 1 obtained above. Further, as Comparative Example 2, coconut shell-based granular activated carbon having a specific surface area of 1000 m ² / g and 30 to 60 mesh was filled so as to have the same size as that of the filter of Example 1, and the outside and the inside were covered with a nonwoven fabric. . Table 1 shows the results of the adsorption test conducted using the filters obtained in Comparative Examples 1 and 2.

[0030]

[Table 1]

In Table 1, the activated carbon filling amount indicates the total content of fibrous activated carbon and powder or activated carbon. In addition, the pressure loss indicates the pressure loss after passing water at 5 liter / min for 10 minutes. Next, in the adsorption test, Fast Red A having a molecular weight of 400 and Vitamin B ₁₂ having a molecular weight of 1357 were adjusted to 100 mg / liter with ion-exchanged water and passed at 1 liter / min for 10 minutes. After that, those with no coloration at the outlet were evaluated as ◯, and those with coloration were evaluated as x. Furthermore, the outflow of activated carbon was confirmed by filtering the water sampled at the outlet with a membrane filter with a pore size of 0.45 μm immediately after passing water at 5 liters / min. All of the above tests were carried out by passing the water to be treated from the outer peripheral side to the inner peripheral side of the filter.

As is clear from Table 1, in the case of the filter obtained in Example 1, activated carbon did not flow out, and both Fast Red A and vitamin B ₁₂ could be adsorbed well. Also, the activated carbon filling amount could be increased as compared with Comparative Example 1. Furthermore, in order to examine the filtration performance, a 10 ppm iron hydroxide aqueous solution was flown at a flow rate of 4 liters / min, and the number of particles in the solution before and after filtration was measured by a Coulter counter. .

On the other hand, in Comparative Example 1, there is no problem with pressure loss, adsorption of Fast Red A, and outflow of activated carbon, but the ability to adsorb vitamin B ₁₂ having a large molecular weight is inferior and the amount of activated carbon packed is small. It was In Comparative Example 2, although the activated carbon filling amount was large, the activated carbon was observed to flow out, and since it was granular activated carbon, the adsorption rate was slow, and the adsorption capacity could not be fully exhibited under the above liquid passing conditions. It was

[0034]

[Effect of device]

 According to the present invention, a wide range of substances can be adsorbed, the advantages of each of fibrous activated carbon and powdered or granular activated carbon can be utilized, the disadvantages can be eliminated, and a wide range of substances can be adsorbed, resulting in excellent adsorption performance. It is possible to provide a liquid-phase adsorption filter that has filtration performance and is suitable for liquid-phase treatment in various fields such as water purification, plating bath purification, and brewing liquor purification.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a liquid phase adsorption filter of the present invention.

FIG. 2 is a perspective view showing a state in which sheets 1 and 2 are stacked and rolled up into a cylindrical shape.

[Explanation of symbols]

 1 sheet 1 2 sheet 2 3 filter body 4 auxiliary filter

Claims (1)

[Scope of utility model registration request] 1. A filter main body is formed by stacking a sheet containing fibrous activated carbon and a sheet made by mixing powdered or granular activated carbon, organic or inorganic fibers and a binder and making a paper, to form a filter body. A liquid-phase adsorption filter characterized in that the side surface on the outlet side of the liquid is covered with an auxiliary filter composed of a fiber layer.