JP2018065136A - Filter, filtration system, and decaffeination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter excelling in decaffeination efficiency and work efficiency.SOLUTION: A filter has a filter matrix containing activated clay powder or acid clay powder with an average particle diameter of 0.1-100 μm in a range of 20-80 mass% on the basis of mass of the filter matrix, and ultrahigh molecular weight polyethylene powder or high molecular weight polyethylene powder in a range of 80-20 mass% on the basis of the mass of the filter matrix.SELECTED DRAWING: None

Description

  The present invention relates to a filter and a filtration system. The present invention also relates to a caffeine removal filter, a caffeine removal system, and a caffeine removal method.

  Coffee and tea contain caffeine. A method for removing caffeine from a beverage containing caffeine has been proposed. In Patent Document 1, a specific aqueous solution containing caffeine is brought into contact with activated clay or acidic clay having a pH of 2.5% to 3.5% suspension to selectively remove caffeine from the aqueous solution. A method of removing is disclosed. Patent Document 2 is characterized in that a caffeine-containing catechin composition is dissolved in a mixed solution having an organic solvent / water weight ratio of 9/1 to 1/9 and contacted with activated carbon and acidic clay or activated clay. And a method for selectively removing caffeine from a caffeine-containing catechin composition.

JP-A-6-142405 JP 2004-222719 A

  In the method of adding active clay powder to a liquid containing caffeine and stirring, it is necessary to perform solid-liquid separation by filtration after the clay treatment, and workability tends to be complicated. There is also a method using a column filled with granular activated clay, but in this method, the removal efficiency of caffeine is lower than when using the same amount of activated clay powder.

  In one aspect, the present invention provides an active clay powder or acidic clay powder having an average particle size of 0.1 μm to 100 μm within a range of 20% by mass to 80% by mass based on the mass of the filter matrix, and the mass of the filter matrix. Is a filter having a filter matrix containing ultra high molecular weight polyethylene powder or high molecular weight polyethylene powder in the range of 80% by mass to 20% by mass based on

In another embodiment, the filter matrix comprises an active clay powder or an acid clay powder having an average particle size of 0.1 μm to 100 μm in a range of 20% by mass to 80% by mass based on the mass of the filter matrix, mass is the weight molecular weight in the range of 80% to 20% by weight based is ^{3.0 × 10 6 g / mol~12 ×} 10 6 g / mol, a bulk density of 0.2g ^/ cm 3 ~0.4g / Cm ³ ultra high molecular weight polyethylene powder.

In still other embodiments, the bulk density of the filter matrix is a filter in the range of ^{0.2g / cm 3 ~0.55g / cm 3} , and the scope ventilation resistance of the filter matrix of 4.0kPa~20kPa It can be a filter.

  In yet another aspect, the present invention may be a caffeine removal filter having a filter matrix comprising an activated clay powder or an acid clay powder having an average particle size of 0.1 μm to 100 μm.

  Moreover, the filtration system provided with the said filter in one side of this invention is provided.

  Furthermore, in one aspect of the present invention, a caffeine removal system including a container having an inlet for introducing a fluid containing caffeine and the filter provided in the container is provided.

  In one aspect of the present invention, a method for removing caffeine is provided which includes a step of filtering a fluid containing caffeine with the filter.

  According to the present invention, it is possible to provide a filter having excellent caffeine removal efficiency and excellent workability, a filter for removing caffeine, a filtration system, a caffeine removal system, and a caffeine removal method. .

It is a figure which shows the caffeine removal system which concerns on embodiment. It is a schematic cross section which shows an example of the removal means of caffeine which concerns on embodiment. It is a schematic cross section which shows an example of the filtration system which concerns on embodiment.

  The filter of this embodiment has a filter matrix containing an activated clay powder or an acid clay powder having an average particle diameter of 0.1 μm to 100 μm.

  The filter matrix in the present specification refers to a combination of activated clay powder or acidic clay powder and polymer particles that are sintered and / or bonded together in a self-supporting filter matrix. In the present specification, coalescence means “attaching them together” and sintering means “heating and solidifying an aggregate of solid powders”. Examples of the conditions for heating and solidifying include heating at 100 ° C to 250 ° C.

  In the filter of the present embodiment, the active clay powder or the acid clay powder is contained in the filter matrix, so that the active clay powder or the acid clay powder is mixed in the filtrate or the activated clay powder or the acid clay powder is scattered. This can be prevented and can be excellent in workability. Moreover, according to the filter of this embodiment, caffeine can be efficiently removed from the liquid containing caffeine by including the activated clay powder or the acid clay powder having an average particle diameter within the above range.

  In addition, the effect by the filter of this embodiment is based on the following knowledge of the present inventors. That is, the activated clay powder or the acid clay powder is a filter that can pass water by molding the activated clay powder or the acid clay powder as a filter matrix, even if it is simply packed in the column. Thus, the present inventors have found that caffeine can be efficiently removed from a liquid containing caffeine. In addition, by using activated clay powder or acidic clay powder as a filter matrix, the throughput can be improved compared to the conventional method in which activated clay powder or acidic clay powder is mixed with a liquid containing caffeine and stirred. The present inventors have found an effect that it is possible. In view of the fact that the activated clay powder or the acid clay powder is difficult to obtain water permeability by itself, it can be said that the above effect is unexpected.

Active clay powder or acidic clay powder having an average particle size of 0.1 μm to 100 μm has SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO, MgO, etc. as general chemical components. In the embodiment, the SiO ₂ / Al ₂ O ₃ ratio is preferably 3.0 to 12.0, more preferably 5.0 to 9.0, and Fe ₂ O ₃ is 1 Those containing 0 to 5% by mass, 0 to 1.5% by mass of CaO, and 1 to 7% by mass of MgO are preferable. In the filter of the present embodiment, “Galleon Earth V2” (trade name, manufactured by Mizusawa Chemical Co., Ltd. (Chuo-ku, Tokyo, Japan)), “Active Soil SA35” (trade name, manufactured by Toshin Kasei Co., Ltd., Chuo, Tokyo, Japan) Commercial products such as ward)) can be used.

  10-80 micrometers is preferable and, as for the average particle diameter of activated clay powder, 20-40 micrometers is more preferable.

  The filter matrix containing the activated clay powder or the acid clay powder can be obtained, for example, by a method of heat-molding a composition containing the activated clay powder or the acid clay powder and a binder using a predetermined mold.

Examples of the binder include ultra high molecular weight polyethylene powder and high molecular weight polyethylene powder. These can be used alone or in combination of two or more. In the present specification, the ultra high molecular weight means a weight molecular weight of 3.0 × 10 ⁶ g / mol or more, and the high molecular weight means a weight molecular weight of 2.0 × 10 ^{4 to} 3.0 × 10 ^6. It means g / mol. Ultra high molecular weight polyethylene powder is preferred because it is difficult to melt.

  The above weight molecular weights are "Standard Test Method for Dilute Solution Viscosity of Ethylene Polymers," D1601, Annual Book of ASTM Standards, American Society for Testing and Materials, and "Standard Specification for Ultra-High-Molecula r-Weight Polyethylene Molding and Extension. Materials, "D 4020, Annual BookofASTM Standards, American Society for Testing and Materials.

In the present embodiment, as a binder, a weight molecular weight of ^{3.0 × 10 6 g / mol~12 ×} 10 6 g / mol, a bulk density of 0.2g ^/ cm ³ ~0.4g ^/ cm 3 It is preferable to use an ultrahigh molecular weight polyethylene powder that is Ultra high molecular weight polyethylene powder can be used individually by 1 type or in combination of 2 or more types.

  In particular, by blending the above ultra-high molecular weight polyethylene powder, it is possible to satisfactorily mold the filter matrix and to ensure sufficient air permeability and water permeability of the filter matrix.

  The said bulk density means the value measured based on [Solid specific gravity measuring method] JISZ8807.

  As the ultra high molecular weight polyethylene powder, for example, commercially available products such as “GUR2126” and “GUR2122” (the trade name of Ticona (Kentucky, USA)) can be used.

The compounding amount of the activated clay powder or acidic clay powder in the composition is preferably 20% by mass to 80% by mass based on the total amount of the composition from the viewpoint of achieving both the moldability of the filter matrix and the caffeine removal performance. It is more preferable that it is 25 mass%-75 mass%, and it is still more preferable that it is 35 mass%-75 mass%. In particular, when the amount of the activated clay powder is 35% by mass to 75% by mass, caffeine can be efficiently removed in a wide range of liquid space velocity SV (hr ⁻¹ ), and caffeine is included. Larger amounts of liquid can be processed.

  The blending amount of the binder in the composition is preferably 80% by mass to 20% by mass based on the total amount of the composition from the viewpoint of ensuring the moldability of the filter matrix and the shape maintaining property after molding. More preferably, it is 75 mass%-25 mass%, and it is still more preferable that it is 65 mass%-25 mass%.

  In the composition, inorganic adsorbent powder such as diatomaceous earth and activated carbon powder, ion exchange powder such as zeolite powder and ion exchange resin, and the like can be further blended. These compounding amounts are preferably 1% by mass to 20% by mass based on the total amount of the composition.

  For example, when the ultrahigh molecular weight polyethylene powder is used as the binder as the binder, the composition is heated at 100 ° C. to 250 ° C., preferably 150 ° C. to 200 ° C. The conditions of heating for minutes to 3 hours, preferably 30 minutes to 1 hour can be mentioned. The pressure may be loaded as necessary.

  As a suitable aspect of the filter of the present embodiment, an active clay powder or acidic clay powder having an average particle size of 0.1 μm to 100 μm in a range of 20% by mass to 80% by mass based on the mass of the filter matrix; It has a filter matrix containing ultra high molecular weight polyethylene powder or high molecular weight polyethylene powder in the range of 80% by mass to 20% by mass based on the mass of the filter matrix.

Furthermore, as a suitable aspect of the filter of the present embodiment, an active clay powder or an acid clay powder having an average particle size of 0.1 μm to 100 μm in a range of 50% by mass to 75% by mass based on the mass of the filter matrix. When a weight molecular weight in the range of 25% to 50 wt% based on the weight of the filter matrix as a reference ^{3.0 × 10 6 g / mol~12 ×} 10 6 g / mol, a bulk density of 0.2 g / cm It has a filter matrix containing ultra high molecular weight polyethylene powder that is ^{3 to} 0.4 g / cm ³ . Such a filter matrix is excellent in caffeine removal efficiency and can process a larger amount of caffeine-containing liquid.

In the filter of the present embodiment, from the viewpoint of water permeability, it is preferred that the bulk density of the filter matrix is in the range of ^{0.2g / cm 3 ~0.55g / cm 3} , 0.3g / cm 3 ~0. more preferably in the range of 55 g / cm ^3, it is even more preferred in the range of ^{0.4g / cm 3 ~0.55g / cm 3} .

The filter matrix having a bulk density in the above numerical range is, for example, a binder having a weight molecular weight of 3.0 × 10 ⁶ g / mol to 12 in the range of 25% by mass to 50% by mass based on the mass of the filter matrix. × a ¹⁰ 6 g / mol, can be bulk density obtained by the inclusion of ultra-high molecular weight polyethylene powder is ^{0.2g / cm 3 ~0.4g / cm 3} .

  Further, from the viewpoint of water permeability, the ventilation resistance of the filter matrix is preferably in the range of 4.0 kPa to 20 kPa, more preferably in the range of 5.0 kPa to 20 kPa, and in the range of 10 kPa to 20 kPa. Is even more preferred.

The filter matrix having a ventilation resistance in the above numerical range is, for example, a binder having a weight molecular weight of 3.0 × 10 ⁶ g / mol to 12 in a range of 20% by mass to 80% by mass based on the mass of the filter matrix. × a ¹⁰ 6 g / mol, can be bulk density obtained by the inclusion of ultra-high molecular weight polyethylene powder is ^{0.2g / cm 3 ~0.4g / cm 3} .

  In the filter of the present embodiment, the pressure loss (MPa) when pure water is passed at 0.5 L per minute is preferably 0.005 to 0.2 MPa, and is 0.005 to 0.1 MPa. It is more preferable that the pressure is 0.01 to 0.05 MPa.

  Examples of the shape of the filter matrix constituting the filter of the present embodiment include a sheet shape, a hollow block shape, and a solid block shape.

  Next, the caffeine removal method of this embodiment will be described.

  The caffeine removal method of the present embodiment includes a step of filtering a fluid containing caffeine with the filter of the present embodiment.

  As a fluid containing caffeine, teas such as green tea, black tea, oolong tea, beverages such as coffee and cola; tea, coffee such as green tea, black tea, oolong tea; extracts from other plants; and Synthetic caffeine-containing plant extracts and the like.

In the caffeine removal method of this embodiment, when the fluid containing caffeine is a liquid, the liquid space velocity SV in the filter of this embodiment is 10 to 3000 (hr ⁻¹⁾ from the viewpoint of the caffeine removal rate. ), Preferably 50 to 2000 (hr ⁻¹ ), more preferably 50 to 1000 (hr ⁻¹ ).

  The temperature of the fluid containing caffeine can be set to 4 to 98 ° C.

  The caffeine removal method of this embodiment can be used for taste adjustment of beverages containing caffeine. In this case, the caffeine removal rate can be adjusted by appropriately setting the liquid space velocity in the filter and the filtration amount of the fluid so that a desired caffeine concentration can be obtained.

  Next, a caffeine removal system provided with the filter of this embodiment will be described.

  FIG. 1 is a diagram illustrating a caffeine removal system according to an embodiment. A system 10 shown in FIG. 1 includes a supply means 1 for supplying a fluid containing caffeine to a subsequent stage, and a fluid connected to the supply means 1 via a flow path L1 and supplied with the fluid containing caffeine. A removing unit 2 that removes caffeine and a flow path L2 that is connected to the removing unit 2 and takes out the fluid from which caffeine has been removed.

  Examples of the supply unit 1 include a raw material storage unit including caffeine such as a coffee storage tank and a tea storage tank.

  FIG. 2 is a schematic cross-sectional view illustrating an example of a caffeine removal unit according to the embodiment. The removal means 2 shown in FIG. 2 includes a container 30 having an inlet L11 for introducing a fluid containing caffeine, and the filter 20 according to the present embodiment provided in the container 30.

  Examples of the container 30 include a stainless steel container such as a 3M 1BS filter housing and a plastic container such as a 3M 1M1 filter housing.

  In the removing means 2, the filter 20 has a cylindrical shape and is held by holders 22 and 24. The fluid containing caffeine is removed from the outside of the system through the outlet L21 by removing the caffeine by passing from the outside to the inside of the cylindrical filter.

  The caffeine removal system according to the embodiment is operated under the conditions of the liquid space velocity SV and the liquid temperature in the caffeine removal method of the present embodiment described above so as to obtain a desired caffeine concentration in the filtrate. Accordingly, it is preferable to supply a fluid containing caffeine whose caffeine concentration is adjusted by dilution or concentration.

  According to the caffeine removal system of this embodiment, caffeine can be efficiently removed from a liquid containing caffeine by including the filter of this embodiment.

  According to the caffeine removal system according to the present embodiment, for example, the caffeine concentration of a beverage containing caffeine can be adjusted, and a low caffeine beverage can be produced.

  Since the caffeine removal system according to this embodiment can prevent the activated clay powder from flowing out, an apparatus for removing the activated clay powder can be omitted. Furthermore, since the caffeine removal system according to the present embodiment can prevent the activated clay powder from being scattered, the environment of the workplace can be improved.

  The caffeine removal system of the present embodiment can be changed as appropriate. For example, instead of the supply means 1, the flow path L1 can be connected to another caffeine removal system, and the treatment liquid supplied from the system can be used to further remove caffeine.

Moreover, in this embodiment, it can replace with the said supply means 1 and can supply the fluid containing the caffeine which passed through the 1 or more types of following (a)-(c) to the removal means 2. .
(A) Centrifugation means (b) Membrane filtration means such as ultrafiltration, microfiltration, microfiltration, reverse osmosis membrane filtration, electrodialysis, or biofunctional membrane (c) Adsorption of ion exchange resin, activated carbon, zeolite, etc. Filtration means having a column, filter press or spacula filled with agent

  For example, when a liquid containing caffeine is obtained by centrifugation, it can be supplied to the removing means 2 as it is.

  Furthermore, the caffeine removal system of the present embodiment can further include one or more of the above-described (a) to (c) in the subsequent stage of the removal means 2.

  Next, a filtration system provided with the filter of this embodiment is demonstrated.

  FIG. 3 is a schematic cross-sectional view showing a pot that is an example of a filtration system according to the embodiment. The pot 50 shown in FIG. 3 includes a container 48, a funnel 46 provided at the top of the container 48, and a filter unit 44 provided at the bottom of the funnel 46. The filter unit 44 includes the filter 40 of the present embodiment and a holder 42 that holds the filter 40. The funnel 46 and the filter unit 44 are detachable, and the filter unit 44 can be replaced periodically. The filter unit 44 may further include a filter other than the filter of the present embodiment. Specifically, for example, a filter for removing odors and tastes or removing particulates can be provided in the front stage of the filter of the present embodiment, and a filter for removing odors and tastes or removing particulates can be provided in the subsequent stage.

  According to the pot 50, a beverage containing caffeine can be poured into the funnel 46, and the filtrate collected in the container 48 can be obtained as a low caffeine beverage. Examples of the beverage containing caffeine include coffee; tea such as green tea, black tea, oolong tea; and cola.

  As a filtration system other than the pot type, for example, a stationary system including a container provided with an inlet and an outlet and a filter of the present embodiment provided in the container can be mentioned. The stationary filtration system is suitable for business use and can be used by being connected to a coffee machine or a bending machine.

[Preparation of filter]
Example 1
Activated clay powder having an average particle size of 25 μm (made by Mizusawa Chemical Co., Ltd. (Chuo-ku, Tokyo, Japan), trade name “Galleon Earth V2”), 65 parts by mass, bulk density is 0.23 g / cm ³ , and weight 35 masses of ultrahigh molecular weight polyethylene powder PE-1 (manufactured by Ticona (Kentucky, USA), trade name “GUR2126”) having an average molecular weight of 4.5 × 10 ⁶ g / mol and an average particle diameter of 35 μm Were mixed with a blade mixer.

  The mixed powder obtained above was filled into a cylindrical mold having an inner diameter of 53 mm and a height of 12 mm, and this was fired in an oven at a temperature of 160 ° C. for 30 minutes. Thus, a disk-shaped active clay powder filter matrix having a diameter of 51 mm and a height of 11 mm was formed, and this was obtained as the filter of Example 1.

[Filter Evaluation]
About the obtained filter, the moldability, bulk density, ventilation resistance, and water permeability were evaluated according to the following methods. The obtained results are shown in Table 1.

(Formability)
First, it was removed from the mold, it was formed as a disk-shaped filter, and it was confirmed whether the shape was maintained, and then the removed disk-shaped filter was dropped from a height of 10 cm to confirm whether there was any chipping. Formability was evaluated according to the following evaluation criteria.
A: Even if dropped from a height of 10 cm, it does not break.
B: When dropped from a height of 10 cm, part is missing.
C: Molding is not possible, and the shape after the molding process is not maintained.

(The bulk density)
[Solid specific gravity measurement method] According to JIS Z 8807, the diameter, height and weight of a disk-shaped filter are measured, and the bulk density is determined by dividing the weight by the volume determined from the diameter and height. Calculated.

(Ventilation resistance)
The obtained filter was cut into a disk shape having a diameter of 43 mm and a height of 11 mm, and this filter was 25 ° C. in accordance with the pressure loss test in Section 5.2 of “Clean air filter performance test” JIS B 9927. Under the atmospheric pressure, 17 L of air was aerated from the lower surface to the upper surface of the filter. At this time, the pressure difference between the air pressure and the atmospheric pressure on the lower surface of the filter was measured, and this was used as the ventilation resistance.

(Water permeability)
Using a hydraulic pump, the pressure loss (MPa) when pure water was passed from the upper surface of the disk-shaped filter toward the lower surface at 0.5 L / min was measured.

(Example 2)
A filter was obtained in the same manner as in Example 1 except that the blending amounts of the activated clay powder and the ultrahigh molecular weight polyethylene powder were changed to 50 parts by mass and 50 parts by mass, respectively. Evaluation similar to Example 1 was performed about the obtained filter. The results are shown in Table 1.

(Example 3)
In place of the ultra high molecular weight polyethylene powder PE-1, the ultra high molecular weight having a bulk density of 0.25 g / cm ³ , a weight average molecular weight of 4.5 × 10 ⁶ g / mol, and an average particle diameter of 115 μm. A filter was obtained in the same manner as in Example 2 except that polyethylene powder PE-2 (manufactured by Ticona (Kentucky, USA), trade name “GUR2122”) was used. Evaluation similar to Example 1 was performed about the obtained filter. The results are shown in Table 1.

Example 4
The blending amount of the ultrahigh molecular weight polyethylene powder PE-1 was changed to 25 parts by mass, the bulk density was 0.25 g / cm ³ , the weight average molecular weight was 4.5 × 10 ⁶ g / mol, and the average particle size A filter was obtained in the same manner as in Example 2, except that 25 parts by mass of ultrahigh molecular weight polyethylene powder PE-2 (manufactured by Ticona (Kentucky, USA), trade name “GUR2122”) having a particle size of 115 μm was blended. Evaluation similar to Example 1 was performed about the obtained filter. The results are shown in Table 1.

(Example 5)
The blending amount of the ultrahigh molecular weight polyethylene powder PE-1 was changed to 25 parts by mass, the bulk density was 0.47 g / cm ³ , the weight average molecular weight was 9.0 × 10 ⁶ g / mol, and the average particle size A filter was obtained in the same manner as in Example 2 except that 25 parts by mass of ultrahigh molecular weight polyethylene powder PE-3 (manufactured by Ticona (Kentucky, USA), trade name “GUR4186”) having a particle size of 45 μm was blended. Evaluation similar to Example 1 was performed about the obtained filter. The results are shown in Table 1.

(Comparative Example 1)
Instead of the ultra high molecular weight polyethylene powder PE-1, the ultra high molecular weight having a bulk density of 0.47 g / cm ³ , a weight average molecular weight of 9.0 × 10 ⁶ g / mol, and an average particle diameter of 45 μm. A filter matrix was formed in the same manner as in Example 1 except that polyethylene powder PE-3 (manufactured by Ticona (Kentucky, USA), trade name “GUR4186”) was used. However, a filter matrix could not be formed.

(Comparative Example 2)
Instead of the ultra high molecular weight polyethylene powder PE-1, the ultra high molecular weight having a bulk density of 0.47 g / cm ³ , a weight average molecular weight of 9.0 × 10 ⁶ g / mol, and an average particle diameter of 45 μm. A filter matrix was obtained in the same manner as in Example 2 except that polyethylene powder PE-3 (manufactured by Ticona (Kentucky, USA), trade name “GUR4186”) was used. Evaluation similar to Example 1 was performed about the obtained filter matrix. However, this filter matrix has a water flow resistance exceeding 0.2 MPa, has a problem with water flow, and did not function as a filter.

(Comparative Example 3)
Activated clay powder with an average particle size of 25 μm (made by Mizusawa Chemical Co., Ltd. (Chuo-ku, Tokyo, Japan), trade name “Galleon Earth V2”) is packed in a cylindrical container having an inner diameter of 53 mm and a height of 12 mm that is open on both sides. A column filter was prepared. The bulk density and water permeability of the obtained filter were evaluated in the same manner as in Example 1. The results are shown in Table 1.

  In order to evaluate the caffeine removing ability of the filter, an experiment was conducted to remove caffeine from a liquid containing caffeine according to the following procedure.

(Examples 6 to 12)
As a stock solution containing caffeine, an aqueous solution prepared with “anhydrous caffeine” reagent manufactured by Wako Pure Chemical Industries (Osaka, Japan) was prepared. Next, the stock solution containing caffeine was processed at the liquid space velocity SV (hr ⁻¹ ) shown in Table 2 using the filter of Example 1 or 4. The processing amount of the stock solution was 1360 mL when the SV was 75 hr ⁻¹ and 1400 mL under the other SV conditions.

When the SV was 75 hr ⁻¹ , the filtrate was sampled every 80 mL, and under the other SV conditions, the filtrate was sampled every 200 mL.

  The caffeine concentration in the undiluted solution and the filtrate was determined by measuring the absorbance at a wavelength of 273 nm using a DR500 spectrophotometer manufactured by HACH (Colorado, USA) for the undiluted solution or filtrate diluted 20 times. Calculation was performed based on the prepared calibration curve.

The caffeine removal rate (%) from the stock solution is obtained from the caffeine concentration of the obtained stock solution and the caffeine concentration of the filtrate, and the caffeine removal rate (%) and the treatment amount at each liquid space velocity SV (hr ⁻¹ ). The relationship with (total amount of filtrate) was plotted. An approximate curve (polynomial approximation) of the least square method was applied to this, and the processing amount at a caffeine removal rate of 90% was determined. The results are shown in Table 2.

  Table 2 shows the concentration of caffeine in the stock solution, the amount of active clay powder contained in the filter, the amount of caffeine in the filtrate, the amount of adsorbed caffeine and the amount of adsorbed caffeine with respect to the amount of active clay powder at a caffeine removal rate of 90%. Indicates the percentage.

(Reference Example 1)
Under the conditions corresponding to the contact conditions in Example 10, the stock solution was processed by a conventional method. That is, 8.3 g of an active clay powder having an average particle size of 25 μm (trade name “Galleon Earth V2” manufactured by Mizusawa Chemical Co., Ltd.) having a mean particle size of 25 μm was mixed with 438 mL of a stock solution having a caffeine concentration of 0.2207 mg / mL, and continuously for 66 seconds. Stir.

  The mixture after stirring was filtered through a 0.45 μm membrane filter (Millipore Corp. (Massachusetts, USA) MILEXHA SLHA033SS), and the caffeine removal rate was calculated by measuring the caffeine concentration of the filtrate. At this time, the removal rate of caffeine was 86.7%.

On the other hand, in Examples 6 to 12, by using the filters of Example 1 and Example 4, it is possible to obtain a filtrate from which caffeine has been removed without filtering the activated clay powder. It was confirmed that a sufficient amount of the stock solution could be processed even when the removal rate of in was 90%. In particular, when the filter of Example 4 was used, it was found that caffeine can be efficiently removed in a wide range of liquid space velocity SV (hr ⁻¹ ), and a large amount of stock solution can be processed. In the filter of Example 4, by setting the liquid hourly space velocity SV in the range of ^{75 (hr -1) ~780 (hr} -1), it has been found that can handle more stock.

DESCRIPTION OF SYMBOLS 1 ... Supply means, 2 ... Removal means, 10 ... Caffeine removal system, 20 ... Filter, 22, 24 ... Holder, 30 ... Container, 40 ... Filter, 42 ... Holder, 44 ... Filter unit, 46 ... Funnel, 48 ... container, 50 ... pot.

Claims (8)

An active clay powder or acidic clay powder having an average particle size of 0.1 μm to 100 μm in the range of 20% by mass to 80% by mass based on the mass of the filter matrix;
A filter matrix comprising: an ultrahigh molecular weight polyethylene powder or a high molecular weight polyethylene powder in a range of 80% by mass to 20% by mass based on the mass of the filter matrix. An active clay powder or acidic clay powder having an average particle size of 0.1 μm to 100 μm in the range of 20% by mass to 80% by mass based on the mass of the filter matrix;
A weight molecular weight of the mass of the filter matrix in the range of 80% to 20% by weight based is ^{3.0 × 10 6 g / mol~12 ×} 10 6 g / mol, a bulk density of 0.2 g / ^cm 3 ~ The filter of Claim 1 which has a filter matrix containing the ultra high molecular weight polyethylene powder which is 0.4 g / cm < ³ >. The bulk density of the filter matrix is in the range of ^{0.2g / cm 3 ~0.55g / cm 3} , filter according to claim 1 or 2.   The filter according to any one of claims 1 to 3, wherein a ventilation resistance of the filter matrix is in a range of 4.0 kPa to 20 kPa.   A filter for removing caffeine, comprising: a filter matrix containing an active clay powder or an acid clay powder having an average particle size of 0.1 to 100 μm.   A filtration system provided with the filter as described in any one of Claims 1-5. A container having an inlet for introducing a fluid containing caffeine;
A caffeine removal system comprising: the filter according to any one of claims 1 to 5 provided in the container. A method for removing caffeine, comprising a step of filtering a fluid containing caffeine with the filter according to any one of claims 1 to 5.

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