JPS63214350A - Hydrophilic adsorbent - Google Patents

Abstract

PURPOSE:To enhance the capacitor for adsorbing, separating and purifying macromolecules, by constituting a short columnar substance having a specific range of diameter and length/diameter ratio of an ultrafine fiber bundle having a specific fiber diameter and a cylindrical body receiving said fiber bundle at the open end thereof. CONSTITUTION:An aqueous solution having polyvinyl alcohol and partially saponified polyvinyl alcohol mixed and dissolved therein is spun into an extremely thick fiber which is, in turn, extruded into a coagulation bath. After the extremely thick fiber is treated with a strong alkaline aqueous solution, the treated fiber is cut into a predetermined length and washed to obtain a polyvinyl alcohol porous body. An ion exchange group is introduced into said porous body to prepare an adsorbent. This adsorbent has a short columnar shape having a diameter of 100-5,000mum and a length/diameter ratio of 0.3-3 and is formed of ultrafine fiber bundles each having a fiber diameter of 0.01-10mum arranged in the axial direction and a cylindrical film with a thickness of 5-50mum receiving said fiber bundles opened at both ends and the ion exchange group thereof is 0.3meq/g or more.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel adsorbent, and more particularly to a new and improved hydrophilic adsorbent that is effective for adsorption, separation, and purification of bio-related macromolecules and physiologically active substances such as enzymes.

Currently used for adsorption 2 separation and purification of biologically related substances.

Hydrophilic matrix ion exchangers such as ion-exchange cellulose and Sephadex have been praised for their lack of non-specific adsorption properties.

However, in order to increase the adsorption amount of these materials, especially when targeting macromolecules such as enzymes, it is necessary to choose a material with a low degree of crosslinking or a type with a large specific surface area. Inevitably, the degree of swelling of the adsorbent is high and its mechanical strength is poor, and in the latter case, effective means of creating porosity, such as that found in lipophilic styrene-divinylbenzene ion exchange resins, cannot be taken. Inevitably, it will be on the particle size side or on the fiber side, and problems in handling such as water permeability cannot be avoided.

Furthermore, since the above-mentioned materials are made from natural products, there are limits to their resistance to decay and chemicals, and there are also physical limitations on wI, so they are not necessarily satisfactory for industrial use.

In view of the current situation, the present inventors are currently researching materials that do not have these limitations, and have found that extremely thick and extremely fine fiber bundles obtained by phase separation spinning of polyvinyl alcohol have favorable characteristics. As a result of further pursuit of the details, we finally arrived at the present invention. That is, the present invention.

(1) The outer shape is a short columnar shape with a diameter of 100 to 5000μ and a length/diameter ratio of 0.3 to 3; (2) Ultrafine fibers with fiber diameters of 0.01 to 10μ in which the short columns are arranged in the axial direction. With a bunch.

The fiber bundle is made of a cylindrical membrane with a thickness of 5 to 50 μ, which stores the fiber bundle with the N end open, and (3) is made of polyvinyl alcohol and has an ion exchange group of 0.3 a*q/ or more introduced therein. The adsorbent of the present invention is a hydrophilic adsorbent characterized by:

1) Due to its pellet-like morphology, it can be used in an open column system, which is the basis for industrial large-scale processing, and in this case, the packing density is high.

It has good water permeability and can be backwashed.

2) Regarding the adsorption amount of macromolecules such as enzymes, even if the ion exchange capacity is small, the adsorption amount is far greater than that of a high porous type ion exchange resin of similar size.

(This is thought to be due to the huge specific surface area of the ultrafine i-fiber bundle9, and the gaps between these fibers are connected straight and true, creating a structure that is advantageous for the penetration and diffusion of macromolecules.) 3) Decay It is a hydrophilic adsorbent with excellent chemical resistance.

It has characteristics such as.

The present invention will be explained in more detail below.

First, the fine a-fibers constituting the adsorbent of the present invention have a diameter of 0.0 [
The fiber bundle must be continuous in the axial direction with a thickness of ~10μ.

Namely, if the fiber diameter of the fine fibers constituting the adsorbent of the present invention is too small, the diffusion and penetration of the target object during the adsorption/desorption process will be slow, and in the case of macromolecules such as enzymes, clogging will occur near the entrance. Conversely, as the thickness increases, adsorption of macromolecules decreases due to a decrease in specific surface area. Therefore, the fiber diameter is at least 0. O1μ is necessary and preferably 0.1 to LOμ.

In order to facilitate diffusion into the interior of the adsorbent, each fine fiber may be independent from end to end, or may adhere to each other in places to form a three-dimensional net-like structure as a whole. The fibers may be continuous in the axial direction, and the fiber diameter does not need to be uniform.

In fact, it may be preferable for the fiber diameter distribution to have a certain degree of spread.

Next, if the thickness of the cylindrical membrane that stores the ultrafine fibers with both ends open is too thin, the physical strength of the adsorbent will decrease, and if it is too thick, the composition ratio of the ultrafine fibers will decrease. Therefore, it is preferably 5 to 20μ. The spaces formed as gaps between these fine fibers (porosity) are 209 or more8
It is preferable that it is 0X or less.

The porosity can be measured by the mercury intrusion method, but as a convenient method, the porosity can be measured by I [micro I! It can also be estimated by llIM4.

Ion exchange groups include acidic groups such as snosulfonic acid groups, carboxyl groups, and phosphonic acid groups, or bases such as primary, secondary, and tertiary amino groups, quaternary ammonium groups, guanidyl groups, and pyridyl groups. In addition, it may be a gastrogenic group such as aminocarboxylic acid, and furthermore, these ion exchange groups may have two or more types.

If the number of these ion exchange groups is small, the macromolecular adsorption capacity will be low even if the specific surface area is large; conversely, if the number of these ion exchange groups is too high, the swelling ratio of the adsorbent will increase and the physical strength will decrease.
Preferably it is 0.3-3 msq/g.

Regarding the diameter of the adsorbent of the present invention, if the diameter is small, the pressure loss during column operation will be large, as is seen even with ordinary fine resins. On the other hand, if the diameter is too large, the liquid permeability is good, but the utilization rate is lowered, so the diameter should be 100 to 5000μ.

Regarding the length, if the ratio of diameter to length (aspect ratio) is large, when treated as a slurry, entanglement effects will occur between adsorbents, making it difficult to backwash, etc.
There is a tendency for the utilization rate of the central area to decrease as the distance from the entrance hole (cutting plane) of Ill & East increases.

On the other hand, when the 7 spectral ratio becomes small, the utilization efficiency of exchange groups per unit column volume increases, but when it becomes extremely small, the column becomes thin and there are many cases of breakage and falling out of the stored ultrafine mm. Therefore, the aspect ratio.

It needs to be 1111 between 0.3 and 3.

Note that when the cross section of the fiber is not a perfect circle, the diameter is treated as the short axis, and the aspect ratio is the ratio of the short axis to the fiber length.

The adsorbent of the present invention having the above-mentioned characteristics can be produced by a secondary method.

That is, first, an aqueous fs solution in which polyvinyl alcohol and partially oxidized polyvinyl alcohol are mixed and dissolved is spun, or an aqueous solution in which polyvinyl alcohol and partially oxidized polyvinyl alcohol are mixed and dissolved is coagulated into extremely thick am using a composite spinning method using a nozzle for seabird fibers or a sudachiku mixer. Spun in a bath.

Next, this extremely thick fiber is immersed for a short time in a strong alkaline aqueous solution such as caustic soda to linearize the partially saponified polyvinyl alcohol in the surface layer, forming a surface layer of completely linearized polyvinyl alcohol in the surface layer. and wash with water to dissolve and remove partially saponified polyvinyl alcohol.

The vAR agent of the present invention can be obtained by subjecting the polyvinyl alcohol porous material thus obtained to an insolubilization treatment, if necessary, and then introducing an ion exchange group.

In the above method, it is also possible to obtain the desired product without introducing an ion exchange group by using polyvinyl alcohol which already has an ion exchange group as the polyvinyl alcohol alone or in combination.

The polyvinyl alcohol that can be used in the method of the present invention needs to be a polyvinyl alcohol with a high degree of tt and amization and an appropriate degree of polymerization.

Specifically, the saponification agent is 95 molX or more, preferably 98 molX or more, and the degree of polymerization is 800 to 30
It is 00.

As these polyvinyl alcohols, polyvinyl alcohols in which lomolX or less of the above-mentioned ion exchange groups are introduced by copolymerization or reaction can also be used.

On the other hand, as a two-part saponified polyvinyl alcohol.

It must have some degree of stringability and be easily removed by washing with water, specifically, the degree of mirroring is 1±95a+o 1%.
The degree of polymerization is preferably 80"90mo1% or less.
200G partially saponified polyvinyl alcohol.

There is no particular restriction on the method of introducing the ion exchange group; in other words, a known method that utilizes the reactivity of the water group of polyvinyl alcohol is generally used to process the shaped product of the present invention and introduce the ion exchange group. However, the adsorbent of the present invention may be formed by using polyvinyl alcohol into which ion-exchange groups have been introduced in the form of an aqueous solution, pellets, powder, etc., alone or by blending it. - may be copolymerized or graft polymerized with vinyl acetate.

The thus obtained adsorbent of the present invention is as follows.

1) Due to its pellet-like morphology, it can be used in an open column system, which is the basis of industrial large-scale processing, and in this case, the packing density is high.

It has good water permeability and can be backwashed.

2) Even if the ion exchange capacity is small, the amount of adsorption of macromolecules such as 9 elements is far greater than that of a high porous type ion exchange resin of similar size.

3) It is a tree-friendly adsorbent that does not rot and has excellent chemical resistance.

What are the features of this invention? 5. It will contribute to the future development of the field.

Although the method for producing the adsorbent of the present invention is not limited to the following description, it will be explained more specifically through the following examples.

Example-1 Completely saponified polyvinyl alcohol (saponification degree 99.9mol
%, average polymerization Jt 1200) and partially saponified polyvinyl alcohol (linearized JIE 119mo 1%, average polymerization degree 50
A stock solution was prepared by mixing and dissolving 0) with hot water so that the weight ratio was 4Q/GG.

This stock solution was immediately spun into a 28vL% ammonium sulfate aqueous solution from a 1200μ nozzle to obtain a very thick aR fiber with a circular cross section.
This was immersed in a caustic soda aqueous solution of LN at 30° C. for 3 minutes to perform saponification treatment at the back door.

Then, it was neutralized with an L/10N aqueous hydrochloric acid solution, and further washed with water. Furthermore, this sample was added to 45% to improve water resistance.
Place it in a wtX ammonium sulfate aqueous solution and heat it at 135°C for [time @], then use a guillotine cutter to length Q, 5+u.
I cut it into + and made it into a very thick @Wi fiber.

This was washed repeatedly with hot water at 30°C to elute the 9-partly saponified polyvinyl alcohol, and the ultra-fine J
A structure consisting of a cylindrical membrane containing aIMAJIIl and 29 was obtained.

In addition, for those for which the immersion treatment in the back soda aqueous solution is omitted, there is no cylindrical membrane at this stage and the fibers become scattered fine fibers.1! In the case of the longest polyvinyl alcohol, it is difficult to dissolve and remove the two-partly saponified polyvinyl alcohol, and even if it were removed, the following progress of pressure reaction would be a problem.

This structure was mixed with 2% bromoacetal and 15% salt.
In a salt bath containing 9 wt 20 soda tX, sulfur a20
Formalization treatment was performed in 1 m of wtX water at a bath ratio of 1150 at 60°C for 2 hours. After this, dimethylamine 1
5 wtX, ammonium sulfate 5 wtX (7) in aqueous solution, bath ratio 1
730.

A reaction was carried out at 80° C. for 20 hours to introduce a tertiary 7-mino group.

Thus, it has a circular cross section with a diameter of about 500 μm and an outer shape of about 900 μm in length, and is composed of a cylindrical membrane with a thickness of about 20 μm that stores long fiber bundles with a thickness of 0.01 to 10 μm and a cylindrical membrane with a thickness of about 20 μm. About 65, add tertiary amino group to 0.8 meq/g
A hydrophilic adsorbent having the following properties was obtained.

'A Example-2 Completely linearized polyvinyl alcohol (saponification degree 99.9m).

tX, m synthetic leather 120G) and dimethylaminoacetalized polyvinyl alcohol CI! Elementary content 0.84vtX
, saponified Ix, 99.9soLXiE degree 120G) in a weight ratio of 25/7S"t' tflF!L34
．． Aqueous solution of 2 wt
A 42 wt Combined diameter [200
The fiber was discharged from a nozzle with μ and L holes into a coagulation bath containing 30 wt ammonium sulfate to obtain a very thick fiber with a new circular surface.

This was immersed in an aqueous LN caustic soda solution at 30°C for 3 minutes, immersed in L/1ON-hydrochloric acid for 110 seconds, and washed with running water for 10 minutes.
After that, heat treatment was performed for 1 hour at 135°C in an aqueous solution of 45 soda and ammonium sulfate to saponify the surface of the ultra-thick fibers and improve water resistance. Cut into 0.51 pieces and heat at 30℃
(1) Washing with water was repeated to elute the partially saponified polyvinyl alcohol (2).

Thus, it has a circular cross section with a diameter of 400μ and a length of 500μ, is covered with a cylindrical membrane with a thickness of about 40μ, and has a cylindrical membrane of 0.01 to 10
A hydrophilic adsorbent having ultrafine side fiber bundles of μ and 0.45w5q/g of tertiary 7-mino groups with a porosity of 60% was obtained.

Example 3 Hydrophilic adsorbent obtained in Examples 1 and 2 and a commercially available hydrophilic adsorbent having the same ion exchange group (0°05+s+i
Spherical shape: Sephadex AG-2, Fermacia, Fine Chemicals, hydrophobic adsorbent (0.4~0.
Invertase (manufactured by Toyobo) saturation adsorption amount (U element adsorption X per column volume at X position) and liquid permeability , ion exchange capacity,
Furthermore, the removability was determined and compared. The results are shown in Table-1.

Skewer Column Liquid Permeability Each adsorbent was packed into two columns and the two liquid permeability was observed.

Items with good liquid permeability: Ol Items with poor liquid permeability: x Skewer Enzyme saturated absorption amount: The adsorbent was immersed in an enzyme aqueous solution at 30°C for 20 hours, and the amount of enzyme before and after was measured by UV spectrum. It was quantified and calculated from the difference.

Skewer adhesion: Invertase is saturated and adsorbed.
12 in a LX-NaCl aqueous solution at 30°C at a bath ratio of 1150.
The invertase that had fallen into the aqueous solution was determined by immersing it vertically for a certain amount of time. Inn Sunset 0x or more o
, those of 50 to 80% were designated as F, and those of 50x or less were designated as X.

[Brief explanation of the drawing]

In the latter case, long aat fibers are formed in the fiber axis direction. 1. Indication of the case Japanese Patent Application No. 62-45207 2. Name of the invention Hydrophilic adsorbent 3. Person making the amendment Relationship to the case Patent applicant address 3-1-2 Kyobashi, Chuo-ku, Tokyo Name: Nichibi Co., Ltd. Date of May 26, 1986 6. Contents of amendment 1) In the column of attached documents to the application, the words "r (2) 1 copy of drawings" will be deleted. 2) Delete the entire text below "4. Brief explanation of the drawings J" on page 15 of the specification. 3) Delete all sections of the drawings.

Claims (1)

[Claims] (1) The outer shape is a short columnar shape with a diameter of 100 to 5000μ and a length/diameter ratio of 0.3 to 3; (2) Ultrafine fibers with fiber diameters of 0.01 to 10μ in which the short columns are arranged in the axial direction. a cylindrical membrane with a thickness of 5 to 50 μ that stores the fiber bundle with both ends open, (3) made of polyvinyl alcohol and introduced with ion exchange groups of 0.3 meq/g or more A hydrophilic adsorbent characterized by: