JPS589699B2 - Acid-base catalytic reaction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of carrying out an acid-base catalytic reaction using an ion exchange fiber based on a multicore composite fiber as a catalyst.

Ion exchange resins are widely used as catalysts in so-called acid-base catalytic reactions using acids or bases as catalysts.

Compared to ordinary acids and bases, ion exchange resins are characterized by the fact that the catalyst can be easily separated from the reaction solution, there are fewer side reactions, and continuous reactions are possible.

However, because the acidic or basic groups of ion exchange resins are much more present inside the network structure than on the surface of the resin particles, it is necessary for the reactants to diffuse into the resin, It has the disadvantage of low catalytic activity compared to acids and bases.

In particular, when the reactant is a molecule with a large molecular weight, the rate of diffusion into the interior of the resin is very low, resulting in a very low catalytic activity.

Furthermore, since the reactants and products are in contact with acidic groups and basic groups inside the resin for a long time, there is a drawback that it is difficult to sufficiently prevent side reactions.

On the other hand, the method using ion-exchange fibers as a catalyst has a larger surface area than the resin method, so the catalytic activity is higher, and the time for the reactants and products to contact acidic or basic groups is shorter, resulting in side reactions. There are very few.

Among them, ion-exchange fibers based on multicore mixed fibers made of ion-exchange polymers and reinforcing polymers and core-sheath type composite fibers with reinforcing polymers as the sheath component have high yarn strength and exchange capacity, and have high durability. Excellent chemical and solvent resistance.

However, the former ion-exchange fibers, which are based on mixed polymer fibers, have a large number of reinforcing polymers that do not have ion-exchange groups distributed near the fiber surface at a proportion of the mixing ratio, resulting in lower catalytic activity. Become.

Furthermore, the yarn strength is not fully satisfactory.

When the mixing ratio of the reinforcing polymer is decreased, the exchange capacity increases and the catalytic activity increases, but the yarn strength decreases and the fiber becomes unusable.

Conversely, if the mixing ratio of the reinforcing polymer is increased, the yarn strength will increase, but the exchange capacity will decrease and the catalytic activity will also decrease significantly.

On the other hand, ion-exchange fibers based on core-sheath type composite fibers (anabolic type, polarized type) have high catalytic activity because the vicinity of the fiber surface is composed of ion-exchangeable polymer. Since the bonding area with the reinforcing polymer is small, peeling occurs due to the introduction of ion exchange groups, and the solution has the drawback of becoming excessively cloudy due to external mechanical stimulation.

The present inventors have arrived at the present invention as a result of intensive studies aimed at improving these drawbacks.

That is, the present invention provides a composite fiber composed of two or more components in an acid-base catalyzed reaction, wherein the A component is mainly an ion exchange polymer, the B component is a fiber reinforcing polymer, and the B component is a fiber reinforcing polymer. An acid-base catalytic reaction method characterized by using as a catalyst an ion exchange fiber based on a multicore composite fiber having a multicore structure in which a plurality of are dispersed in component A and are continuous in the fiber axis direction. .

The ion exchange fiber based on the multifilamentary composite fiber of the present invention has the same multifilamentary structure no matter which fiber cross section is cut in the fiber axis direction.

In other words, the multifilamentary composite fiber that is the base material of the method of the present invention is
In the fiber cross section obtained by dissolving the component polymer in a solvent and performing wet spinning or dry spinning, or by emulsifying one component in a solution of another component and performing emulsion spinning, or by mixing both with chips and melt spinning. This is completely different from multicore mixed fibers in which the shape of the polymer mixture is unspecified.

Among the methods of the present invention, in particular, ion-exchange fibers based on multicore sea-island type composite fibers in which the ion-exchange polymer is the main component of the sea component and the reinforcing polymer is the main component of the island component have excellent durability and durability. It has excellent removability and is most preferably used.

The proportion of the island component, whose main component is a reinforcing polymer, in a multifilamentary sea-island composite fiber is usually about 10 to 90%, but if the proportion is too low, the mechanical strength will be low, and if the proportion is too high, the amount of ion exchange groups, In particular, 20
There is no particular limitation on the number of islands, which is preferably 80%, but from the viewpoint of durability and peeling resistance, a larger number is desirable, and 5 or more is particularly preferred.

Reinforcing polymers include polyester, polyamide,
Homopolymers such as poly α-olefin, copolymers and blends thereof are used.

Among these, poly-α-olefin, which has excellent chemical resistance, is most preferably used.

As the poly-α-olefin, polypropylene, polyethylene, poly-3-methylbutene-1, poly-4-methylpentene-1, etc. are preferably used.

The ion exchange polymer that is the main component of the sea component is
A polymer into which an ion exchange group can be introduced is used, and poly(monovinyl aromatic compound) is particularly preferably used.

Poly(monovinyl aromatic compounds) include styrene, α
-methylstyrene, vinyltoluene, vinylxylene,
Homopolymers such as chloromethylstyrene or copolymers of two or more thereof, and graft polymers or blends thereof are preferably used.

Furthermore, as for the sea component, in addition to these poly(monovinyl aromatic compounds), a blend with the reinforcing polymer described above may be used.

In this case, as the blend ratio of the reinforcing polymer increases, the fibers become more compacted, resulting in fibers with excellent peeling resistance, durability, and toughness, but conversely, the catalytic activity decreases, so the blend ratio is 50%. Below, about 5 to 40% is particularly preferable.

The ion exchange fiber according to the present invention refers to a fiber obtained by crosslinking and insolubilizing the composite fiber spun and drawn by any method, and introducing an ion exchange group therein.

Although the method of crosslinking and insolubilizing the conjugate fibers of the present invention is arbitrary, a method of crosslinking and insolubilizing them in sulfuric acid-water or sulfuric acid-saturated fatty acid containing a formaldehyde source is preferable.

In particular, the method of crosslinking and insolubilizing in sulfuric acid-saturated fatty acid containing a formaldehyde source is most preferred since it causes almost no side reactions.

The ion exchange group means an anion exchange group or a cation exchanger, and the introduction method thereof is arbitrary.

Examples of anion exchange groups include strongly basic anion exchange groups obtained by treating a haloalkylation group with a tertiary amine such as trimethylamine and dimethylamine ethanol, and secondary and lower class anion exchange groups such as isoprobylamine, diethylamine, piperazine, and morpholine. A weakly basic anion exchange group obtained by treatment with an amino acid is preferably used.

Cation exchange groups include chlorosulfonic acid, concentrated sulfuric acid,
Strong acidic groups obtained by sulfonation with fuming sulfuric acid, etc., sulfonic acid type moderately acidic cation exchange groups obtained by hydrolysis after reaction with phosphorus trichloride, or carboxylic acid type weakly acidic cation exchange groups, etc. is preferably used.

In acid catalytic reactions, cation exchange fibers are usually used in the hydrogen form, and in particular, strongly acidic cation exchange fibers in the hydrogen form have high catalytic activity and are most preferably used.

Moreover, it can also be used in the salt form of weakly basic anion exchange fibers.

In base-catalyzed reactions, the hydroxyl type of anion exchange fiber is usually used, and in particular, the hydroxyl type of strongly basic anion exchange fiber has high catalytic activity and is most preferably used.

Moreover, it can also be used in the salt form of weakly acidic cation exchange fibers.

Furthermore, amphoteric ion exchange fibers having cation exchange groups and anion exchange groups can also be used in suitable forms for acid-base catalyzed reactions.

In addition to the circular cross-section of the ion-exchange fibers of the present invention, non-circular cross-sections are also preferably used because they increase the surface area.

The fineness of the ion exchange fiber used in the present invention is usually 0.1.
The diameter is about 500 d, but if it is too thin, the yarn strength will be low and it will be difficult to handle, and if it is too thick, the catalytic activity will decrease, so it is particularly desirable to have a diameter of 1 to 50 d.

Further, if the fiber strength is too small, thread breakage occurs and the fiber becomes powder, so a fiber strength of 0.5 or more is preferably used.

The form of use is not limited, and it can be used in various forms such as filament yarn, punched felt, woven fabric, knitted fabric, nonwoven fabric, fiber bundle, stuffed cotton, and short fibers.

The method of the present invention is used for acid-base catalyzed reactions using ordinary acids or bases as catalysts.

For example, hydrolysis reactions of esters, carbohydrates, proteins, etc., conversion reactions of sugars, condensation reactions such as esterification, edelization, acetalization, and aldol condensation, cyanoethylation, and reactions between aldehydes, ketones, and hydrocyanic acid. Addition reactions such as cyanohydrin synthesis by addition, nitroalcohol synthesis by addition of nitrobaraffin and aldehyde, elimination reactions, rearrangement reactions such as benzidine rearrangement, nitration reactions of aromatic compounds, epoxy reactions, exchange reactions, isomerization reactions It is preferably used for

The ion-exchange fiber based on the multicore sea-island composite fiber of the present invention has high catalytic activity and extremely few side reactions because the main component near the fiber surface is composed of an ion-exchange polymer.

Furthermore, since the island components whose main component is a reinforcing polymer are continuously arranged in the fiber axis direction, they effectively contribute to fiber reinforcement and have high yarn strength.

In addition, since there are multiple core components made of reinforcing polymers, the bonding area with the ion-exchange polymer is large, making it far more resistant to peeling and durable than ion-exchange fibers based on normal core-sheath type composite fibers. Excellent in sex.

As mentioned above, the ion-exchange fiber based on the multicore sea-island type composite fiber of the present invention has, firstly, high catalytic activity, secondly, very few side reactions, and thirdly, high yarn strength. Fourthly, it has excellent peeling resistance and durability, and fifthly, it can be used in any manner.

The method of carrying out the present invention may be a fixed bed method, a continuous method or a batch method.

Examples are shown below, but the invention is not limited thereto.

Example 1 Acid catalyst was packed into a constant temperature ram (diameter 2 cm) at 60°C, regenerated with 10% hydrochloric acid, washed with hot water, and then heated to 60°C.
50% sucrose aqueous solution was flowed at various flow rates.

The effluent sugar solution was taken out, rapidly cooled, and the polarization rotation angle was measured to determine the conversion rate.

The multicore sea-island type composite cation exchange fiber of the present invention was used as an acid catalyst, and the ion exchange resin Amberlite IR- was used as a comparative example.
Table 1 shows the relationship between contact time, conversion rate, and coloration of the reaction solution when 120B was used.

The multicore sea-island type composite cation exchange fiber used as an acid catalyst was produced according to the method described below.

Melt composite spinning was carried out at 250°C so that 50 parts of polystyrene became a sea component and 50 parts of polypropylene became an island component.
6) After that, it was stretched 5 to 6 times.

The drawn yarn was immersed in a crosslinking solution consisting of 5 parts of paraformaldehyde, 25 parts of acetic acid, and 70 parts of concentrated sulfuric acid, and a crosslinking reaction was carried out at 80° C. for 4 hours to crosslink and insolubilize the polystyrene as the sea component.

The crosslinked yarn was immersed in a 5% solution of chlorosulfonic acid in trichlene, reacted at 15° C. for 2 hours, and washed with acetic acid and methanol.

Next, immerse it in a 2N aqueous sodium hydroxide solution and
A strongly acidic multicore sea-island type composite cation exchange fiber was obtained by hydrolysis at °C for 1 hour.

The cation exchange capacity of the fiber was 2.8 meq/g, the fineness was 6.3 d, the yarn strength was 1.4 g/d, and the peelability was low.

In the method of the present invention, the conversion rate reaches a factor of 80 with a contact time of 50 g-sec/ml, whereas with an ion exchange resin, a contact time of 400 g-sec/ml is required to obtain the same conversion rate.

In other words, the fibers produced according to the present invention have a catalytic activity that is about 8 times greater per duram than the resin.

In the resin method, the longer the contact time and the higher the conversion rate, the greater the coloration of the reaction solution and resin, whereas in the method of the present invention, no coloration due to such side reactions was observed.

Example 2 Acid catalyst was packed into a constant temperature ram (diameter 2 cm) at 30°C,
After regeneration with 10% hydrochloric acid and washing with hot water,
Aqueous methyl acetate solution of 5% was flowed at various flow rates.

The effluent was taken out and the concentration of acetic acid produced was determined by neutralization titration.

The multicore sea-island type composite cation exchange fiber of the present invention was used as an acid catalyst, and the ion exchange resin Amberlite IR- was used as a comparative example.
Table 2 shows the relationship between contact time and acetic acid concentration when 200 (MR type) is used.

The multicore sea-island type composite cation exchange fiber used as an acid catalyst was produced according to the method described below.

After melt composite spinning at 250°C (number of islands: 16) such that a blend of 49 parts of polystyrene and 12 parts of polypropylene becomes a sea component and 39 parts of polypropylene becomes an island component,
It was stretched 6 times.

Thereafter, a strongly acidic multicore sea-island type composite cation exchange fiber was obtained by reaction treatment using the method shown in Example 1.

The cation exchange capacity of the fiber was 2.7 milliequivalents/g, the fineness was 6.2d, and the yarn strength was 1.3g/d, and no peelability was observed because polypropylene was blended with 20 parts in the sea component. .

The fibers were non-aqueous and did not change even after long-term use.

In the method of the present invention, the acetic acid concentration reaches 0.28 mol/l with a contact time of 200 g·sec/ml, whereas with the ion exchange resin, almost the same concentration is reached with a contact time of 400 g·sec/ml.

In other words, the fibers produced according to the present invention have a catalytic activity that is about 1.5 to 2 times greater than that of the resin.

Example 3 6 g of base catalyst was packed into a thermostatic column (diameter 2 cm) at 60°C, regenerated with 10 g of sodium hydroxide aqueous solution, washed with hot water, and then added with 25% glucose aqueous solution at 60°C for a contact time of 150 g.・600m to achieve sec/ml
l flowed.

The effluent sugar solution was taken out from time to time, rapidly cooled, and fructose was determined by the Anthrone method and the cysteine-rubasol method to examine the conversion rate to fructose.

The multicore sea-island type composite anion exchange fiber of the present invention was used as a base catalyst, and the ion exchange resin Amberlite IR was used as a comparative example.
．． Table 3 shows the relationship between the amount of effluent and the conversion rate and the coloring property of the catalyst when A-401 was used.

The multicore sea-island type composite anion exchange fiber used as a base catalyst was produced according to the method described below.

The drawn yarn obtained by the method of Example 2 was immersed in the same crosslinking solution as in Example 1, and a crosslinking reaction was carried out at 80° C. for 2 hours.

Next, the crosslinked yarn was immersed in a solution consisting of 85 parts of chloromethyl ether and 15 parts of stannic chloride, and reacted at 30° C. for 1 hour.

After the reaction was completed, it was washed with 10% hydrochloric acid, distilled water, and acetone.

The chloromethylated yarn was immersed in a 30% trimethylamine aqueous solution and aminated at 30° C. for 1 hour to obtain a strongly basic multicore sea-island type composite anion exchange fiber.

The anion exchange capacity of the fiber was 2.5 meq/gs, the fineness was 6.3d, the strength was 1.4g/d, and no peelability was observed.
It was strong.

From Table 3, it can be seen that the method of the present invention has higher catalytic activity than the resin method, with less generation of colored substances and organic acids due to side reactions, and a small decrease in catalytic activity.

Example 4 Polyethylene glycol 100 with number average molecular weight 4000
A hydroxyl group-type hydrous base catalyst is added to a solution of 130 parts of acrylonitrile and 130 parts of acrylonitrile, and the mixture is kept at 30°C and stirred vigorously for 5 hours.

Then, the catalyst is removed by passing through the mouth.

The oral fluid was distilled under reduced pressure at a pressure of 50 mmHg and a temperature of 70°C to remove excess acrylonitrile, and then further distilled at a pressure of 5 mHg.
A dianoethylated product was obtained by drying for 10 hours under conditions of Hg and a temperature of 70°C.

When 3 parts of the multicore sea-island composite anion exchange fiber of the present invention is used as a base catalyst, the product is a colorless solid with a hydroxyl value of zero, and polyethylene glycol is cyanoethylated without any side reactions, resulting in substantially 100% cyanoethylation. Conversion to β-cyanoethoxypolyether was confirmed.

On the other hand, ion exchange resin Amberlite I was used as a base catalyst.
When 10 parts of RA-410 is used, the product has a hydroxyl value of 2
．． It was a yellow solid with a concentration of 8 KOH/g.

That is, the product was colored due to side reactions such as homopolymerization of acrylonitrile and the like, and the conversion rate from polyethylene glycol to β-cyanoethoxy polyether was about 90%.

It can be seen that the method of the present invention has high catalytic activity and very few side reactions.

The multicore sea-island type composite anion exchange fiber used as a base catalyst was obtained by soaking the chloromethylated yarn obtained by the method of Example 3 in a 30% dimethylaminoethanol aqueous solution and reacting at 70°C for 2 hours. .

The anion exchange capacity of the fiber was 2.4 milliequivalents/g, the fiber was 6.5 d, the strength was 1.5 g/d, and no peelability was observed.
It was strong.

Claims (1)

[Claims] 1 A composite fiber consisting of two or more components in an acid-base catalyzed reaction, in which the A component is mainly an ion exchange polymer, the B component is a fiber reinforcing polymer, and the B component contains the A component. An acid-base catalytic reaction method characterized by using, as a catalyst, an ion exchange fiber based on a multicore composite fiber having a multicore structure in which a plurality of fibers are dispersed in a fiber and are continuous in the fiber axis direction.