DE1168081B - Process for increasing the capacity of cation exchangers containing a maximum of one sulfonic acid group per aryl nucleus - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN JSflTWWl · PATENT OFFICE Internat. Class: G 08 f

EDITORIAL

German class: 39 c -25/01

Number: 1168 081

File number: F 30357IV d / 39 c

Filing date: January 21, 1960

Opening day: April 16, 1964

There are various methods of making cation exchangers crosslinked by sulfonation Polymers of vinyl aromatic compounds, such as styrene, vinyl toluene and chlorostyrene, are known. In the basic USA.-Patent 2 366 007 is indicated here that, for example, in the sulfonation of a styrene polymer with chlorosulfonic acid, a product is obtained which is aromatic Core contains 1.77 sulfonic acid groups, with only the weight increase of the starting resin for this statement is used.

"In contrast, P e ρ ρ e r (J. Applied Chem. 1 [1951], pp. 124 to 132) found that sulfonation of polymers of vinyl aromatic compounds with concentrated sulfuric acid, a maximum of one sulfonic acid group per aromatic nucleus is introduced can be. Kressman comes to the same conclusion (C. C a 1 m ο η and T. R. E. K r e s s m a n, "Ion Exchangers in Organic and Biochemistry", New York, 1957, p. 21) and Fr. H e 1 f e r i c h ("Ion Exchange", Weinheim, 1959, Vol. I, p. 32). The investigation of the commercially available cation exchangers, which are declared as sulfonated crosslinked polystyrenes has to be in accordance with the latter Publications show that these cation exchangers also have a maximum of one sulfonic acid group each contain aromatic nucleus. Since the partial introduction of further sulfonic acid groups each aromatic core may be of technical interest in terms of increasing capacity the example of sulfonation with 10% described in US Pat. No. 2,366,007 Divinylbenzene cross-linked polystyrene with chlorosulfonic acid in various embodiments within reworked within the framework of the general description. In doing so, the acid could be used carefully freed and completely hydrolyzed and dried samples neither confirmed the weight information more than one sulfonic acid group per aromatic nucleus was detected by sulfur analysis will.

According to German patent specification 963 020, cation exchangers are obtained by polymerizing shoots Sulfonated styrenes. In this case, as for example from Example 3 the patent can be seen, copolymers of Srtyol, butadiene and small amounts of divinylbenzene be used. The sulfonation products obtained according to this example should per Aryl nucleus contain more than one sulfonic acid group. However, this information could be based on our own Attempts are not confirmed. Moreover, own

Procedure for increasing the capacity of
a maximum of one sulfonic acid group per aryl nucleus
containing cation exchangers

Applicant:

Paint factories Bayer Aktiengesellschaft,
Leverkusen

Named as inventor:

Dr. Herbert Corte, Opladen,

Dr. Otto Netz, Cologne,

Dr. Hans Seifert, Bergisch-Neukirchen

these known products have the disadvantage that they have a very high swelling capacity. From the U.S. Patent 2,645,621 is the sulfonation of copolymers of styrene and conjugated diolefins known. According to the information in Example 1 of the patent, this should average about 1.5 sulfonic acid groups are introduced per aryl nucleus.

This information cannot stand up to verification either.

It has now been found that the capacity of cation exchangers containing a maximum of one sulfonic acid group per aryl nucleus on the basis of vinylaromatic polymers crosslinked with nonconjugated aromatic polyvinyl compounds can be increased if these cation exchangers bearing sulfonic acid groups are used with as much oleum and / or SO ₃ at temperatures between 0 and 200 ° C treated so that the sulfating acid still contains free SO ₃ after the sulfation has ended.

Using this process it is possible to introduce a second sulfonic acid group into the aromatic nuclei of the polymers mentioned. The process can be applied quite generally to monosulphurisation products of the polymers mentioned.
Examples of aromatic vinyl compounds which are suitable for the preparation of the polymers or copolymers are: styrene, vinyltoluenes, vinylnaphthalenes, vinylethylbenzenes, methylstyrenes, vinylchlorobenzenes, vinylxylenes. Polyvinyl compounds, for example divinylbenzenes and divinyltoluenes, are suitable as nonconjugated polyvinyl compounds. The polymers can be in the presence or absence of solvents or

409 559/595

3 4

Dispersants as well as with the use of B e i s t> i e 1 2

different polymerization initiators, such as inorganic or organic peroxides, persulfates under exactly the same conditions as in have been presented. In Example 1, an 8.5% divinylbenzene crosslinked "monosulfation of this vinylaromatic poly-5 poly-p-vinyltoluene in bead form initially with concentrates can be sulfated according to various known for this purpose trated sulfuric acid. The thus obtained Methods be done, for example by sulphonation product had a maximum capacity of 2.2 meq / ml of the polymers with concentrated sulfuric acid H-form.

or chlorosulfonic acid or, if appropriate, by the subsequent further treatment with

Copolymerization of sulfonic acid-carrying oleum 65% oleum became a cation exchanger with the copolymerizable aromatics. It is not the subject of the invention with a maximum capacity of 3.3 meq / cm ^{3 H-form.} obtained (6.4 meq / g H-form).

According to the process according to the invention, a little SO ₃ or oleum is used, so that

Cation exchangers bearing sulfonic acid groups, the reaction mixture contains little or no expediently a _{sulfonation free SO 3} with concentrated 15, then the further sulfonation only takes place sulfuric acid produced according to known processes to a small extent or is omitted with re-sulfonation product, which is used here from the stand completely.
Reaction mixture does not need to be isolated. B is ρ ie 1 3

It is preferable to work with such a sulfur

trioxide concentration so that the sulphonation acid after the sulphonation in Example 1 still contains between 10 and 50% 65% strength oleum only 1000 cm ³ with otherwise the same free SO ₃ ^{instead of the 1300 cm 8} sulphonation completed. The temperatures to be maintained in the conditions according to the invention, the cation process has a maximum capacity of 2.8 meq / cm * wide ranges in the exchanger, ie temperatures of H-form (6.1 meq / g H-form). When using from 0 to 200 ⁰ C can be used, although the practically only 500 cm ^s 65% oleum will only reach a maximum temperature range of interest of 2.45 meq / cm ³ H-form only 50 to 120 ⁰ C. The reaction time is oriented (5.4 meq / g H-form).

once depending on the nature of the resin used, In addition, the degree of crosslinking has an

the concentration of the oleum used and the flow on the extent of the disulfation in the sense of the respective reaction temperature and is in the 30 that less crosslinked cation exchanger in the general between 1 and 50 hours. It will result in a higher percentage increase in the maximum capacity expediently in the usual way by sampling,
certainly. After this treatment, “. · \ A

remove carefully with water or sulfuric acid- ^

the concentration is diluted and the reaction product 35 is isolated in a manner known per se which is crosslinked with only 6% divinylbenzene. According to the process according to the invention, the monosulfation product has a maximum capacity of resins in which the H-form is ^{1.9 meq / cm 3 per aromatic nucleus.} The cation exchanger obtained after treatment with at least 1.3, but generally 1.5 to 1.8 SuI-65% strength oleum possessed fonsäuregruppen are present. Accordingly, 40 have a maximum capacity of 2.5 meq / cm ³ H-form obtained by the present process (6.3 meq / g H-form).
Exchange resins containing sulfonic acid groups a ^ ■ ■ 1 ^

significantly increased capacity compared to previously known P

Exchangers with sulfonic acid groups. A cross-linked with 16 ° / ₀ divinylbenzene in

45 Perlform provided monosulphurisation according to example 1

Example 1 a cation exchanger with a maximum capacity

ity of 2.9 meq / cm ³ H-shape. The one after treatment

In a sulphonation flask with stirrer, thermometer with oleum had a cation exchanger and descending cooling was allowed to 500 g of a ^{polystyrene crosslinked with a maximum capacity of 3.55 meq / cm 3} H-form 8.5% divinylbenzene in bead form 50 (5.8 meq / g H-shape).
with 200 cm ³ of ethylene chloride for 8 hours under stirring ■ _R · 1 ή

sources. Then 1300 cm ^{3 of} concentrated sulfur ^

acid was added and under stirring over a 6 ° / ₀ divinylbenzene crosslinked poly-p-vinyl-

Heated to 120 ^° C. for 3 hours. At about 85 ° C, toluene begins to distill in bead form, which is supplied on treatment with concentrated ethylene chloride. After 4 hours 55 trated sulfuric acid according to Example 1 a cation heating at 120 ⁰ C the Monosulfierung is completed. Exchanger with a maximum capacity of 1.8 meq / A sample of the reaction product has an H-shape ^{according to cm 3.} Further treatment with 65% dilution with water, a total capacity of oleum gave a product with a maximum capacity of 2.3 meq / cm ^{3 of} the H-form (6.4 meq / g H-form). of 2.8 meq / cm ³ H-shape (6.6 meq / g H-shape).

After completion of the Monosulfierung was left at 60 in a conventional manner The monosulfierte cation--cool 8O ⁰ C and gradually exchanger at this temperature can also be first isolated as such in 1300 cm ³ of 65% oleum are added dropwise, and are temperature and then, after drying of the treatment temperature increase to about 100 ° C occurred. Subsequently subjected to oleum,
^{was heated to 100 0} C for a further 4 hours, then. .

cooled and the reaction mixture very slowly with 65 example /

Water diluted. A by sulfation with chlorosulfonic acid from with

The cation exchanger obtained had a 10% divinylbenzene crosslinked polystyrene and a maximum capacity of 3.0 meq / cm ³ H-form. final hydrolysis of sulfochloride obtained

Commercially available cation exchanger in bead form, which was in the Na form, was converted into the H form by treatment with 10% strength hydrochloric acid and this was ^{dried at 100 °} C. in a vacuum. The dried product was introduced into 41% strength oleum and ^{heated to 100 °} C. for 4 hours with stirring. After cooling, the reaction mixture was diluted very slowly with water and the cation exchanger was washed free of acid.

The maximum capacity of the cation exchanger thus obtained is 2.9 meq / cm ^{3 of} the H-form (5.8 meq / g H-form), while the cation exchanger used had a maximum capacity of 2.2 meq / cm ^{3 of} the H-form.

The process is also very beneficial when applied to cation exchangers with a sponge structure, as available from German patent application F 22878 IVb / 39c (Auslegeschrift 1 113 570) are off, as the post-treatment with oleum is normally caused by the sponge structure lower volume capacity compared to the corresponding exchangers with gel structure, if can be increased so that it is equal to that of normal cation exchangers.

Example 8

500 g of a bead polymer with a so-called sponge structure and a divinylbenzene content of 8% obtained by copolymerization of divinylbenzene and styrene with the addition of 60 percent by weight white spirit (based on the weight of the monomers) was ^{swollen in 300 cm 3 of} ethylene chloride for 1 hour and then in a sulphonation flask with stirrer , Thermometer and descending cooler with 1500 cm ^{3 of} concentrated sulfuric acid heated ^{to 120 0 C within 3 hours.} At about 83 ⁰ C, the distillation of Äthylenchlorids begins. The product obtained in 12O ⁰ C for 4 hours, after heating has a maximum capacity of 1.6 meq / cm ³ H form.

After heating at 12O ⁰ C was allowed to cool to about 8O ⁰ C and then gradually 1500 cm ³ of 65% oleum are added dropwise, the temperature rose to about 100 ⁰ C. After additional 4 hours of heating at 100 ⁰ C, the reaction mass was cooled and then carefully diluted with water. The cation exchanger obtained with a sponge structure had a maximum capacity of 2.25 meq / cm ³ H-form (5.8 meq / g H-form).

Example 9

The sulphonation of an 8% divinylbenzene-crosslinked bead polymer with concentrated sulfuric acid, but with the addition of 100 percent by weight white spirit (based on the weight of monomers used) as starting material, produced a cation exchanger with a maximum capacity of 1.4 meq / cm ³ H shape. After treatment with 65% oleum, as in Example 8, a cation exchanger with a maximum capacity of 2.0 meq / cm ³ H-form was obtained (5.8 meq / g H-form).

Claims (2)

Patent claims: 1. A method for increasing the capacity of cation exchangers containing a maximum of one sulfonic acid group per aryl nucleus on the basis of vinylaromatic polymers crosslinked with nonconjugated aromatic polyvinyl compounds, characterized in that. that these sulfo-containing cation exchanger or SO with as much oleum and / treated at temperatures between 0 and 200 ⁰ C ₃ that the Sulfiersäure after completion of the sulfonation reaction or free SO _3. 2. The method according to claim 1, characterized in that the treatment with oleum and / or SO _{3 is carried out} directly after the preparation of the cation exchangers without their purification or isolation. .Considered publications:
German Patent Nos. 915 267, 963 020;
U.S. Patent Nos. 2,366,007, 2,645,621, 2,678,306, 2,868,737. When the registration was announced, three pages of the test report were laid out. 409 559/595 4.64 © Bundesdruckerei Berlin