DD211352A1 - METHOD FOR PRODUCING ION EXCHANGERS WITH AMINOPHOSPHONIC ACID GROUPS - Google Patents

Abstract

The invention relates to a process for the preparation of ion exchangers with Aminophosphonsaeuregruppen having particularly good capacity for metal ions. The ion exchangers are prepared by reacting weakly basic anion exchangers with amino groups with formaldehyde and the like. Halogenated alkyl esters of the phosphorous acid in a suspension with or without the addition of phosphorous acid at temperatures of 50 to 100 degrees C. Particularly suitable esters are bis-2-chloroethyl phosphite and tris-2-chloroethyl phosphite.

Description

УЕВ CHEMJTi ^ tIBINAT BITTERFELD Bitterfeld, 'j. 11.1982

2307

For the preparation of ion exchangers with Am i η η ph о s T> h ^ ns Чig group η

Application s field of the invention

Ion exchangers with aminophosphones and urea groups find application in the enrichment and separation of metal ions, especially of heavy metal ions. Accordingly, hydrometallurgy represents an important field of application. Due to the pronounced selectivity of these ion exchangers, they continue to be used for the purification of industrial waste water, the metal ions being bound and Value metals can be recovered.

Characteristic of the known technical solutions

Various processes are known for the preparation of ion exchangers with aminophosphonic acids. The most important processes are characterized in that crosslinked polymers carrying amino groups are reacted with formaldehyde and yhosphorous acid. These production methods are e.g. in SU patents 481.6-8 and 487.091 and in the publication by V.S. Soldatov et al. in Zumal prikladnoi ohimii, Wr. 1 (1978), pp. 80-84. Significant disadvantage of this method

UROI 1982 * 0460 ??

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However, ййР the reactivity of the phosphorus acid strength Ъеі the processes described is not Groh enough to -.υ achieve complete reaction with the amino group and the formaldehyde. The capacities of the finished exchangers for :: etallions therefore do not reach the size required for many application purposes. Thus, in SU-PS 481.628,

2+

For example, for Cu-in with

maximum 4.05 roval / g indicated.

2+

For example, for Cu-in at a pH k capacities of

Object of the invention

^'7 iel the invention is a process for the preparation of ion exchange resins with aminophosphonic acid groups, which have a higher capacity for metal ions, particularly heavy metal ions fflr.

Explanation of the essence of the invention

The object of the invention was to provide a favorable process for animal production of ion exchangers which by reacting "acromolekfilen with amino groups with suitable substances such ion exchangers sohaffen, which have a particularly high capacity for T'etallionen.

Surprisingly, it has now been found that dan AminophosphonsMuregruT) -oeη carrying ion exchanger with high Ionenaustauschkat) azit4t for metals obtained when carrying amino groups polymers with a mixture of formaldehyde and derivatives of phosphorus! S4ure treated with or without phosphorous acid. Particularly suitable derivatives of the phosphorous acid have proved to be halogenated alkanol esters. Of these, in turn, the bis- and tris-2-Chlorethy! Ester are particularly favorable in their reaction behavior. The reactivity of these derivatives is so grop, since ^ ffftirt the implementation of the cross-linked amino group-bearing macromolecules at temperatures up to 100 ⁰ C and reaction times of 5-10 hours to complete conversions.

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f terras rather de rwei se satisfies the addition of 5 wt ¹ ^ haloalkyl, based on the total amount of haloalkyl esters and phosphorous acid in the reaction mixtures with phosphorous acid in order to obtain a final product with high capacity for heavy metal ions, ttberrasehend was also the fact in that the proportion of haloalkyl esters in the range from 5 to 100% by weight and consequently the proportion of phosphorous acid from 95 to 0% by weight can be varied without adversely changing the metal capacity. If the reaction is carried out without phosphorous acid when using formaldehyde and haloalkyl esters of phosphorous acid, it is necessary to treat the product initially formed in the reaction with dilute acids or alkalis to convert all haloalkyl ester groups into the aminophosphonic acid groups. Temperatures are sufficient to 100 ⁰ C for the whole course of this reaction being preferably carried out in the temperature range of 50 to 8O ⁰ C.

When working with mixtures of phosphorous acid and its haloalkyl esters, it is also desirable to carry out an acid or alkali treatment if the proportion of haloalkyl esters exceeds 30% by weight. For this reaction, preference is given to using glacial or sulfuric acid or soda or potassium hydroxide in the concentration range of from 3 to 5% by weight. As crosslinked, amino-bearing polymers know all known sohwaoh basic anion exchangers are used for this reaction, which have as functional groups primary and / or secondary amino groups. In known manner, these exchangers may be of gel-like or porous structure. Examples are sohwaoh baseohe Anionenaustausoher on the basis of styrene-divinylbenzene Copolyraerisaten, of crosslinked aoryl or Methaorylsäurederivaten and based on crosslinked! Called polyvinyl chloride. The so-called basic ion exchangers can be used both in the

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As well as in the salt form ί4τ the reaction can be used to Austausohern with Aminophosphonsäuregruppen. Preferably, however, the salt form and thereby the Cl "" - form is used. The! Formaldehyde is best used as an aqueous solution (formalin) in the usual range of concentration from 30 to 40 °.

The reaction of the sohwaoh baseohen exchanger with formaldehyde and the 2-haloethyl esters of the phosphorous acid or with the mixtures of acid and ⁷ Sster is preferably carried out that the exchanger initially exchanged in water-swollen state with formaldehyde and then the ester is added. In some cases the addition of a small amount of concentrated hydrochloric acid proved to be beneficial. When tris-halogens are used, it is expedient to heat them in advance in a separate reaction vessel in the presence of water to temperatures of at most 1000 ° C., the amount of water, based on 1 mole of ester, being 0.5 to 2 mol should. The gemisoh is then brewed with the suspension of exchanger and formaldehyde for the reaction. If mixtures of tris-P-halide of thy le te te and an aqueous T.fisung of phosphorous acid are used for the reaction, then a preliminary heating of the ester in the presence of water should only be carried out if the Proportion of the ester in the Reaktionsmisohung greater than 50 wt .- ^ is.

The following examples are intended to further illustrate the invention without, however, limiting it thereto.

Embodiment Example 1

A porous sohwaoh basic anion exchanger, which in a known Tise by suspension polymerization of 95 parts of styrene and 5 parts of divinylbenzene in the presence of an inert, chloromethylation of the polymer and subsequent

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Reaction with urotropin is induced by treatment with HCl in the Cl ~ form.

Kennwe rte the Austausohers

Total weight capacity: 4.5 meq / g dry exchanger

in the Cl "" form

Water content * 67.6 %

To 100 ml of water swollen exchanger is added 100 g of 35 formalin. Parallel to this, 270 g of tris-2-Chlorethylphosphit (content 80 $) and 20 ml of distilled water in a second GEFs "heated for 1 hour at 100 ⁰ C and then added to the suspension exchanger formalin. The mixture is heated now to 8O ⁰ C and allowed stir the suspension for 8 hours at this temperature.

Thereafter, the fiferohuß is aspirated from the reaction solution, the exchanger treated for 5 hours with 400 ml 5 #iger ITaCH at 6O ⁰ C and then washed neutral with distilled water. There are obtained 120 ml exchangers with Aminophosphons turegruppen.

Characteristics of the Austurchhers

Total weight capacity: 8.1 meq / g dry exchanger

in the H ⁺ form

Water content: 48.4 %

Exposure Capacities to metal ions during loading with 0.05 m solutions in the Batoh process

Capacity pH (mval / g dry exchanger in the H ⁺ -form)

2.0 3.1 2.5 2.6

4.0 6.5 6.0 5.4

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Example 2

A porous sohwaoh basic anion exchanger is prepared in a known manner by suspension polymerization of 95 parts of aorylsurate and 5 parts of divinylbenzene in the presence of an inert agent and subsequent reaction of the polymer with propylenediamine. By treatment with HCl, the exchanger is converted into the Cl "- form.

Characteristics of Austurchhers

Total weight capacity: 4.6 meq / g dry exchanger

in the Cl ~ form

Water content: 66.5 %

To 100 ml of water-swollen ion exchanger is added 50 ml of 15% HCl, 110 g of formalin (35%) and 190 g of 2-chloroethyl phosphite. Danaoh, the suspension is heated to 100 ⁰ C for 8 hours. The ffbersohuß to KeaktionslHsung is filtered off with suction and the exchanger with 400 ml of 5% NaOH 5 hours at 80 ⁰ C heated. It is sparingly neutralized with distilled water. Ss 114 ml ion exchangers are obtained with aminophosphonic acid groups.

Characteristics of the exchanger

Total Water Capacity: 8.7 meq / g dry exchanger

in the H ⁺ form

Water content: 49.8 H>

Cu ²⁺ capacity at loading with 0.05 M solution in the Batoh process

pH 2 * 3.5 meq / g dry exchanger

in the H ⁺ form

nH 4 x 6.8 meq / g dry exchanger

in the H ⁺ form

2307

Example 3

100 ml of water-swollen exchanger in the Cl 2 -Po form prepared as described in Example 1 are mixed with 100 g of 35% formalin, 18 g of tris-2-chloroethyl phosphite and 165 g of phosholic acid ( 50 $ strength by weight w ^ flrige solution) and heated for 8 hours at 100 ⁰ C. the ffoerschuß to Reaktionslflsung is suction filtered and washed with distilled water of the exchangers neutral ·

115 ml of ion exchangers with aminophosphonic acid groups are obtained.

Characteristics of Austurchhers

Total weight capacity: 8.0 meq / g dry exchanger

Water content:

Cu ²⁺ capacity at loading with 0.05 mB? 5 solution in the Batoh method:

pH '2: pH 4 t

in the H form 47.3 #

3.1 meq / g dry exchanger in the H ⁺ form

6.4 meq / g dry exchanger in the H ⁺ form

Claims (3)

- 8 - 2307 Invention claim 1. A process for the preparation of ion exchangers with Aminophosphonsäuregruppen, daduroh characterized in that weak baseohe Anionenaustbekher with primary and / or secondary amino groups with a Gemisoh of formaldehyde and a haloalkyl ester of phosphorous acid with or without the addition of phosphorous acid at temperatures of 50 to 100 ⁰ C. be implemented. 2. The method according to item 1, daduroh in that the proportion of the haloalkyl ester of Fhosphorigen acid 5 to 100 wt .- $, based on the total amount of haloalkyl esters of phosphorous acid and phosphorous acid, is. 3. The method according to item 1, daduroh characterized in that is used as the haloalkyl esters of phosphorous acid bis-2-chloroethyl phosphite. Process according to item 1, characterized daduroh, is used as the haloalkyl ester of the phosphorous acid tris-2 chloroethylnhosphite.