EP1530596A1

EP1530596A1 - Method for producing monodisperse gel-type ion exchangers

Info

Publication number: EP1530596A1
Application number: EP03793680A
Authority: EP
Inventors: Wolfgang Podszun; Reinhold Klipper; Dmitry Chernyshov
Original assignee: Bayer Chemicals AG
Current assignee: Lanxess Deutschland GmbH
Priority date: 2002-08-16
Filing date: 2003-08-02
Publication date: 2005-05-18
Also published as: CN1688617A; JP2005535778A; CN100349927C; US20060199892A1; WO2004022611A1; AU2003255363A1; NO20051271L; DE10237601A1

Abstract

The invention relates to a method for producing monodisperse gel-type ion exchangers with a particle size of between 5 and 500 µm. Said exchangers are obtained as follows: a) production of a non-cross linked monodisperse seed polymer with a particle size of between 0.5 and 20 µm by the radically initiated polymerisation of monoethylenically unsaturated compounds in the presence of a non-aqueous solvent, b) addition of an active monomer mixture containing styrene as the feed for said seed polymer; the monomer mixture is then left to swell into the seed and the product is polymerised at high temperature; optionally the steps involving the addition of the monomer mixture, the swelling process and polymerisation are repeated once or several times, the monomer mixture during the final addition containing between 2 and 50 wt. % of a cross linking agent and c) functionalisation of the polymer using a sulphonating agent either into cation exchangers, or by amidomethylation with a subsequent hydrolysis, or chloromethylation with subsequent amination into anion exchangers.

Description

Process for the production of monodisperse gel-shaped ion exchangers

The invention relates to a method for producing monodisperse gel-like

5 ion exchangers with a particle size of 5 - 500 μm.

Ion exchangers are generally obtained by functionalizing crosslinked styrene bead polymers. For example, to produce cation exchangers, covalently bonded sulfonic acid groups are obtained by reacting aromatic units of the polymer skeleton with a sulfonating agent, e.g. Produces sulfuric acid.

Anion exchangers contain covalently bound amino groups or ammonium groups, which can be generated, for example, by chloromethylation and subsequent amination.

15 Recently, ion exchangers have been used with the most uniform particle size possible

- hereinafter referred to as "monodisperse" - has become increasingly important because, in many applications, economic advantages can be achieved from monodisperse ion exchangers due to the more favorable hydrodynamic properties of an exchange bed. Monodisperse ion exchangers can be

.0 nationalization of monodisperse polymer beads can be obtained.

One of the possibilities for producing monodisperse bead polymers is the so-called seed / feed process, after which a monodisperse bead polymer ("seed") is swollen in the monomer and this is then polymerized. Seed / feed processes ^» 5 are described, for example, in EP 0 098 130 B1 and EP 0 101 943 B1.

EP-A 826 704 discloses a seed / feed process in which microencapsulated crosslinked bead polymer is used as the seed.

10 A problem with the known methods for producing monodisperse ion exchangers by seed-feed technology is the provision of monodisperse Persian seeds. A frequently used method is the fractionation of bead polymers with conventional, ie broad particle size distribution. A disadvantage of this process is that the yield of the desired target fraction during screening decreases sharply with increasing monodispersity.

Spraying techniques can be used to produce monodisperse bead polymers in a targeted manner. Atomization processes suitable for ion exchangers are described, for example, in EP 0 046 535 B1 and EP 0 051 210 B2. A common characteristic of these atomization processes is their very high technical expenditure. The atomization processes usually lead to ion exchangers with a

Particle size from 500 - 1200 μm. Ion exchangers with smaller particle sizes cannot be produced or can only be produced with significantly increased effort.

EP 0 448 391 B1 discloses a process for producing polymer particles of uniform particle size in the range from 1 to 50 μm. In this process, an emulsion polymer with particle sizes of preferably 0.05 to 0.5 μm is used as the seed.

US Pat. No. 6,239,224 B1 describes a seed-feed process for producing expandable polystyrene beads with a particle size of at least 200 μm.

Cross-linked monodisperse bead polymers with a particle size of 1-30 μm are known from EP 0 288 006 B1. These bead polymers are obtained by a seed-feed process in which cross-linked seed particles are used.

Although numerous methods and processes for the production of monodisperse bead polymers or monodisperse ion exchangers have been described above, there is as yet no practical method for the targeted production of monodisperse ion exchangers with a particle size of 5 to 500 μm. The present invention relates to a process for the production of monodisperse gel-shaped ion exchangers with a particle size of 5 to 500 μm, which is characterized in that

a) an uncrosslinked monodisperse seed polymer with a particle size of

0.5 to 20 μm generated by radical-initiated polymerization of monoethylenically unsaturated compounds in the presence of a non-aqueous solvent,

b) to this seed polymer an activated styrene-containing monomer mixture as

Add feed, the monomer mixture swells into the seeds and polymerizes at elevated temperature, the steps of adding monomer mixture, swelling and polymerizing, if necessary, repeated one or more times, the monomer mixture containing 2 to 50 wt .-% crosslinking agent in the last addition and

c) the resulting polymer is converted into ion exchangers by functionalization.

The particle size of the ion exchanger according to the invention is 5 to 500 μm, preferably 10 to 400 μm, particularly preferably 20 to 300 μm. Conventional methods such as sieve analysis or image analysis are suitable for determining the average particle size and the particle size distribution. The ratio of the 90% value (0 (90) and the 10% value (0 (10) of the volume distribution is formed as a measure of the width of the particle size distribution of the ion exchangers according to the invention. The 90% value (0 (90) gives the diameter below which 90% of the particles fall below. Correspondingly, 10% of the particles fall below the diameter of the 10% value (0 (10). Monodisperse particle size distributions in the sense of the invention mean 0 (90) / 0 (10) <1.5, preferably 0 (90) 70 (10) <1.25. Monoethylenically unsaturated compounds are used to produce the uncrosslinked seed polymer according to process step a), no multiply ethylenically unsaturated compounds or crosslinking agents being used.

Monoethylenically unsaturated compounds for the purposes of the present invention are: styrene, vinyl toluene, alpha-methyl styrene, chlorostyrene, esters of acrylic acid or methacrylic acid such as methyl methacrylate, ethyl methacrylate, ethyl acrylate, isopropyl methacrylate, butyl acrylate, bulyl methacrylate, hexyl methacrylate, 2-ethylhexyl acrylate, ethyl Dodecyl methacrylate, stearyl methacrylate, or iso-bornyl methacrylate. Styrene, methyl acrylate or butyl acrylate are preferably used. Mixtures of different monoethylenically unsaturated compounds are also very suitable.

In the preparation of the uncrosslinked seed polymer, the abovementioned monoethylenically unsaturated compound (s) are used in the presence of a nonaqueous

Polymerized solvent using an initiator.

Non-aqueous solvents suitable according to the invention are dioxane, acetone, acetonitrile, dimethylformamide or alcohols. Alcohols, in particular methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol and tert-butanol, are preferred. Mixtures of different solvents, in particular mixtures of different alcohols, are also very suitable. The alcohols can optionally also contain up to 50% by weight of water, preferably up to 25% by weight of water. When using solvent mixtures, non-polar solvents, in particular hydrocarbons, such as hexane, heptane and toluene, can also be used

Proportions up to 50 wt .-% can be used.

The ratio of monoethylenically unsaturated compounds to solvents is 1: 2 to 1:30, preferably 1: 3 to 1:15. The seed polymer is preferably prepared in the presence of a high molecular weight dispersant dissolved in the solvent.

Natural and synthetic macromolecular compounds are suitable as high molecular weight dispersants. Examples are cellulose derivatives, such as methyl cellulose, ethyl cellulose, hydroxypropyl cellulose, polyvinyl acetate, partially saponified polyvinyl acetate, polyvinyl pyrrolidone, copolymers of vinyl pyrrolidone and vinyl acetate, and copolymers of styrene and maleic anhydride. According to the invention, polyvinylpyrrolidone is preferred. The content of high molecular weight dispersant is 0.1 to 20% by weight, preferably 0.2 to 10% by weight, based on the solvent.

In addition to the dispersants, ionic and non-ionic surfactants can also be used. Suitable surfactants are e.g. Sodium sulfosuccinic acid, methyltricaprylammonium chloride or ethoxylated nonylphenols. Ethoxylated nonylphenols having 4 to 20 ethylene oxide units are preferred. The surfactants can be used in amounts of 0.1 to 2% by weight, based on the solvent.

Initiators suitable for the production of the seed polymer are compounds which form free radicals when the temperature rises. Examples include: peroxy compounds such as dibenzoyl peroxide, dilauryl peroxide, bis (p-chlorobenzoyl) peroxide, dicyclohexylperoxydicarbonate or tert-amylperoxy-2-ethylhexane, and further azo compounds such as 2,2'-azobis (isobutyronitrile) or 2,2'- Azobis (2-methylisobutyronitrile). If the solvent contains a share of water, is also

Sodium or potassium peroxydisulfate is suitable as an initiator.

Also highly suitable are aliphatic ^"peroxy esters. Examples are tert-butyl peroxyacetate, tert-butyl peroxyisobutyrate, tert-butyl peroxypivalate, tert-Butylper- oxyoctoat, tert-butyl peroxy-2-ethylhexanonate, t-butyl peroxyneodecanoate, tert-

Amylperoxypivalate, tert.-amylperoxyoctoate, tert.-amylperoxy-2-ethylhexanonate, tert-amylperoxyneodecanoate, 2,5-bis (2-ethylhexanoylperoxy) -2,5-dimethylhexane, 2,5-dipivaloyl-2,5-dimethylhexane, 2,5-bis (2-neodecanoylperoxy) -2,5-dimethyl - hexane, di-tert-butyl peroxyazelate or di-tert-amylperoxyazelate.

The initiators are generally used in amounts of 0.05 to 6.0% by weight, preferably 0.2 to 4.0% by weight, based on the monoethylenically unsaturated compounds).

Inhibitors soluble in the solvent can be used. Examples of suitable inhibitors are phenolic compounds such as hydroquinone, hydroquinone monomethyl ether, resorcinol, pyrocatechol, tert-butyl pyrocatechol, condensation products from phenols with aldehydes. Other organic inhibitors are nitrogen-containing compounds such as Diethyl hydroxylamine and isopropyl hydroxylamine. Resorcinol is preferred as an inhibitor. The concentration of the rhodium is 0.01 to 5% by weight, preferably 0.1 to 2% by weight, based on the monoethylenically unsaturated compounds.

The polymerization temperature depends on the decomposition temperature of the initiator and on the boiling point of the solvent and is typically in the range from 50 to 150 ° C., preferably 60 to 120 ° C. It is beneficial in the

Polymerize the boiling point of the solvent with constant stirring with a grid stirrer. Low stirring speeds are used. For example, in the case of 4 liter laboratory reactors, the stirring speed of a grid stirrer is 50 to 250 rpm, preferably 100 to 150 (rpm = revolutions per minute).

The polymerization time is generally several hours, e.g. 2 to 30 hours.

The seed polymers produced in process step a) according to the invention are highly monodisperse and have particle sizes of 0.5 to 20 μm, preferably 2 to 15 μm. It was found in the context of the present work that the particle size can be influenced, among other things, by the choice of the solvent. For example, higher alcohols such as n-propanol, iso-propanol, n-butanol, iso-butanol and tert-butanol provide larger particles than methanol. The particle size can be shifted to lower values by a proportion of water or hexane in the solvent. The addition of toluene increases the particle size.

The seed polymer can be isolated by conventional methods, such as sedimentation, centrifugation or filtration. To separate the dispersing agent, it is washed with alcohol and / or water and dried.

In process step b), the seed polymer is mixed with an activated styrene-containing monomer mixture as a feed. In the present context, styrene-containing means that the mixture contains 50 to 99.9, preferably 80 to 99.9% by weight of styrene. The remaining components of the mixture are

Comonomer, crosslinker and initiator for the activation.

Suitable comonomers are compounds which can be copolymerized with styrene, e.g. Methyl methacrylate, ethyl methacrylate, ethyl acrylate, hydroxyethyl methacrylate or acrylonitrile.

Crosslinkers are compounds with two or more polymerizable olefinically unsaturated double bonds in the molecule. Examples include divinyl benzene, allyl methacrylate, ethylene glycol dimethacrylate, butanediol dimethacrylate, trimethylolpropane triacrylate, butanediol divinyl ether and octadiene. Divinylbenzene is preferred. The divinylbenzene can be used in commercially available quality, which in addition to the isomers of divinylbenzene also contains ethylvinylbenzene.

The initiators for process step b) are the radical formers described in process step a). The initiators are generally in Amounts of 0.1 to 4.0 wt .-%, preferably 0.5 to 2.5 wt .-% based on the monomer mixture used. Of course, mixtures of the aforementioned radical formers can also be used, for example mixtures of initiators with different decomposition temperatures.

The weight ratio of seed polymer to monomer mixture is 1: 1 to 1: 1000, preferably 1: 2 to 1: 100, particularly preferably 1: 3 to 1:30.

The monomer mixture is generally added to the seed polymer in such a way that an aqueous dispersion of the seed polymer is used

Emulsion of the monomer mixture is added. Finely divided emulsions with average particle sizes of 1 to 10 μm, which are produced using rotor-stator mixers or mixed jet nozzles using an emulsifying agent, such as e.g. Isoctyl sulfosuccinic acid sodium salt can be prepared.

The monomer mixture can be added at temperatures below the decomposition temperature of the initiator, for example at room temperature. It is advantageous to stir the emulsion containing the monomer mixture with stirring for a longer period, e.g. meter in within 0.25 to 3 hours. After the emulsion has been added completely, stirring is continued until the monomer has completely penetrated the seed particles. This usually takes 0.5 to 2 hours and can be easily checked by observing a sample with light microscopy. The amounts of water used in the production of the seed polymer suspension and monomer mixture emulsion are large

Limits not critical. Generally 10 to 50% suspensions or emulsions are used.

The mixture of seed polymer, monomer mixture and water obtained is mixed with at least one dispersing aid, natural and synthetic water-soluble polymers, such as gelatin, starch, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polymethacrylic acid or copolymers of (meth) acrylic acid or (meth) acrylic acid esters are suitable. Cellulose derivatives, in particular cellulose esters or cellulose ethers, such as carboxymethyl cellulose or hydroxyethyl cellulose, are also very suitable. The amount of dispersant used is generally 0.05 to 1%, preferably 0.1 to 0.5%, based on the water phase.

The water phase can also contain a buffer system which adjusts the pH of the water phase to a value between 12 and 3, preferably between 10 and 4. Particularly suitable buffer systems contain phosphate, acetate,

Citrate or borate salts.

It may be advantageous to use an inhibitor dissolved in the aqueous phase. Both inorganic and organic substances can be considered as inhibitors. Examples of inorganic inhibitors are nitrogen compounds such as hydroxylamine, hydrazine, sodium nitrite and potassium nitrite. Examples of organic inhibitors are phenolic compounds such as hydroquinone, hydroquinone monomethyl ether, resorcinol, pyrocatechol, tert-butyl pyrocatechol, condensation products from phenols with aldehydes. Other organic inhibitors are nitrogen-containing compounds such as Diethylhydroxylamine or isopropylhydroxylamine. According to the invention, resorcinol is preferred as an inhibitor. The concentration of the inhibitor is 5-1000, preferably 10-500, particularly preferably 20-250 ppm, based on the aqueous phase.

By increasing the temperature to the decomposition temperature of the initiator, in general

The polymerization of the monomer mixture swollen in the seed particles is initiated at 60-130 ° C. The polymerization takes several hours, e.g. 3 to 10 hours.

In a particular embodiment of the present invention, the monomer mixture is added over a longer period of 1 to 6 hours at Temperature at which at least one of the initiators used is active. In general, temperatures of 60-130 ° C., preferably 60-95 ° C., are used in this procedure.

The feed step, i.e. Addition of monomer mixture, swelling and polymerizing can be done one or more times, e.g. Repeat 2 to 10 times. This means that the product produced in a previous feed step is used as a seed polymer for the subsequent feed step. Due to the repeated repetition of the feed steps, monodisperse seed polymers with particle sizes of 0.5 to 20 μm are ultimately monodisperse polymers

Particle sizes of up to 500 μm accessible. The enlargement factor results from the weight ratio of seed polymer to monomer mixture. This is again 1: 1 to 1: 1000, preferably 1: 2 to 1: 100, particularly preferably 1: 3 to 1:30.

In the context of the present invention, it was found that the crosslinker content in the monomer mixture is important for the high monodispersity of the ion exchangers obtained. If the feed steps are repeated several times, crosslinkers are only used in the last feed step. The amount of crosslinker in the last feed step is 2 to 50% by weight, preferably 3 to 20% by weight, in each case based on the activated styrene-containing monomer mixture added.

After the polymerization, the polymer formed can be processed using the usual methods, e.g. isolated by filtration or decanting and, if necessary, dried once or several times and sieved if desired.

The polymer from process step b) can be converted to the ion exchanger according to process step c) by known processes. Cation exchangers are manufactured by sulfonation. Suitable sulfonating agents are sulfuric acid, sulfur trioxide and chlorosulfonic acid. Is preferred

Sulfuric acid with a concentration of 90-100%, particularly preferably 96- 99% used. The temperature during the sulfonation is generally 50-200 ° C., preferably 90-130 ° C. If desired, a swelling agent such as chlorobenzene, dichloroethane, dichloropropane or methylene chloride can be used in the sulfonation.

During the sulfonation, the reaction mixture is stirred. Different types of stirrers, such as blade, anchor, grid or turbine stirrers, can be used. It has been shown that a radially demanding double turbine stirrer is particularly well suited.

After sulfonation, the reaction mixture of sulfomerization product and residual acid is cooled to room temperature and first diluted with decreasing concentrations of sulfuric acids and then with water.

If desired, the cation exchanger obtained according to the invention can be

Form for cleaning with deionized water at temperatures of 70 - 145 ° C, preferably from 105 - 130 ° C are treated.

For many applications it is advantageous to convert the cation exchanger from the acid form to the sodium form. This transhipment takes place with a sodium hydroxide solution

Concentration of 10-60%, preferably 40-50%. In the context of the present work, it was determined that the temperature is important during transhipment. It has been shown that at charge temperatures of 60-120 ° C, preferably 75-100 ° C, there are no defects on the ion exchange balls and the purity is particularly high.

Anion exchangers can be obtained, for example, by amidoalkylation of the polymer from process step b) and subsequent hydrolysis. N-hydroxymethylphthalimide and bis (phthalimidomethyl) ether are particularly suitable as Ajxiidoalkylierungsmittel. In this reaction, aminomethylated crosslinked polystyrene bead polymerizates are obtained which are weakly basic anion exchangers.

These weakly basic anion exchangers can be converted into medium-based ones by reaction with formic acid / formaldehyde after the LeuckartAVallach reaction

Anion exchangers or quaternization with alkyl halides such as chloromethane or ethyl chloride can be converted into strongly basic anion exchangers.

Anion exchangers can also be prepared by haloalkylation of the polymer from process step b) and subsequent amination. A preferred haloalkylating agent is chloromethyl methyl ether. Weakly basic anion exchangers can be obtained from the haloalkylated polymers by reaction with a secondary amine, such as dimethylamine. The reaction of the haloalkylated polymers with tertiary amines, such as

Trimethylamine, dimethylisopropylamine or dimethylaminoethanol strongly basic anion exchangers.

Chelate resins can also be produced in a simple manner from the polymers according to the invention. For example, the reaction of a haloalkylated polymer with iminodiacetic acid gives chelate resins of the iminodiacetic acid type.

The ion exchangers obtained by the process according to the invention are notable for high monodispersity, particularly high stability and purity.

Appropriate functionalization gives the monodisperse gel-like cation exchangers according to the invention or monodisperse gel-like anion exchangers with particle sizes of 5 to 500 μm. The invention therefore relates to monodisperse gel-like anion exchangers or monodisperse gel-like cation exchangers with a particle size of 5 to 500 μm, obtainable by

a) producing an uncrosslinked monodisperse seed polymer with a

Particle size from 0.5 to 20 μm by free-radically initiated polymerization of monoethylenically unsaturated compounds in the presence of a non-aqueous solvent with a particle size from 0.5 to 20 μm,

b) adding an active styrene-containing monomer mixture as a feed to this

Seed polymer, allowing the monomer mixture to swell into the seeds and polymerizing at elevated temperature, optionally repeating the steps of adding the monomer mixture once or several times, allowing the polymer mixture to swell and polymerizing, the monomer mixture containing 2 to 50% by weight of crosslinking agent in the last addition and

c) Functionalization by means of a sulfonating agent either to cation exchangers or by amidomethylation with subsequent hydrolysis or by chloromethylation with subsequent amination to anion exchangers.

The anion exchangers produced according to the invention are used

for removing anions from aqueous or organic solutions and their vapors

for removing anions from condensates

for removing paint particles from aqueous or organic solutions and their vapors for decolorization and desalination of glucose solutions, whey, thin gelatin broths, fruit juices, fruit must and sugars, preferably of mono- or disaccharides, in particular cane sugar, beet sugar solutions, fructose solutions, for example in the sugar industry, dairies, starch and in the pharmaceutical industry,

for removing organic components from aqueous solutions, for example humic acids from surface water.

Furthermore, the anion exchangers according to the invention can be used for

Purification and treatment of water in the chemical and electronics industries, especially for the production of ultrapure water.

Furthermore, the anion exchangers according to the invention can be used in combination with gel-like and / or macroporous cation exchangers for the complete demineralization of aqueous solutions and / or condensates, in particular in the sugar industry.

There are a multitude of different applications for the cation exchangers produced according to the invention. They are also used, for example, in drinking water treatment, in the production of ultrapure water (necessary for microchip production for the computer industry), for the chromatographic separation of glucose and fructose and as catalysts for various chemical reactions (such as bisphenol-A -Manufacture from phenol and acetone). For most of these applications, it is desirable that the cation exchangers perform their intended functions without releasing contaminants that may arise from their manufacture or that arise from polymer degradation during use. The presence of refinements in the water flowing away from the cation exchanger is noticeable in that the conductivity and / or the organic carbon content (TOC content) of the

Water are elevated. The cation exchangers according to the invention are also extremely suitable for the complete demineralization of water. No increased conductivity is observed even after the desalination plants have been standing for a long time. Even if the structure-property correlation of the cation exchangers according to the invention is not known in all details, it is likely that the favorable leaching properties can be attributed to the special network structure.

The present invention therefore relates to the use of the cation exchangers according to the invention

for the removal of cations, color particles or organic components from aqueous or organic solutions and condensates, e.g. Process or turbine condensates,

for softening by neutral exchange of aqueous or organic solutions and condensates, e.g. Process or turbine condensates,

for cleaning and processing water from the chemical industry, electronics industry and from power plants,

for the complete desalination of aqueous solutions and / or condensates, characterized in that they are used in combination with gel-like and / or macroporous anion exchangers,

for decolorization and desalination of whey, thin gelatin broths, fruit juices, fruit musts and aqueous solutions of sugar.

The present invention therefore also relates to Process for the complete demineralization of aqueous solutions and or condensates, such as process or turbine condensates, characterized in that, according to the invention, monodisperse cation exchangers are used in combination with heterodisperse or monodisperse, gel-like and / or macroporous anion exchangers,

Combinations of monodisperse cation exchangers produced according to the invention with heterodisperse or monodisperse, gel-like and / or macroporous anion exchangers for the complete desalination of aqueous solutions and / or condensates, such as e.g. Process or turbine condensates,

Process for the purification and processing of water from the chemical, electronics and power plants, characterized in that the monodisperse cation exchanger according to the invention is used,

Methods for removing cations, color particles or organic components from aqueous or organic solutions and condensates, e.g. Process or turbine condensates, characterized in that the monodisperse cation exchangers according to the invention are used,

Process for softening by neutral exchange of aqueous or organic solutions and condensates, e.g. Process or turbine condensates, characterized in that the monodisperse cation exchangers according to the invention are used,

Process for decolorization and desalination of moles, thin gelatin broths. Fruit juices, fruit musts and aqueous solutions of sugars in the sugar, starch or pharmaceutical industries or dairies, characterized in that the monodisperse cation exchangers produced according to the invention are used. Test Methods

Determination of the stability of cation exchangers due to alkali fall.

In 50 ml 45 wt. % sodium hydroxide solution, 2 ml of sulfonated copolymer in the H form are introduced at room temperature with stirring. The suspension is left to stand overnight. Then a representative amount of sample is taken. 100 beads are observed under the microscope. The number of perfect, undamaged pearls is determined from this.

Determination of the amount of basic aminomethyl groups in an aminomethylated, crosslinked polystyrene bead polymer

100 ml of the aminomethylated, crosslinked bead polymer are shaken in a tamping volumeter under water and then transferred to a glass column. 1000 ml of 2 wt. Are added over the resin in 1 hour and 40 minutes. %, aqueous sodium hydroxide solution filtered. Then, fully deionized water is filtered through the resin until 100 ml of the eluate flowing out of the resin mixed with phenol phthalein is used in the titration with 0.1 normal hydrochloric acid not more than 0.05 ml.

50 ml of the resin are mixed in a glass beaker with 50 ml of deionized water and 100 ml of 1N hydrochloric acid. The suspension is stirred for 30 minutes at room temperature and then rinsed into a column. The liquid is drained. A further 100 ml of 1N hydrochloric acid are filtered through the resin in 20 minutes. Then 200 ml of methanol are filtered through the resin. All eluates are collected and combined and titrated with 1 N aqueous sodium hydroxide solution against methyl orange as an indicator. The amount of ammomethyl groups in 1 liter of the aminomethylated crosslinked polystyrene bead polymer is calculated using the following formula: (200 - V) x 20 = mol of ammomethyl groups per liter of resin

Determination of the degree of substitution of the aromatic nuclei in the cross-linked

Polystyrene bead polymer by ammomethyl groups

The amount of ammomethyl groups in the total amount of resin is determined by the above method.

The molar amount of aromatic nuclei in the amount of bead polymer is calculated by dividing the amount of bead polymer by the molecular weight.

180 g of bead polymer are used to prepare 568 ml of aminomethylated crosslinked polystyrene bead polymer with 1.38 mol of ammomethyl groups.

568 ml of aminomethylated crosslinked polystyrene bead polymer contain 1.69 mol of aromatic nuclei. Each aromatic nucleus then contains 1.38 / 1.69 = 0.82 mol of ammomethyl groups.

The degree of substitution of the aromatic nuclei in the crosslinked polystyrene bead polymer is then 0.82.

Number of perfect pearls after production

100 beads are viewed under the microscope. The number of pearls that have cracks or chips is determined. The number of perfect pearls results from the difference between the number of damaged pearls and 100. Determination of the stability of the resin after the roller test

The bead polymer to be tested is distributed in a uniform layer thickness between two plastic wipes. The cloths are placed on a firm, horizontally attached support and subjected to 20 working cycles in a rolling apparatus. On

The work cycle consists of rolling back and forth. After rolling, the number of undamaged beads is determined on representative samples of 100 beads each by counting under the microscope.

Swelling rod ility test

25 ml of anion exchanger in the chloride form are introduced into a column. 4 wt .-% aqueous sodium hydroxide solution, fully demineralized water, 6 wt .-% hydrochloric acid and again fully demineralized water are added to the column, the sodium hydroxide solution and the hydrochloric acid flowing through the resin from above and the demineralized water from below through the Resin is pumped. The treatment is timed via a control unit. A work cycle lasts for you. 20 working cycles are carried out. At the end of the working cycles, 100 beads are counted out of the resin pattern. The number of perfect pearls that are not damaged by cracks or chips is determined.

Determination of the amount of weakly and strongly basic groups in anion exchangers

100 ml of anion exchanger in a glass column in 1 hour and 40 minutes with 1000 ml of 2 wt .-% sodium hydroxide solution. The resin is then washed with deionized water to remove the excess sodium hydroxide solution. Determination of the NaCl number

50 ml of the exchanged in the free base form and washed neutral are placed in a column and treated with 950 ml of 2.5 wt .-% aqueous sodium chloride solution. The drain is collected, made up to 1 liter with deionized water and 50 ml of this are titrated with 0.1N (= 0.1 normal hydrochloric acid) hydrochloric acid. The resin is washed with deionized water.

Used ml 0.1 n hydrochloric acid x 4/100 = NaCl number in mol / liter resin.

Determination of the NaNOy number

Then 950 ml of 2.5% by weight sodium nitrate solution are filtered through. The drain is made up to 1,000 ml with deionized water. An aliquot of this - 10 ml - is removed and its chloride content is analyzed by titration with mercury nitrate solution.

Used ml of Hg (NO ₃ ) solution x factor / 17.75 = NaNO ₃ number in mol / liter of resin.

Determination of the HO number

The resin is washed with deionized water and rinsed in a beaker. 100 ml of 1N hydrochloric acid are added and the mixture is left to stand for 30 minutes. The entire suspension is rinsed into a glass column. A further 100 ml of hydrochloric acid are filtered through the resin. The resin is washed with methanol. The drain is made up to 1,000 ml with deionized water. 50 ml of this are titrated with 1N sodium hydroxide solution.

(20 - 1 ml of sodium hydroxide solution consumed) / 5 = HO number in mol / liter of resin. The amount of strongly basic groups is equal to the sum of the NaN03 ~ number and HO number.

The amount of weakly basic groups is equal to the HO number.

Determination of the amount of chelating groups in the chelating resin - determination of the total capacity

100 ml of chelate resin to be examined are poured into a glass column and mixed with 3 wt. % hydrochloric acid eluted in 1.5 hours. Then it is washed with deionized water until the process is neutral.

50 ml of chelate resin to be examined are poured into a glass column and treated with 0.1 normal sodium hydroxide solution. The effluent is collected in a 250 ml glass flask and the entire amount is titrated against methyl orange with 1 normal hydrochloric acid.

1 normal sodium hydroxide solution is added until 250 ml of drain have a consumption of 24.5 to 25 ml of 1 normal hydrochloric acid. After the test has been completed, the volume of the exchanger in the Na form is determined.

Total capacity (TK) = 8 X - 25 - ∑ V) - 3 in mol / liter exchanger

X = number of the drain fraction ∑ V = total consumption in ml of 1 normal hydrochloric acid for the titration of the drains. Examples

example 1

a) Preparation of a seed polymer

2325 g of n-butanol, 75 g of toluene, 180 g of polyvinylpyrrolidone (Luviskol K30) are stirred for 20 minutes in a 4 1 three-necked flask which has been flushed with a nitrogen stream of 20 l / h, a homogeneous solution being obtained. There are then 300 g of styrene, 3.75 g with further stirring at 150 rpm (revolutions per minute)

Sulfosuccinic acid isooctyl ester sodium salt and 4.5 g resorcinol added and heated to 80 ° C. A solution of 3 g of azo-diisobutyric acid and 117 g of n-butanol, heated to 40 ° C., is added all at once into the mixture and the mixture is kept at 80 ° C. for 20 hours. The reaction mixture is then cooled to room temperature, and the resulting polymer is isolated by centrifugation, twice with

Methanol and washed twice with water. In this way, 950 g of an aqueous dispersion with a solids content of 20% by weight are obtained. The particle size is 4.5 μm, 0 (90) / 0 (10) is 1.08.

bl) first feed step

300 g of styrene, 9.24 g of 75% by weight dibenzoyl peroxide, 500 g of water, 3.62 g of ethoxylated nonylphenol (Arkopal N060), 0.52 g of sulfosuccinic acid, sodium octyl ester and 2 g of 3.3 ', 3 "5,5'5" -hexa-tert-butyl-α, α', α "- (mesitylene-2,4,6-triyl) tri-p-cresol (inhibitor Irganoxl330) with an ultrurax (3 min, rate 13500,) a finely divided emulsion-I was generated.

A solution of 5 g of methylhydroxyethyl cellulose in 2300 g of deionized water and 200 g of aqueous dispersion from a) is introduced into a 4 1 three-necked flask which has been flushed with a nitrogen stream of 20 l / h. At room temperature, the finely divided emulsion-I is stirred with constant pumped speed. The mixture is then left at room temperature for a further 3 hours at room temperature and then heated to 80 ° C. for 9 hours. The reaction mixture is then cooled to room temperature, the resulting polymer is isolated by centrifugation and washed twice with water and dispersed in water. In this way, 1500 g of an aqueous dispersion with a solids content of 20% by weight are obtained. The particle size is 8.8 μm, 0 (90) 70 (10) is 1.10.

b2) second feed step

In a plastic container, 288 g of styrene, 12 g of 80% by weight divinylbenzene, 9.24 g of dibenzoyl peroxide, 500 g of water, 3.62 g of ethoxylated nonylphenol (Arkopal N060), 0.52 g of sodium sulfosuccinate and 2 g of 3 , 3 ', 3 "5,5'5" -hexa-tert-butyl-alpha,', "- (mesitylene-2,4,6-triyl) tri-p-cresol (inhibitor Irganoxl330) with an ultraturax (3 min, rate 13500,) produces a fine emulsion.

c)

A solution of 5 g of methylhydroxyethyl cellulose in 2300 g of deionized water and 200 g of aqueous dispersion from B1) is introduced into a 4 1 three-necked flask which has been flushed with a nitrogen stream of 20 l / h. At room temperature, the finely divided emulsion from b2) is pumped in at a constant rate over the course of 3 hours. The mixture is then left at room temperature for a further 3 hours at room temperature and then heated to 80 ° C. for 9 hours.

The reaction mixture is then cooled to room temperature, the polymer formed is isolated by centrifugation and washed three times with water and dried at 80.degree. In this way, 312 g of bead polymer with a particle size of 16 μm are obtained. 0 (9O) / 0 (10) is 1.15. d) Preparation of a cation exchanger

900 ml of 97.32% by weight sulfuric acid are placed in a 2 1 four-necked flask and heated to 100.degree. In 4 hours, a total of 200 g of dry copolymer from c) are introduced in 10 portions with stirring. Then more

Stirred at 100 ° C for 4 hours. After cooling, the suspension is transferred to a glass column. Sulfuric acids of decreasing concentrations, starting with 90% by weight, finally pure water are filtered through the column from above. 1090 ml of cation exchanger are obtained in the H form. The particle size is 22 μm, 0 (90) / 0 (10) is 1.15.

Example 2

a) Preparation of a seed polymer

According to Example 1a), a monodisperse seed polymer with a particle size of 4.5 μm is produced.

bl) first feed step

300 g of styrene, 9.24 g of 75% by weight dibenzoyl peroxide, 500 g of water, 3.62 g of ethoxylated nonylphenol (Arkopal N060), 0.52 g of sulfosuccinic acid isooctyl ester and a salt of 2 g of 3.3 'are used in a plastic container. , 3 "5,5'5" -hexa-tert-butyl-α, α ', α "- (mesirylene-2,4,6-triyl) tri-p-cresol (inhibitor Irganoxl330) with an ultra-turax ( 3 min, rate 13500,) produces a fine emulsion-I.

A solution of 5 g of methylhydroxyethyl cellulose in 2300 g of deionized water and 200 g of aqueous dispersion from a) is introduced into a 4 1 three-necked flask which has been flushed with a nitrogen stream of 20 l / h. At room temperature with stirring, the finely divided emulsion-I pumped in at constant speed within 3 hours. The mixture is then left at room temperature for a further 3 hours at room temperature and then heated to 80 ° C. for 9 hours. The reaction mixture is then cooled to room temperature, the resulting polymer is isolated by centrifugation and washed twice with water and in

Water dispersed. In this way, 1500 g of an aqueous dispersion with a solids content of 20% by weight are obtained. The particle size is 8.5 μm, 0 (90) / 0 (10) is 1.10.

b2) second feed step

Using 813.38 g of emulsion I and 200 g of the aqueous dispersion from bl), a second feed step is carried out while maintaining the conditions of the first feed step. The resulting bead polymer is washed and dried. 308 g of bead polymer having a particle size of

15.5 μm. 0 (90) 70 (10) is 1.15.

b3) third feed step

A third feed step is carried out using 813.38 g of emulsion I and 40 g of bead polymer from b2) while maintaining the conditions of the second feed step. The resulting bead polymer is washed and dried. 315 g of bead polymer with a particle size of 26 μm are obtained. 0 (90) 70 (10) is 1.15.

b4) fourth feed step

Using 813.38 g of emulsion I and 40 g of bead polymer from b3), a fourth feed step is carried out while maintaining the conditions of the third feed step. The resulting bead polymer is washed and dries. 318 g of bead polymer with a particle size of 49 μm are obtained. 0 (9O) / 0 (10) is 1.18.

b5) fifth feed step

Using 813.38 g of Emulsion-II from 270 g styrene, 30 g 80% by weight divinylbenzene, 9.24 g dibenzoyl peroxide, 500 g water, 3.62 g ethoxylated nonylphenol (Arkopal N060), 0.52 g sulfosuccinic acid sodium salt and 2 g 3,3 ', 3 "5,5'5" -hexa-tert-butyl-alpha, α', α "- (mesitylene-2,4,6-τriyl) tri-p- cresol (inhibitor Irganoxl330) and 40 g of bead polymer from b4), a fifth feed step is carried out while maintaining the conditions of the fourth feed step. The bead polymer obtained is washed and dried. 325 g of bead polymer with a particle size of 99 μm are obtained ) / 0 (10) is 1.2.

e) Production of a cation exchanger

900 ml of 98% strength by weight sulfuric acid are placed in a 2 1 four-necked flask at room temperature. 200 g of dry copolymer from b5) are metered in with stirring over the course of 15 minutes. The mixture is then heated to 120 ° C. in 3 h and stirred at 120 ° C. for a further 4 hours. After cooling, the suspension is transferred to a glass column. Sulfuric acids of decreasing concentrations, starting with 80% by weight, finally pure water are filtered through the column from above. 950 ml of cation exchanger are obtained in the H form. The particle size is 150 μm, 0 (90) / 0 (10) is 1.15.

Example 3

Production of a weakly basic and strongly basic anion exchanger

Apparatus:

I Four-necked flask, water separator, thermometer, dropping funnel, pH electrode, pH-controlled pump, cooler

3 a) N-methylolphthalimide

At room temperature, 853.6 g of 1,2 dichloroethane, 279.2 g of phthalimide and

201.1 g of formalm (28.9% by weight of formaldehyde) are initially introduced. The mixture is heated to the reflux temperature. When this temperature is reached, a pH-controlled pump by means of 50 wt. % sodium hydroxide solution, the pH is adjusted to 5.5-6. 30 minutes after a cloudy solution has formed, a sample is taken and the composition is analyzed by thin layer chromatography.

N-methylolphthalimide: 95.0% phthalimide: 3% phthalic acid: 2%

3b) bis (phthalimidomethyl) ether

After the water present in the reaction mixture has been completely removed, 20.5 g of sulfuric acid monohydrate are metered in. A clear solution is available after the dosing rank has ended. That which is formed in the subsequent implementation

Water is being removed. A sample is then taken and the composition is analyzed by thin-layer chromatography.

N-methylolphthalimide: 2.6% phthalimide: 5.5%

Phthalic acid: 1.6% bis (phthalimidomethyl) ether: 90.3% 3 c) N-acetoxymethylphthalimide

The suspension of bis (phthalimidomethyl) ether obtained is heated to 60 ° C. Then 96.9 g of acetic anhydride are metered in over 5 minutes. After the dosing has been completed, a clear solution is available. The mixture is stirred at 60 ° C. for 15 minutes, then heated to 80 ° C. and stirred at this temperature for 10 minutes. A sample is then taken and the composition is analyzed by thin layer chromatography.

N-methylolphthalimide: 2% phthalimide: 4.5% phthalic acid: 2%

Bis (phthalimidomethyl) ether: 0.2% N-acetoxmethylphthalimide: 91.3%

3d) condensation of the N-acetoxmethylphthalimide with bead polymer

The solution of N-acetoxmethylphthalimide obtained is cooled to 45-50 ° C. Then 180 g of bead polymer from Example 2b5 are metered in in 30 minutes. It will

Stirred at 45-50 ° C for 30 minutes. Then 71.9 g of sulfuric acid monohydrate are metered in within one hour. The mixture is heated to 80 ° C. in 45 minutes and stirred at this temperature for 7 hours. After cooling, the bead polymer is transferred to a glass frit filter. The condensation broth is suctioned off. The bead polymer is washed several times with methanol. The bead polymer is then 20 wt. In 1820 ml. % aqueous sodium chloride solution entered. The suspension is heated to reflux temperature and residual 1,2-dichloroethane and methanol are distilled off. The bead polymer obtained is washed with water after cooling. Resin yield: 650 ml 3e) treatment of the phthalimidomethylated bead polymer with ammonia solution

650 ml of phthalimidomethylated bead polymer and 592 g of ammonia solution are placed in the flask at room temperature, heated to 90 ° C. and for 4 hours

Temperature stirred. After cooling, the resin is washed with water.

Resin yield: 635 ml Elemental analysis composition:

Carbon: 76.1% by weight

Hydrogen: 5.1% by weight

Nitrogen: 5.0% by weight

Oxygen: 13.8% by weight

3 f) implementation of the phthalimidomethylated bead polymer with sodium hydroxide solution for the aminomethylated bead polymer preparation of the weakly basic anion exchanger

610 ml resin from 3e) and 281 g 50 wt. % sodium hydroxide solution are placed in an autoclave at room temperature and heated to 180 ° C. with stirring within 2 hours. The mixture is stirred at 180 ° C for 6 hours. After cooling, the resin is washed with water.

Resin yield: 550 ml

Carbon: 81.7% by weight Hydrogen: 8.1% by weight Nitrogen: 7.7% by weight Oxygen: 2.5% by weight HCl number: 2.43 mol / 1 substitution: 0.82

Stability: Original condition: 99% whole pearls

After roll test: 97% whole pearls After swelling stability: 98% whole pearls

3g) implementation (quaternization) of the aminomethylated bead polymer with chloromethane to give a strongly basic anion exchanger

320 ml of aminomethylated polymer beads, 538 ml of demineralized water and 179.7 g of 50% by weight. % sodium hydroxide solution are placed in an autoclave at room temperature. Then 144 g of chloromethane are metered into the autoclave. The mixture is heated to 40 ° C. and stirred at this temperature for 16 hours. The stirring speed is 400 rpm.

After cooling, the resin is washed neutral on a sieve and transferred to a glass column. 2000 ml of 3% by weight aqueous hydrochloric acid are filtered through from above.

Resin yield: 530 ml

HCl number: 0.08 mol / l NaCl number: 1.35 mol / 1

NaNO ₃ number: 0.96 mol / 1

Stability:

Original condition: 99% whole pearls. After rolling test: 98% whole pearls

After swelling stability: 98% whole pearls Example 4

Production of a chelate resin with iminodiacetic acid groups

500 ml of a weakly basic anion exchanger prepared according to Example 3 f) are suspended in 800 ml of deionized water. 339.8 g of sodium monochloroacetate are metered into the suspension in 30 minutes. The mixture is stirred for a further 30 minutes at room temperature. Then the pH of the suspension with 20 wt. % sodium hydroxide solution adjusted to pH 10. Within

The suspension is then heated to 80 ° C. for 2 hours. Then the mixture is stirred for a further 10 hours at this temperature. The pH is adjusted during this time by dosing 20 wt. % sodium hydroxide solution kept at 10.

After cooling, the resin is filtered off and washed free of chloride with deionized water.

Resin yield: 928 ml

Total resin capacity: 2.53 mol / 1

Claims

Patentansprfiche

1. A method for producing monodisperse gel-shaped ion exchangers with a particle size of 5 to 500 microns, which is characterized in that

a) an uncrosslinked monodisperse seed polymer (with a particle size of 0.5 to 20 μm) is produced by radical-initiated polymerization of monoethylenically unsaturated compounds in the presence of a non-aqueous solvent,

b) an activated styrene-containing monomer mixture is added as feed to this seed polymer, which allows the monomer mixture to swell into the seed and polymerizes at elevated temperature, the steps of adding the monomer mixture, allowing it to swell and polymerizing are repeated one or more times, where appropriate, the monomer mixture being added 2 to 4 in the last addition Contains 50% by weight crosslinker and

c) the resulting polymer is converted into ion exchangers by functionalization.

2. The method according to claim 1, characterized in that cation exchangers are prepared by sulfonation in process step c).

3. The method according spoke 1, characterized in that anion exchangers are prepared by amidomethylation with subsequent hydrolysis in process step c).

4. Monodisperse gel-shaped ion exchanger with a particle size of 5 to

500 μm available through a) producing an uncrosslinked monodisperse seed polymer having a particle size of 0.5 to 20 μm by radical-initiated polymerization of monoethylenically unsaturated compounds in the presence of a non-aqueous solvent,

b) adding an active styrene-containing monomer mixture as feed to this seed polymer, allowing the monomer mixture to swell into the seed and polymerizing at elevated temperature, optionally repeating the steps of adding one or more times

Monomer mixture, swelling and polymerizing, the monomer mixture containing 2 to 50 wt .-% crosslinker at the last addition and

c) Functionalization using either a sulfonating agent

Cation exchangers or by amidomethylation with subsequent hydrolysis to anion exchangers or chloromethylation with subsequent amination.