SU1168567A1 - Method of obtaining sorbents - Google Patents

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The invention relates to the production of synthetic ion exchange resins of practically any functionality and neutral sorbents for the purification, separation and concentration of various substances from aqueous organic and gaseous media for chromatographic analysis, organic catalysis, etc. A known method for producing ion exchangers and neutral sorbents by radical copolymerization of mono- and divilyl monomers, followed by the introduction of ionogenic groups by polymer polymorphisms L. The lack of these materials is not high enough mechanical and osmotic strength. This is due to the fact that the reaction of copolymerization of mono - and divinyl monomers is characterized by a pronounced gel effect and proceeds with a peaked heat release. This leads to an increase in the temperature inside the sample to 140 ° C, while the desired temperature of the coolant will not exceed 80 ° C. In order to obtain sorbents in the form of spherical granules, the copolymerization is usually carried out by the suspension method, one of the main advantages of which is the relatively easy removal of the heat that is copolymerized. Due to the fact that the resulting copolymer has a relatively large grain diameter (0.25-1.5 mm) and is with a poor heat conductor, the suspension medium does not completely dissipate the heat produced. Significant local heating has a large effect on the rate of peroxide decomposition and the rate of copolymerization, and, consequently, on the structure of the copolymer, forming stresses and defects in it, which lead to the fact that the sorbents obtained on their basis have insufficiently high mechanical and osmotic strengths . The closest to the invention is a method of producing ion exchangers by copolymerizing mono and divinyl monomers in the presence of organic solvents that mix well with the initial monomers and have a Bbmie boiling point of copolymerization, not participating in the copolymerization reaction, remaining in the system , and removed from the final product by steam distillation, vacuum drying or extraction. In this way, sorbents of macroporous structure 21 are obtained. I However, expanding the range of ion exchange applications poses new, increased requirements for sorbents. The mechanical strength of sorbents becomes one of the main properties that determine the economics of their use in continuous water treatment processes, organic catalysis, pulp processes in hydrometallurgy, in periodic ion exchange processes with increasing flow rates of solutions, etc. The purpose of the invention is to increase the mechanical and osmotic strength of ion exchange and neutral sorbents polymerization. This goal is achieved by the fact that according to the method for producing sorbents by radical copolymerization of one or several mono- and divinyl monomers in the presence of an organic solvent, followed by the introduction of ionic groups, a low-boiling organic solvent is used as an organic solvent since 1-30 C below the temperature of the beginning of polymerization in the amount of 1-25 wt.% from the mass of monomers The copolymerization is carried out in pri-; the absence of a blowing agent. The proposed method is as follows. Suspension copolymerization of mono- and divinyl monomers is carried out in the presence of radical type initiators in a solvent medium, the boiling point of which is close, but does not exceed the gelation temperature (the beginning of polymerization), creates a local removal of exothermic heat at the moment of its peak-like release due to the heat consumption for evaporation. this solvent. Solvent vapors are condensed in a reverse fridge and the solvent is re-rotated into the reaction system, reheated by exothermic heat to the boiling point, evaporates again, carrying off some of the heat, etc. Repeated evaporation of the solvent permits complete removal of the peaked heat. Consequently, the copolymerization reaction proceeds under milder conditions and the copolymer is free from the drawbacks of the similar copolymers obtained by known methods. Ionogenic groups are introduced into the copolymer by the usual polypereological transformations, for example, by sulfonation, phosphorylation, saponification, chloromethylation followed by amination, etc. As monomers, aliphatic, aromatic and heterocyclic mono-divinyl compounds or mixtures thereof, such as styrene, vinyl pyridines, unsaturated carboxylic acid esters of acrylonitrile, aminovinyl pyridines, divinyl benzene, diisopropyl benzene, divinyl pyridine, etc., are used. Example 1. A mixture consisting of 50 g of styrene, 4.16 g of 50% divinylbenzene (DVB), 0.27 g of benzoyl peroxide and 7.8 g of chloroform is loaded into 90 ml of 1% starch solution at 60 ° C The duration of copolymerization is 8 hours at 60-90 C. The resulting copolymer is separated from the mother liquor, washed with demineralized water and dried to a residual moisture content of not more than 0.05%. The copolymer yield is 52.9 g (98% of the theoretical) 197.8 ml of monochlorodimethyl ether and 26.45 g of zinc chloride are added to the copolymer (52.9 g) and the chloromethylation reaction is carried out at 4550 ° C for 6 hours. The resulting chloromethylated copolymer (CMS) is separated from the mother liquor, washed with methylal or methanol until the neutral reaction over methyl orange and aminated with ethylenediamine. For this purpose, CMS is filled with a solution of 10.5 ml of ethylenediamine in 105 ml of methylal and left to swell for 1 h, then add 280 , 8 ml of ethylenediamine and incubated for 8 hours at 40 ° C. After cooling The anion exchanger is separated from the mother liquor and washed with water until neutral with phenolphthalein. The total exchange capacity (POE) under static conditions is 0.1 NHC 6.5 mg eq / g or 2.5 meq / ml, under static conditions. specific volume of 2.6 ml / g, osmotic stability of 97%. Example 2. A mixture consisting of 31 g of acrylonitrile, 1.8 g of 50% DVB, 0.3 g of benzoyl peroxide, 2.9 ml of dichloromethylene is loaded into 85 ml of a 1.5% starch solution containing 28 g of salt, at. The copolymerization is carried out at 60 ° C for 9 hours. The copolymer obtained is separated from the mother liquor and washed with hot water. The output of the copolymer of 30.0 g (91.5% of theoretical). The copolymer is hydrolyzed with 120 ml of a 30% aqueous solution of sodium hydroxide for 16 hours at 90-96 ° C. The resulting carboxyl cation exchanger has a POU of 0.1 H. NaOH 8.5mgq / g or 4.4 mgeq / ml, specific volume 1.9 ml / g, osmotic stability 98X. Example 3, A mixture consisting of 31 g of acrylonitrile, 1.8 g of 50% DVB, 0.49 g of dinitriloazoisobutyric acid, 4.8 g of chloroform and 4.9 g of a pore-forming agent dichloroethane is loaded into 6 mp 1.5 % starch solution containing 21 g of sodium chloride at 50 ° C. The duration of copolymerization is 15 hours at 50-60 C. The resulting copolymer is separated from the mother liquor and treated with live steam. The output of the copolymer of 28.5 g (90% of theoretical). The copolymer is animated with dimethylpropylene diamine. The 29.5 copolymer is poured with a mixture of 29.5 ml of water, 0.3 g of zinc chloride and 0.3 g of 96-98% sulfuric acid, and stirred for 1 hour at room temperature. 118 ml of dimethylpropylene diamine are then added and aminated for 10 hours at. SOU 0.1 n. HC1 3.9 mg eq / g or 1.45 MGEQ / ML, specific volume 27 ml / g osmotic stability 96%. Example 4. A mixture consisting of 50 g of 2.5 methyl vinyl pyridine, 8.6 g of 50% DVB, 0.44 g of benzoyl peroxide, 0.44 g of tert-butylperbenzoate and 12.5 ml of n-hexane are loaded into 150 ml 1% starch solution containing 57 g of salt, at 50 ° C. The copolymerization is carried out at 60-90 ° C for 6 hours. The granules are separated from the mother liquor and washed with water, 5% hydrochloric acid solution and again with water. The anion exchanger obtained has a POU of 0.1 N.HC1 of 5.6 mg eq / g, osmotic stability of 98%, and mechanical strength of 97%. Example 5. A mixture consisting of 51 g of styrene, 18 g of 50% DVB, 0.6 g of benzoyl peroxide, 9.6 g of chloroform and 69 ml of BR-1 gasoline is loaded into 148 ml of 1% starch solution at 60 C. The duration of copolymerization is 15 hours at 60-90 0. The copolymer is separated from the mother liquor, treated with live steam. Yield 65.9 g (98% of theoretical). The copolymer is sulphurized with 96% sulfuric acid, poured with 27 ml of dichloroethane and left to swell for 1 hour. Then 251 ml of 96% sulfuric acid is added. The duration of the sulfonation is 8 hours at 85-90 ° C. The sulfonation is carried out with simultaneous distillation of dichloroethane. The cooled cation exchanger is washed with sulfuric acid of decreasing concentration, then with water. POU 0.1 H.NaOH 4.7 mg eq / g or 1.3 mgEq / ml. Equilibrium static exchange capacity of 0.1 n. CaC 4.3 MGEQ / ML, specific volume 3.6 ml / g, osmotic stability 99%. Example 6. A mixture consisting of 30 g of aminovinipridine, 2.4 g of divinylpyridine, 0.5 gDAC and 4.5 ml of n-pentane is loaded into 95 ml of 1% starch solution containing 37 g of sodium chloride at 40c. The copolymerization is carried out at 60-95 0 for 9 hours, the anion exchanger is separated from the mother liquor, washed with hot water. POU at 0.1 N.H.SN1 805 mEq / g, specific volume 3.8 ml / g, mechanical strength 95%. Example 7, 74 g of the anion exchanger obtained in Example 1, containing primary and secondary amino groups, are poured with 500 ml of 5% formic acid and allowed to swell for 1 hour. Excess acid is separated and the resin is treated with a mixture of 100 ml 85 % formic acid and 30 g of 35% formalin. The reaction time is 4 hours at 90-120s. The anion exchanger is separated from the mother liquor, and rinsed with water. The resulting anion exchanger contains only tertiary amino groups and has a full exchange capacity of 0.1 nN.SH 5.9 mg eq / gi 2.3 mEq / ml, specific volume 2.5 ml / g, osmotic stability. Example 8. Mixture The bulk of 50 g of styrene, 9.1 g of 50% DVB, 0.6 g of benzoyl peroxide, 4.6 ml of chloroform and 54 ml of BLH gasoline are loaded into 150 ml of 1% starch solution at. The copolymerization lasts 15 hours at 60-95 C. The copolymer is separated from the mother liquor, treated with live steam, dried to a residual moisture content of not more than 0.05%, and chloromethylated in Example 1. Amintation of CMS swollen in methylal is carried out with a ratio of 61 g CMS - 190 ml of diethylenetriamine for 6 hours at 50-95 with distillation of methylal during the amification process. The anion exchanger is separated from the mother liquor and washed. POU at 0.1 N.H.SN 6.9 mEq / g or 1.95 mEq / ml, specific volume 3.5 mg / g, osmotic stability 99%, mechanical strength 97%. Example 9. 64 g of CMS prepared according to Example 1 is poured with a mixture of 10 ml of diethylenetriamine and 65 ml of methylal and allowed to swell for 1 hour. Then, with cooling, 180 ml of diethylenetriamine are added and aminated at 50-95 ° C for 7 hours with distillation of methylal in the amination process. The anion exchanger is separated from the mother liquor and washed. POU 0.1 HNS1 7.9 mg eq / g or 2.7 mg.Eq / ml, specific volume 2.9 ml / g, osmotic stability 97%. EXAMPLE 10 A mixture consisting of 50 g of styrene, 144 g of 50% DVB, 0.5 ml of n-hexane, 215 ml of BR-1 gasoline is loaded into 450 ml of 1% solution. starch at 50 C. The duration of copolymerization is 15 hours at 60-95 s. The copolymer is separated from the mother liquor and treated with live steam. The obtained neutral sorbentpolysorb has a specific surface 325 with a total pore volume of 0.93 cm / g, a mechanical strength of 98%. Example 11. A mixture consisting of 35 g of styrene, 2.8 g of diisopropenyl benzene, 0.6 g of benzoyl peroxide and 5.5 g of chloroform are loaded into 60 ml of a 1% aqueous solution of starch at 50 s. The duration of the copolymerization of 9 h at 70-105 ° C. The resulting copolymer is separated from the mother liquor, flushed with hot water and dried to a residual moisture content of not more than 0.05%. The chlorine copolymer is methylated in Example 1, then aminated with a 25% aqueous solution of trimethylamine for 6 hours at 38 ° C.

SOE pa 0.1 N.NS1 5,4 mEq / g or 1.2 mgeq / ml. Exchange capacity 0.1 n. NaCl - 5.2 mg.eq./g or 1.1 mg.eq./ml. The specific volume of 4.6 ml / osmotic stability is 98%.

Example 12. A mixture consisting of 85 g of styrene, 4.7 g of 50% DVB, 0.8 g of acrylonitrnl, 4.9 dichloromethylene, 0.41 g of benzoyl peroxide is loaded into 80 ml of a 1% solution of the collapse small at 50 C. Duration of copolymerization for 6 hours at 60-95 C. The resulting copolymer is separated from the mother liquor, washed with hot water and dried to a residual moisture content of not more than 0.05%. The output of the copolymer of 39.2 g (98% of theoretical). The copolymer swells in 17.4 ml of dichloroethane over 30 minutes, then sulphurized with 96% sulfuric acid to 98 ml in those. 8 hours at 80-90 ° C under dichloroethane distillation conditions. The cation exchanger is washed with decreasing concentration of sulfuric acid, then with water.

POI 0.1 H.NaOH 5.2 mEq / g or 2.0 mg eq / ml, exchange capacity 0.1 N.CaC 4.9 mg eq / g or 1.9 mg.eq. / ml, specific volume

2.6 ml / g, osmotic stability 98%.

Example 13. 60 g of the macroporous copolymer obtained in Example 10 are poured with 220 ml of monochloromethyl ether with 30 g of zinc chloride dissolved in it in 15 g of chloromethylation for 15 hours at 50 ° C. Then the chloromethylated copolymer is separated from the mother liquor, washed with methylal until neutral with methyl-orange. 240 ml of a 22% aqueous solution of trimethylamine are added to the copolymer swollen in methylal. The amination time is 8 hours at 88 ° C. The finished anion exchanger is washed with water, then with 5% hydrochloric acid solution and again with water.

SOE at 0.1 N. CH1 1.2 mg-eq / g or 0.4 mg.eq./g, specific volume 2.74 ml / g, osmotic stability 99%.

Comparison of the osmotic strength of ion exchangers, obtained by the proposed method and known as presented in the table.

The tests showed that the osmotic stability of ionites obtained by the proposed method was significantly better than that of nonites obtained by a known method. The proposed method of producing ion exchangers can be carried out without altering the technological scheme of production of polymerization ion exchangers.

Claims (2)

1. METHOD FOR PRODUCING SORBENTS by copolymerizing one or more mono- and divicyl monomers in the presence of an organic solvent followed by the introduction of ionic groups, characterized in that, in order to increase the osmotic and mechanical strength of the sorbents, a low-boiling organic solvent with t .kip. 1-30 ° C below the temperature of the onset of polymerization in an amount of 1-25 wt. X by weight of the monomers. 2. The method according to π. 1, a t h l and A u _to u and d with me that the copolymerization is carried out in the presence of £ blowing agent. SU „,, 1168567