Phosphorus-contained polycondensation type ion-exchange resins.
Today ion-exchange polymers, thanks to the valuable properties, have found wide application in hydrometallurgy, water preparation, in clearing of various industrial and waste waters of chemical manufactures. In many regions of Uzbekistan, especially, in Karakalpakstan, water has the raised rigidity of 10-12 mg-ekv/l at norm of 2.5-7 mg-ekv/l (Pulatov, Tursunov, and Nazirova, 2006). Besides, ion-exchange division of ions of some metals, such as molybdenum-reny and others, is a significant problem to hydrometallurgical manufactures. The annual requirement of domestic economic industries in ion-exchange polymers makes about fifteen thousand tons. Nowaday ion-exchange polymers are imported into Uzbekistan from the CIS countries, and it considerably affects cost of manufactured products. Therefore, there is an expediency to create the production of ion-exchangers with orientation to a local source of raw materials.
The basic possibility of this problem solution is working out new or updating of existing ion-exchange polymers production technologies. Rational use of accessible substances and secondary material resources will allow organizing manufacturing of ion-exchange polymers based on stable raw-material base.
Chemical, agricultural, cotton scrape and other industries provide a real raw-material base to production of ion-exchange polymers. There are accessible products, in particular in productions JSC "Navoiazot", JSC "Maxam-Chirchik", cotton scrape factories, etc. These industries produce large-tonnage products which represent perspective raw materials for production of ion-exchange polymers with good indicators of operational properties. Besides, processing of the above-stated raw materials in ion-exchange polymers production meets requirements of ecological efficiency as assume applying low-waste technologies.
Polymers production using the derivatives of furan appears interesting, as the country possesses huge stocks of vegetative raw materials, including large-tonnage wastes of cotton processing industry. These raw materials are one of sources of receiving some chemical compounds, including furfural and its derivatives (Sherbakov, 1962). High polyfunctionality of furfural caused its use for producing of polymers possessing universal chemical firmness, increased heat and thermal resistance (Tursunov and Nazirova, 1985a).
We were the first received and investigated new phosphate cation-exchange resins, nitrogen-phosphorus containing ion-exchange resins using chemical transformation of benzyl bromide-furfural polymers (Tursunov and Nazirova, 1985b; 1985c). Validity and perspectives of a choice of furfural as a raw source for creation ion-exchange polymers is caused by presence in its structure of the heterocyclic groupings necessary for receiving ion exchangers with the prescribed properties, namely, thermal and chemical stability, mechanical durability and radiation stability.
Synthesis ion exchangers by chemical transformation of products of polycondensation of furfural and halogenbenzyls
Reaction of polycondensation benzyl bromide with furfural was studied by chemical and physical methods. Reaction course of polycondensation was controlled on concentration change of furfural and bromine through certain time intervals. In parallel removed IR-spectra of reactionary weight from the beginning of reaction to gel formation. The study has shown that polycondensation of furfural with benzyl bromide, basically, proceeds at the expense of interaction of mobile atoms of hydrogen of benzyl bromide aromatic kernel in orto- and pair-positions; and partially for the account bromomethyl groups with aldehyde group of furfural. The quantity of bromine in an initial stage of reaction made 26% and decreased by the reaction end to 10-12%. Reduction of the bromine concentration may also be related to the volatility of the initial monomer. IR-spectroscopic examination of initial substances, reaction mass and polymer confirms this point of view. The synthesized polymer was hardened to constant weight, and then it was phosphorylated (Tursunov and Nazirova, 1978).
Phosphorylation of polymers on a basis of furfural and benzyl bromide
In search of a convenient method of carrying out of reaction of synthesized polymer phosphorylation, reaction was organized in the environment of three-chloride phosphorus in the presence of aluminium chloride at 50, 60, 700[degrees]C. Dependences of degree of polymer transformation on time and temperature were removed to study a change in the phosphorylation process speed. Kinetics of reactions was registered by defining the maintenance of the entered phosphorus and static exchange capacity of end-product. Reaction of polymeranalogous transformations shows the heterogeneous process presented in this case by interaction bromomethyl group of polymer with three-chloride phosphorus. The general speed of heterogeneous reaction in the investigated case can be defined by diffusion of three-chloride phosphorus or actually speed of one of stages of chemical reaction. Kinetic dependences of reaction speed on time-lg (1-A) =k[tau] for film and A=k ([tau]) for gel kinetics (A - degree of phosphorylation of polymer during time) were excluded (Tursunov, 2009).
In the analysis of the received kinetic curves it was established that kinetic area, characteristic for chemical reaction, is observed at A=0.15-0.3. Changes of constants of phosphorylation reaction speed in dependence on site (A=0.1-0.3, [tau] =60 minutes) temperature correspond to the Arrhenius equation (Table 1).
Energy of chemical reaction activation was calculated on a tangent of a straight line slope based on dependence of -lgK on 1/T. Limiting influence of gel kinetics was considered also using linear dependence in coordinates A=f ([square root of ([tau])]) at A=0.1-0.3. The magnitude of diffusion activation energy was defined from dependence - lg [D.sub.ef] = f(1/T).
On the basis of the received experimental data it is possible to draw a conclusion that polymer phosphorylation reaction on a basis furfural and benzyl bromide proceeds with sufficiently high degree of transformation; speed of process phosphorylation is defined in an initial stage (A=0.3) and limited by kinetic area of chemical reaction. Further process of transformation degree increasing is characterized by penetration of three-chloride phosphorus deep into polymer grains, i.e. diffusion in granules of polymer (Table 1) becomes a limiting stage of process. On the basis of experimental data for reaction phosphorylation polymer on the basis of benzyl bromide and furfural the following optimum conditions are accepted: [tau] =7.0-7.5 hours, T=700[degrees]C, molar parity of benzyl bromide to furfural 2:1. Table 2 shows the basic properties of received cationites.
Except phosphorylation the synthesized polymer on a basis furfural and benzyl bromide, we also conducted reaction of its amination for the purpose of receiving anion-exchanger containing high-basic groups. Polymer was aminated by trimethylamine. Concentration influence of trimethylamine, temperatures, durations of reaction and dependence of properties anion-exchange resin on a parity of benzyl bromide and furfural in a reactionary mix (Tursunov, Zajnutdinova, and Nazirova, 1999) were studied.
Polymer amination was made after its preliminary swelling in organic solvents. Studying of influence of reaction temperature to polymer transformation degree was made at 20, 30, 40[degrees]C. The obtained data testify that optimal amination temperature is 20[degrees]C. Research of influence of trimethylamine quantity on size of anion-exchange resin exchange capacity showed that the maximum degree of amination of polymer is reached at 4 multiple surplus of amine.
Duration of amination varied in the range of 2-6 hours. 6 hours were accepted as optimal time of amination. Speed of amination substantially depends on degree of crosslinking polymer: the more strongly polymer is sewed, the more slowly process of diffusion proceeds and longer time for reaction end is required.
Research shows that with furfural concentration increase in a reactionary mix the size of exchange capacity and swelling capacity of anion-exchange resin go down. At using 1 mole furfural to 1.5 moles benzyl bromide the size of exchange capacity reaches 3.5 mg-ekv/g. The preliminary results shows possibility of anion-exchange resins synthesis using polymer amination on a basis furfural and benzyl bromide.
Synthesis of nitrogen-phosphorus contained ion-exchange resins
As a polymeric matrix for introduction of phosphate groups we used anion-exchanger, synthesized by polycondensation polyethylenepolyamine (PEPA), furfural and benzyl bromide. Table 3 shows properties of the anion-exchanger. Phosphorylation of anion-exchange resin was made by three-chloride phosphorus in the presence of waterless chloride aluminium (Turobjonov et al., 2005). Studying of dependence of anion-exchange resin phosphorylation degree on process duration, at molar parity of three-chloride phosphorus and three-chloride aluminium 4:2, showed that optimal time of phosphorylation of anion-exchange resin is 6-7 h. Thus the polymer contains 9% of P corresponding to exchange capacity of 3 mg-ekv/g of a caustic sodium solution. Spectral examination showed that in a spectrum of phosphorylated anion-exchange resin there were strips in the field of 750 [sm.sup.-1] corresponding to P-C-communication, and 2250-2230 [sm.sup.-1] corresponding to P(0)[(OH).sub.2] group. Deformation fluctuations in the field of 825-805 [sm.sup.-1] are connected with 1,2,3,4-replacement in benzene ring. Strips of absorption in the field of 900, 650, 1150 [sm.sup.-1] are connected with fluctuations of primary and secondary amines which are identical to the same strips of absorption in a spectrum non-phosphorylated anion-exchanger. Valence vibrations of -C-N= amine linkage are shown in the field of 1220-1230 [sm.sup.-1]. However, presence in the same area of absorption strips of P[0.sub.2][H.sub.2] groups complicates their interpretation. On the basis of data of the element analysis, alkalimetric titration, the IRspectroscopy, etc. we can assert that synthesized polymeric ampholyte contains in the structure except amino groups also phosphate groups. The basic physical and chemical properties of the received polymeric ampholyte are shown in the Table 2.
To find specific objects of practical application there were studied sorptive and operational properties of the received ion-exchange resins.
Research of properties in phosphorus-containing ion-exchange resins
Cationites with phosphorus-containing groups represent a class of the selective sorbents capable to display both of ion-exchange and complexing properties. The presence of three functional groups, two acid hydroxyls and phosphoryl oxygen is characteristic to phosphorus-containing cation-exchange resins. In subacid and alkaline environments, at absence of complexing metals for these cation-exchange resins, usual dissociation with an exchange of cations is typical. Speed of exchange reactions for one-and bivalent ions on phosphate cation-exchange resins is less than on sulfonic acid and on carboxylated cation-exchange resins; i.e. speed of reaction falls from strong - to weak dissociate: S[O.sub.3]H>PO[(OH).sub.2]>COOH. Data in the Table 2 testify that the size of exchange capacity makes 6 mg-ekv/g on ions [Na.sup.+] from alkaline solutions, and 0.8 mg-ekv/g from the neutral ones. Considering that the size of exchange capacity of phosphate cation-exchange resins depends on pH environment and the initial form of ion-exchange groups, there was examined the sorption ability of synthesized cation exchange resin on [Ca.sup.2 +] ions in Na- and H-forms (Table 2). From the table it is clear that the exchange capacity on ions [Ca.sup.2 +] in the H-form - 0.8-1.0 mg-ekv/g - is slightly inferior to capacity in the Na-form - 3 mg-ekv/g. influence of pH on size of exchange capacity was investigated by the method of potentiometric titration. The curve of potentiometric titration had 2 excesses that testifies to presence in structure of cation-exchange resin functional groups with various degree of dissociation. Seeming constants of ionogenic groups dissociation, found from the titration curves, correspond to p[kappa]-3.4, p[kappa]-7.5 (Table 4).
Presence of ionogenic groups in structure of received cation-exchange resin was also investigated by IR-spectroscopical method. In the IR-spectrum of phosphate cation-exchange resin there are strips of absorption in the field of 750 [sm.sup.-1] corresponding to P-C-linkage, in the area of 1250-2560 [sm.sup.-1] they correspond to P(O)(OH) group. There are also strips of absorption in the field of 750 [sm.sup.-1] corresponding to C[H.sub.2]-P[(OH).sub.2] group. Deformation fluctuations in the field of 825-805 [sm.sup.-1] are connected with 1,2,3,4 substitution in benzene ring.
Absence of characteristic strips of absorption in the field of 1670-1685 [sm.sup.-1] testifies on exhaustion of aldehyde group of furfural. Thus, structure of ionexchange resins received by phosphorylation of polymer synthesized on the basis of benzyl bromide and furfural, can be presented as in the Figure 1.
[FIGURE 1 OMITTED]
Research of kinetic properties of cation-exchange resin
The research of properties on ion-exchange resins with various functionality showed that speed of establishment of ion-exchange balance is substantially defined by speed of diffusion of ions deep into grains of ion-exchange resin. Speed of an establishment of sorption balance also depends on degree of dissociation of acid (basic) groups of ion-exchange resins. Phosphate ion-exchange resins on kinetic properties concede to sulfonic acid ion-exchange resins. We investigated kinetics an exchange of ions [Na.sup.+] [right arrow] [Ca.sup.2+] on received phosphate cation-exchange resin (Tursunov, Mirkamilov, and Nazirova, 1995). For comparison we examined properties of phosphate cation-exchange resin KF-1.
Table 5 shows resulted sizes of static exchange capacity and value of factor of distribution; they provide quantitative characteristic of equilibrium distribution of ions [Ca.sup.2+] between solutions and cation-exchange resin.
From Table 5 data it is visible that received cation-exchange resin does not concede on sorption ability to polymerized cation-exchange resin KF-1.
The important kinetic characteristic of process is the diffusion factor in ion-exchange resin. From Table 6 data it is visible that sizes of factors of diffusion are constant.
The constancy of values of factors of diffusion confirms limiting role of diffusion in particles of cation-exchange resin at an exchange of ions [Na.sup.+] [right arrow] [Ca.sup.2+]. Thus, the received results testify that investigated phosphate cation-exchange resin on sorption and on kinetic properties does not concede phosphate cation-exchange resin KF-1.
Research of thermal stability of received phosphate cation-exchange resin
Thermal stability of received ion-exchange resins was investigated on air and in water; the differential-thermal analysis was used also. Thermal stability was monitored on change of exchange capacity, swelling capacity, weight loss in ion-exchange resin, filtrate oxidability. Heating of phosphate cation-exchange resin in the H-form in water within 30 hours at temperature of boiling of water slightly reduced size of exchange capacity. It is obviously connected with process of thermal dephosphorylation representing hydrolysis reaction. Thus, one can judge on thermal stability of cation-exchange resin considering an increase of acidity of a water extract. Aqueous extracts of phosphate cation-exchange resin after heat treatment had slightly acid reaction (pH of filtrate 4.3-4.8). The size of exchange capacity at all cation-exchange resins decreased for 1%. Swelling capacity samples did not vary; hence, essential changes in structure cation-exchange resin did not occur. Thermostability in water phosphate cation-exchange resin was studied also at 150-180[degrees]C. Change of properties of cation-exchange resin after heat treatment was compared to change of properties of phosphate cation-exchange resins of the RF polycondensation and SF polymerization types. The size of exchange capacity at synthesized cation-exchange resin after heat treatment decreased for 8-10% whereas at RF cation-exchange resin in the same conditions it decreased almost for 65-85%, and at SF on 8%. Thermal stability of cation-exchange resins on air was investigated using of thermogravimetric analysis method. Results of researches showed that heating curves of examineed cation-exchange resin are characterized by two endothermic peaks. The first endothermic peak at 100-140[degrees]C brings dehydration of cation-exchange resin. Eliminating of functional groups at all examinees cation-exchange resin begins at temperature of an order from 200-450[degrees]C (the second endothermic peak). The skeleton of received cation-exchange resin is steady against temperature action. At their heating to 1000[degrees]C within 30 minutes the loss in weight reach 40-60 %.
Sorption of ions of metals
For phosphate cation-exchange resins various types of linkage of metal with ionogenic groups of ion-exchange resin are characteristic: ionic, mixed ionic-coordination and purely coordination. The communication type is defined by ability of this or that metal to formation donor-acceptor complexes and degree dissociation of ion-exchanger.
There was interest to study such properties of received phosphate cation-exchange resin as sorption ability to ions of copper, nickel, calcium, sodium, cobalt and uranyl; to study influence of various factors on process sorption of these cations, and also their mechanism of sorption with application of the IR-spectroscopical analysis. Therefore, interaction of cation-exchange resin in Na- and H-forms with salt solutions of copper sulfate, nickel, cobalt, chloride sodium, calcium and nitrate of uranyl were examined. Results of researches are shown in Table 7 (Tursunov, Gabrielyan, and Suhinina, 1974).
Data in Table 7 testify on influence nature of cation on its sorption. It is found that investigated cations are unequally sorbed by cation exchange resin; on ability to sorption they can be located in the following number:
U[O.sub.2.sup.2+] > [Ni.sup.2+] > [Cu.sup.2+] > [Co.sup.2+] > [Na.sup.+]
Studying of influence of the ionic form of cation-exchange resin on absorption of examinees cation-exchange resins showed that Na-form ion-exchange resin (Table 7) possesses larger sorption ability in comparison with the hydrogen form. Also there was investigated influence of pH environment to sorption of ions of metals by cation-exchange resin.
The data (Tables 7 and 8) testify that received cation-exchange resin possesses enough high sorption and desorption ability to ions of examined metals. To find out mechanism of sorption of specified metals' cations the IR-spectra of cation-exchange resin (saturated with copper and nickel ions) in H- and Na-form were examined.
Spectrum of ion-exchange resin saturated with uranyl ion shows a sharp reduction of intensity of fluctuations in phosphorus-oxygen connection. The same picture is observed in spectra of cation-exchange resin saturated with copper and nickel ions. However, considerable reduction of intensity of this strip for cation-exchange resin saturated with an uranyl ion in comparison with ion-exchange resin saturated with nickel and copper ions indicates on participation of phosphoryl oxygen (P=O) in formation of intracomplex connection of an uranyl ion with P=0 group of cation-exchange resin which has a following structure:
[FORMULA NOT REPRODUCIBLE IN ASCII]
Reduction of intensity of fluctuations of P-OH groups R for cation-exchange resin, containing ions of copper, nickel and sodium, appears with the reduction of quantity of P-OH groups having deformation fluctuations in the range of 2100-2600 [sm.sup.-1]. It means that ions of copper, nickel, sodium are absorbed by cation-exchange resin, basically, at the expense of formation of ionic-coordination connection of a following structure:
[FORMULA NOT REPRODUCIBLE IN ASCII]
where, [Me.sup.2+] - [Ni.sup.2+], [Cu.sup.2+], [Na.sup.+].
The study suggests new way of receiving of polymer with halogen methyl group through polycondensation of furfural with halogenbenzyl (bromide benzyl). The polymer can be used as a polymeric matrix in synthesis of ion-exchange polymers.
The mechanism of formation and structure of the specified polymer were studied. It is established that the polymer contains up to 10-12% of bromine. Reaction of polymeranalogous transformations of the received polymer were studied: by phosphorylation of polymer there was synthesized new, earlier not described phosphate cation-exchange resin with exchange capacity of 6 mg-ekv/g. There were investigated basic kinetic laws of reaction of the polymer phosphorylation depending on temperature. Energy of activation and a constant of process speed at initial and final stages of phosphorylation reaction were calculated. It is established that at A>0.5 a diffusion deep into polymer grains is a limiting stage in phosphorylation process. New heat-resistant anion-exchange resin, containing highly basic groups, was synthesized by polymer amination of trimethylamine. Optimum conditions of synthesis anion-exchange resin were defined.
The new method was developed for synthesis of phosphorus-nitrogen containing ion-exchange resins - using phosphorylation of anion-exchange resin on a basis polyethylenepolyamine, furfural and halogenbenzyls. It was established that synthesized ampholytes possess sufficient high sorption and complexing ability in relation to ions of copper, nickel, uranyl both from sour and alkaline solutions.
It was established that received ion exchangers are characterized by the raised stability to thermal and chemical influences in water and on air. Kinetic characteristics of the received cation exchangers were investigated. It was established that cation exchange resins on speed of an exchange of ions Na+ [right arrow] Ca2+ do not concede a well-known polymerization sulfonic cation KU-2-8 and phosphate cation-exchange resin KF-1.
There were studied sorption and complexing characteristics of received ion-exchange resins among metals: copper, nickel, cobalt, and uranyl-ion, depending on pH-environment, the ionic form of ion-exchange resin, concentration of the investigated cation-exchange resins. It was shown that copper, nickel, cobalt and an uranyl-ion by phosphate cation-exchange resin sorbs at the expense of an ionic exchange and partially at the expense of formation of coordination bonds with ionogenic group of cation-exchange resin.
Pulatov, H., Tursunov, T., Nazirova, R., 2006. "Research new monofunctional sulfonic acid cation-exchange resins and their use in processes of softening waters," Chemistry and Chemical Technology [Khimiya i Khimicheskaya Tekhnologiya], in Russian, pp.65-67
Sherbakov, A., 1962. Furfural [Furfurol], in Russian, Kiev
Tursunov, T., Nazirova, R., 1985a. "Thermal stability of ion-exchange resin on a basis of furfural," Uzbek Chemical Journal [Uzbekskiy Khimicheskiy Jurnal], in Russian, No.4, pp.71-72
Tursunov, T., Nazirova, R., 1985b. "Synthesis of ion-exchange resin by chemical transformation of products of polycondensation of furfural and halogen benzenes," Uzbek Chemical Journal [Uzbekskiy Khimicheskiy Jurnal], in Russian, No.3, pp.48-50
Tursunov, T., Nazirova, R., 1985c. "Synthesis nitrogen-fosforus-contained ion-exchange resins," Uzbek Chemical Journal [Uzbekskiy Khimicheskiy Jurnal], in Russian, No.5, pp.65-66
Tursunov, T., Nazirova, R., 1978. A way of reception of amphoteric resin [Sposob poluchyeniya amfotyernogo ionita], Certificate of authorship, No.512215, Uzbekistan
Tursunov, T., 2009. "Phosphorylation of polymer on a basis of furfural and bromous benzyl," Chemistry and Chemical Technology [Kimyo va kimyo texnologiyasi], in Uzbek, No.4, pp.5456
Tursunov, T., Zajnutdinova, B., Nazirova, R., 1999. "Synthesis of polycondensation anionexchange resins containing high-base groups," Bulletin of TSTU [Vestnik TashGTU], in Russian, No.3, pp.135-40
Turobjonov, S., Pulatov, H., Tursunov, T., Nazirova, R., Mutalov, Sh., 2005. Method of reception of cation-exchange resins [Sposob poluchyeniya kationitov], in Russian, Patent, Republic of Uzbekistan, RUz IAP 03458
Tursunov, T., Mirkamilov, T., Nazirova, R., 1995. "Research in the field of reception and application of ion-exchange polymers on a basis furan compounds," Materials of conference "Topical problems of polymer science" [Polimyerlar faniningu zamonaviy muommolari], in Uzbek, Tashkent, pp.28-30
Tursunov, T., Gabrielyan, N., Suhinina, L., 1974. "Potentiometrical researches of sorption abilities of furan anion-exchange resins," Collection "Research of properties and application of polymeric materials" [Isslyedovaniye svoystv i primenyeniye polimernikh materialov], in Russian, Moscow
Tashkent Institute of Chemical Technology, Uzbekistan
TABLE 1. KINETIC PARAMETERS AT VARIOUS DEGREES OF POLYMER PHOSPHORYLATION ON A BASIS OF FURFURAL AND BENZYL BROMIDE T, Constant of [bar.D] x A=0.1-0.3 [degrees]C reaction speed, [10.sup.-8], [E.sub. [E.sub. K x [10.sup.-3] [sm.sup.2] reac. act.] dif. act.] [sec.sup.-1] /se kJ/mol 50 0.633 0.37 40.28 28.64 60 0.765 0.46 70 0.919 1.40 T, Constant of [bar.D] x A=0.5 [degrees]C reaction speed, [10.sup.-8], [E.sub. K x [10.sup.-3] [sm.sup.2]/se dif. act.] [sec.sup.-1] 50 0.633 0.37 50.04 60 0.765 0.46 70 0.919 1.40 TABLE 2. PHYSICAL AND CHEMICAL PROPERTIES OF SYNTHESIZED IONITES Parameters Unit of Phosphate cation- measure exchange resin Dampness % 15-20 Specific volume of bulked up ml/g 3.2-3.4 ion-exchange resin Static exchange capacitance mg-ecv/g on 0.1 N solutions of: caustic soda 3.8-7.5 muriatic acid - sodium chloride 0.8 Chemical stability. Static mg-ecv/g exchange capacity of ion- exchange resin on 0.1 N solution of NaOH after treatment by solutions: 5 N solution of [H.sub.2]S[O.sub.4] 6.7-7.3 5 N solution of NaOH 6.8-7.7 5 N solution of HN[O.sub.3] 6.75-7.68 Sorption ability to ions: H-form copper 1.2-2.6 nickel 1.2-2.0 uranyl 200-350 Na- form mg-ecv/g copper 1.76-3.08 nickel 2.0-3.74 uranyl 300-450 OH- form copper - Parameters Unit of Amphoteric ion- measure exchange resin Dampness % 14-17 Specific volume of bulked up ml/g 2.8 ion-exchange resin Static exchange capacitance mg-ecv/g on 0.1 N solutions of: caustic soda 3.6 muriatic acid 4.0 sodium chloride - Chemical stability. Static mg-ecv/g exchange capacity of ion- exchange resin on 0.1 N solution of NaOH after treatment by solutions: 5 N solution of [H.sub.2]S[O.sub.4] 3.56 5 N solution of NaOH 365 5 N solution of HN[O.sub.3] 3.62 Sorption ability to ions: H-form copper 1.8-2.0 nickel 2.5-2.7 uranyl 80-100 Na- form mg-ecv/g copper 2.8-3.0 nickel 3.1-3.3 uranyl 220 OH- form copper 2.5-2.8 Parameters Unit of Aminated benzyl measure bromide-furfural polymer Dampness % 40 Specific volume of bulked up ml/g 3.2-3.5 ion-exchange resin Static exchange capacitance mg-ecv/g on 0.1 N solutions of: caustic soda 3.2-3.4 muriatic acid sodium chloride 1.5-2.0 Chemical stability. Static mg-ecv/g exchange capacity of ion- exchange resin on 0.1 N solution of NaOH after treatment by solutions: 5 N solution of [H.sub.2]S[O.sub.4] 3.3 5 N solution of NaOH 3.1 5 N solution of HN[O.sub.3] - Sorption ability to ions: H-form copper - nickel - uranyl - Na- form mg-ecv/g copper - nickel - uranyl - OH- form copper 2.2 TABLE 3. THE BASIC PHYSICAL AND CHEMICAL INDICATORS OF ANION-EXCHANGE RESINS Parameters Unit of Anion-exchange measure resins on a basis of PEPA, furfural and: benzyl benzyl chloride bromide Dampness % 13 11 Static exchange capacitance on 0.1 N mg-ecv/g solutions of: NaCl 1.0-1.1 1.5-2.0 HCl 4.5 4.8 HN[O.sub.3] 4.35 4.85 [H.sub.2]S[O.sub.4] 5.63 5.82 Specific volume of bulked up anion- ml/g 1.8-2.0 2.5-2.8 exchange resin in OH-form Oxidability of a filtrate mg- 3.0-5.0 2-5 [0.sub.2] /g Chemical stability. Static exchange mg-ecv/g capacitance of ion-exchange resin on 0.1 N solution of HCl after boiling during 30 minute by solutions: 5 N solution of NaOH 4.5 4.8 5 N solution of [H.sub.2]S[O.sub.4] 4.3 4.4 Thermal stability. Static exchange mg-ecv/g 4.2-4.22 4.2-4.3 capacitance of anion-exchange resin on 0.1 N solution of HCI after boiling in water during 20 hours TABLE 4. EXCHANGE CAPACITIES OF RECEIVED CATION-EXCHANGE RESINS Cation-exchange Functional group Exchange capacities resins The Static on theoretical, 0.1 n mg-ecv/g solution of NaOH, mg-ecv/g Phosphorylated [FORMULA NOT 4.84 4.5-5.2 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] Phosphorylated [FORMULA NOT 4.8 6.8-7.5 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] with the subsequent oxidation Cation-exchange Functional group Exchange capacities resins Calculated, calculated on under the curves of maintenance potentiometric (%) of titration, mg- sulfur and ekv/g phosphorus, mg-ekv/g Phosphorylated [FORMULA NOT 5.0-5.5 5.5-5.6 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] Phosphorylated [FORMULA NOT 5.0-5.5 6.5-7.5 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] with the subsequent oxidation Cation-exchange Functional group pK1 pK2 resins Phosphorylated [FORMULA NOT - 7.8 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] Phosphorylated [FORMULA NOT 3.4 7.6 benzyl bromide- REPRODICUBLE IN furfural polymer ASCII] with the subsequent oxidation TABLE 5. VALUE OF EXCHANGE CAPACITY AND DISTRIBUTION FACTOR AT SORPTION IONS OF CA2+ WITH CATION-EXCHANGE RESINS Cation-exchange resin Static exchange Coefficient of capacitance, distribution [K.sub.d] mg-ecv/g [Na.sup.+] [right arrow] [Ca.sup.2+], ml/g Obtained cation-exchange 3.96 198 resin KF-1 4.2 210 TABLE 6. FACTORS OF DIFFUSION FOR IONS CA2 + ON CATION-EXCHANGE RESIN IN THE NA-FORM Diffusing ion Contact Investigated cation- KF-1 (gel structure) time, sec exchange resin Bt/t [bar.D], Bt/t [bar.D], [sm.sup.2] [sm.sup.2] /s /s [Ca.sub.2+] 120 0.0025 3.26 0.004 6.5 300 0.002 3.26 0.0026 3.9 600 0.002 3.26 0.0038 4.89 900 0.003 4.89 0.0038 6.1 TABLE 7.SORPTION OF CATIONS OF METALS BY PHOSPHATE CATION-EXCHANGE RESIN 0.1 N H-form solution pH of Sorbed, Coefficient of solution mg-ecv/g distribution, ml/g NaOH 13 6.6-7.6 184 NaCl 8.13 0.8-1.0 11.5 Ca[Cl.sub.2] 6.5 1.1-1.2 120 CuS[O.sub.4] 4.8-5.0 1.2-1.3 66 CuS[O.sub.4] 11 2.64-2.7 733 CuS[O.sub.4] - - - NiS[O.sub.4] 7.6 1.1-1.2 20 NiS[O.sub.4] 10 2.0-2.1 84 NiS[O.sub.4] - - - NiS[O.sub.4] - - - CoS[O.sub.4] 8 2.0-2.05 35 CoS[O.sub.4] - - - CoS[O.sub.4] - - - U[O.sub.2] [(N[O.sub.3]).sub.2] 4.5 150-200 300 U[O.sub.2] [(N[O.sub.3]).sub.2] U[O.sub.2] [(N[O.sub.3]).sub.2] 0.1 N Na-form solution pH of solution Sorbed, mg-ecv/g NaOH - - NaCl - - Ca[Cl.sub.2] 6.5 3.57-3.6 CuS[O.sub.4] 4.8-5.0 1.75-1.8 CuS[O.sub.4] 11 3.08-3.1 CuS[O.sub.4] 2.35 1.0-1.1 NiS[O.sub.4] 2.25 1.0 NiS[O.sub.4] 3.8 3.6 NiS[O.sub.4] 7.6 2.0 NiS[O.sub.4] 10 3.75-3.8 CoS[O.sub.4] 2.36 0.8-0.9 CoS[O.sub.4] 3.18 2.4 CoS[O.sub.4] 8 2.65 U[O.sub.2] [(N[O.sub.3]).sub.2] 2.02 95-100 U[O.sub.2] [(N[O.sub.3]).sub.2] 3.12 240-250 U[O.sub.2] [(N[O.sub.3]).sub.2] 4.5 450 TABLE 8. DESORPTION OF IONS OF METALS FROM CATION-EXCHANGE RESIN Desorbing Sorbed, Desorbing solution Desorbed, cation mg-ecv/g, [H.sub.2]O 2 N solution of mg-ecv/g, ml/g [H.sub.2]S[O.sub.4] ml/g and 2 N NaHC[O.sub.3] calcium 3.57 0.2 2.9 3.1 copper 3.08 0.06 2.7 2.76 nickel 3.6 0.56 2.83 3.39 cobalt 1.4 0.2 0.9 1.1 uranyl-ion 450 0.0 396 396
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|Publication:||Applied Technologies and Innovations|
|Date:||Mar 1, 2012|
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