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The time to establish adsorption equilibria during
As a result of high-precision measurements of
the formation of monomolecular layer slowed ~ 4 hours, and the second layer is formed for ~ 2 h.
Conclusion In this work we determined that the migration of Na+ cations on the basal and lateral faces under the influence of adsorbed water is completely reversible. The number of Na+ cations on the basal surface equals 93 ^mol/g. About 60% of the adsorbed carbon dioxide is involved in the adsorbate-adsorbate interactions, which is accompanied with the growth of the adsorption heat and its passing through a maximum. The mobility of the CO2 molecules on the surface of Na-illite is higher than in the liquid.
References:
the adsorption heats of benzene on illite, we revealed wavelike property of heats ofbenzene when the surface is filled.
Each stage reflects the stoichiometric interaction of benzene with Na+ cations. First two stages correspond to adsorption.of benzene with Na+ cations in the ratio 1:1. Further adsorption takes place in the intermediates between the adsorbed molecules. On the total surface approximately 4 monomolecular layers are formed. The condition of benzene on the surface of Na-illite is liquidlike.
1. Diaz M., Farmer V.C, Prost R. Characterization and assignment of far infrared absorption bands of K+ in muscovite//Clays and Clay Minerals. - 2000. - V. 48, №. 4. - P. 433-438.
2. Pluijm Ben A., Lee J. H., Peacor D. R. Analytical electron microscopy and the problem of potassium diffu-sion//Clays and Clay Minerals. 1988. V.36. No. 6. P. 498-504.
3. Boddenberg B., Rakhmatkariev G. U., Viets J. Thermodynamics and Statistical Mechanics ofAmmonia in Zeolites NaZSM-5//Ber.Bunsenges Phys. Chem. - 1998. - V. 102. - P. 177-182.
4. Boddenberg B., Rakhmatkariev G. U., Greth R. Statistical Thermodynamics of Methanol and Ethanol Adsorption in Zeolite NaZSM-5//J. Phys.Chem. B. -1997. - V. 101. - P. 1634-1640.
5. Mentzen B. F., Rakhmatkariev G. U. Host/Guest interactions in zeolitic nonostructured MFI type materials: Complementarity of X-ray Powder Diffraction, NMR spectroscopy, Adsorption calorimetry and Computer Simulations//Uzbek. Khim. Zh. - 2007. - № 6. - C. 10-31.
Turobjonov Sadriddin Maxamaddinovich, Tashkent Institute of Chemical Technology, Rector E-mail: tur_sad@mail.ru Rakhimova Latofat Sobirdjanovna, Tashkent Institute of Chemical Technology, Senior lecturer
E-mail: latofat.2011@mail.ru
Synthesis of phosphoric acid cation- exchange polymer of polycondensation type
Abstract: Were studied the reaction of phosphorylation obtained diphenyloxide-furfural polymer for produce the new phosphoric acid exchange polymer with capacity of 5,8-6,0 mg-eq/g. Investigated the influence of the nature and concentration of the phosphorylating agent, the temperature and duration of the phosphorylation reaction, concentration and nature of the catalyst on the properties of phosphoric acid cation exchange polymer. On the basis of studies to determine the optimum conditions for obtaining cation exchanger.
Keywords: Diphenyloxide-furfural polymer, phosphorylation, cation exchanger, swelling, static exchange capacity.
Introduction. Among the known phosphoric acid cation ion exchangers have a special meaning. They are characterized by a number of valuable properties: high capacity, selectivity to ions of certain metals. It should be also noted chemical and thermal stability
of the cation exchanger from the carbon-phosphorus, especially aromatic-phosphorus which is significantly higher than for ion-exchange polymers with carbon-sulfur, carbon-nitrogen or carbon-carbon, thermal destruction of which begins with the destruction of
Section 10. Chemistry
relationships that perpetuate ionic groups in the polymer matrix [1]. High radiation resistance of phosphoric acid cation compared to other types of ion exchangers allows to use their in the environments with high radiation resistance [2]. In practice, most phosphoric acid cation prepared by methods of chemical transformations. Conditions of phosphorylation process of obtained by us diphenyloxide-furfurol (DPhO) polymer for obtaining cation exchanger were chosen under which the experience gained in relation to the phosphorylation reaction of low- and high-molecular compounds [3].
During the phosphorylation reaction of the obtained polymer on purpose obtaining cation exchanger with
Table 1. - The comparative values of the acid cation exchange polymers with
good basic properties investigated the influence of the reaction duration, the swelling of the polymer, the concentration of PCl3 and ratios of the starting materials on the properties of the cation exchanger.
The content of furfural in obtaining diphenyloxide-fUrfUral polymer varied between 1,0-2,0 moles furfural per mole of DPhO. Results obtained indicated that the cation-exchange with an increasing concentration of furfural 1,0-1,5 moles of the exchange capacity varied little. The swelling with increase content of furfural is reduced due to an increase in the degree of cross linking of the polymer (Table 1).
physical-chemical properties of phosphoric different ratios of the starting materials
Parameters M ol ratios of furfural to DFO
1:1 1,5:1 2,0:1
Wetness,% 14 15 18
Bulk weight, г/мл 0,15 0,18 0,13
Specific volume, мл/г 5,6 6,3 4,8
SEC to 0,1N solutions, mg-eq/g:
NaCl 1,6 1,8-19 0,8
NaOH 3,2 5,8-6,0 2,6
CaCl2 0,6-0,8 1,8 1,4
MgSO4 0,4 1,5 0,8-1
CuSO4 1,0 1,2-1,3 0,6
NiSO -4- 0,6 0,8-1,0 0,4
The minimum content of furfural, providing a sufficiently high exchange capacity -5,8-6,0 mg-eq/g for sufficient swelling -6,3 ml/g of 1,5 mol per 1,0 mol of DPhO. Thus, it is shown that the properties of the cation exchanger is significantly influenced by the ratio of furfural to the DPhO. Good results have been achieved by us in the preparation of a cross linked diphenyloxide-furfural polymer with subsequent phosphorylation. Phosphorylation rate largely depends on the degree of cross linking. The highly cross linked polymer, the
slower the diffusion process and requires a long time to complete the reaction (Table 1). Phosphorylation occurs unevenly, especially phosphorylated surface layer of the polymer grains, which may arise due to stresses and breaks that lead to the destruction of the polymer. In order to eliminate internal stress and improve the kinetic and mechanical properties of the polymer before the phosphorylation was swollen in various solvents. Were used: PCl3, dichloroethane, dimethylformamide (DMF), ethyl alcohol (Table 2).
Table 2. - Influence of the pre-swelling diphenyloxide-furfural polymer on the properties of the cation exchanger
Solvent Swelling of the polymer in a solvent, ml/g SEC to 0,1N solution of NaOH mg-eq/g Specific volume of swollen cation exchanger in water ml/g
PCI 170 5,8-6,0 6,3
Dichloroethane 120 4,0-5,0 3,2
Dimethylformamide (DMF) 156 5,6-5,8 5,6
ethyl alcohol 110 4,0-5,0 2,8
Note: The duration of swelling — 8 hours Terms phosphorylation temperature -70 ± 5 °C, Duration — 6 hours.
The best results are obtained using a solution of PCl3, which penetrates deeper into the particle, significantly broadens the molecular grid and facilitates phosphorylation. As a result of the exchange capacity reaches 5,8-6,0 mg-eq/g.
Phosphorylation of the diphenyloxide-furfural polymer conducted by phosphorus trichloride in the presence of anhydrous aluminum trichloride at reflux the reaction mixture according to [4]. To establish optimal conditions for the phosphorylation reaction of the obtained polymer and to achieve high conversion were studied the influence of the reaction duration, the concentration of phosphorus trichloride. The reaction was conducted by in a ratio of phosphorus trichloride
SEC, mg-eq/g
and aluminum chloride in 4 mol:2mol-base polymer. When this phosphorus trichloride was not only a phosphorylating agent, and environment that allows swelling of the polymer.
Figure shows that the process of phosphorylation of pre-swollen polymer phosphorus trichloride is rapid. Based on the data obtained for the optimum time phosphorylation took 6 hours. Phosphorylation of the furfural-diphenyloxide performed phosphorus trichloride polymer, where in the polymer grains to swell at room temperature for 170%. Figure also shows the degree of phosphorylation of the concentration of phosphorus trichloride (in moles based on the moles of polymer) in the reaction mixture.
time, hour
2 4 6 PCI3 mole
Fig. 1. Kinetics of phosphorylation diphenyloxide-furfural polymer: 1 -on the duration, t; 2 concentration, PCl3 The highest degree of conversion is achieved by using of HNO3, at 25-30oC for 6 hours. The oxidized polymer
four moles of phosphorus trichloride to base — mole of polymer. Hydrolysis phosphorylation received cation having phosphinous group, it's exchange capacity of 4,55,0 mg-eq/g swelled in 0,1 N NaOH solution at 120%, in water at 15-20%. Oxidation obtained phosphinous cation in phosphinic acid, carried out using 25% solution
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retains the original shape and appearance. Cation exchanger has a capacity of NaOH to 6,2-5,8 mg-eq/g, it is multifunctional with a weakly-srednokislotnymi and ionic groups. Cation swelling in water is 50% and the NaOH solution is increased to 170-180%.
1. Leykin Yu., Davankov A., Sergeeva L., Cherkasova T., Korshak V. Synthesis of monofunctional phosphorus cation groups mono alkyl-substituted polystyrenephosphonid acid//J. HMC. 1967, T. 97. P. 744-748.
2. Kiselova Ye., K. Chmutov, V. Krupnova. The study radiation resistance of ion exchange resins.J//Phyz. chemistry, 1962, T36., № 11. P. 2457-2465.
3. Rakhimova L. S., Abdutalipova N. M., Nazirova R. A., Tursunov T. T., Berdieva M. I., Mutalov Sh. A. Synthesis and property of new polycondensation type of ion exchanging polimer. The advanced science journal Issn 2219-746x (print); 2219-7478 (online)Volume 2014 issue 3. P. 91-96.
4. Rakhimova L. S., Abdutalipova N. M., Nazirova R. A., Tursunov T. T., 2015. stock formation of phosphorus con-tening cation-exchange polymer [Sposob poluchyeniya fosorsoderjashego kationita], in Russian, Patent, Republic of Uzbekistan, RUz №IAP 05133.
