KU-2-8 cation exchanger

The cation exchange experiments were performed with KU-2 cation exchange resin (equilibration time 7 days) in HNOs-NaNOs solutions, the colorimetric studies with Arsenazo III in both HNOs-NaNOs and HC104-NaC104 media and with Thoron I in HNOs-NaNOs solutions. The pH values were adjusted by dilution of the stock solutions with 0.1 M HNO3 or 0.1 M HCIO4 and addition of NH3 solution and measured with a glass electrode. Details on the electrode calibration are not reported. 

SYHTHESIS OF SORBATE ESTERS OF LOWER ALIPHATIC ALCOHOLS WITH THE USE OF KU-2 CATION EXCHANGE RESIN AS CATALYST. 

Figure 10.13 Fraction of zirconium removed onto a KU-2 cation exchange resin as a function of acid concentration and that predicted using Eg. (10.1) (solid line).

Knorr s. Konigs Koch-Haaf synthesis 14, 773 Kolbe electrolysis 23, 887 K5nig s. a. Zincke K5nigs-Knorr reaction 1, 218 modified 22, 228 23. 242 KU-1 cation exchanger 11, 232 suppl. 21 KU-2 cation exchanger 7, 730 suppl. 21 11, 232 suppl. 22 22,3... 

Furfural-salicylic acid and furfural-P-naphthalenesulfonic acid resins possess thermal stabilityexceeding that of KU-1 (sulfonated phenol-formaldehyde resin) and approaching that of KU-2 (sulfonated SDVB copolymer). The heat resistance of toluenesulfonic acid-furfural resin is quite similar to that of KU-2 resin. The improved thermal stability of furfural-based cation-exchange resins is attributed to the presence of heterocyclic and aromatic rings in these resins. 

Ethers. The polycondensation of diphenyl ether and furfural (1 1.5mole ratio) in presence of sulfuric acid yields a resin which has been sulfonated by sulfuric acid at 50 °C for 10 h to give a cation-exchange resin The swelling and the exchange capacity of the product increase with the amount of sulfuric acid present during the polycondensation and are higher for a resin obtained by polycondensation in carbon tetrachloride than the one prepared in absence of solvent. The thermal stability of sulfonated diphenyl ether-furfural resin is more than that of KU-1 and comparable to that of KU-2. The sulfonic acid resin derived from the copolymer obtained by the polymerization of diphenyl ether and furfural at a mole ratio of 1 2 in carbon tetrachloride has optimum adsorption and catalytic activity... 

For example, the equilibrium distribution of cesium and rubidium between sulfophenolic cation exchanger KU-I and neutral solution is characterized by the value ag = 1.5-1.6 while in alkaline solution = 1.8-2.0. In the latter case sorption capacity is 2.5-3.0 times as great as it is in neutral solution [34]. 

Figure 24 A scheme for KNO3 production (sulfonate cation exchanger KU-2 X 8 3.0-4.0 mol/dm solutions) (1) column for KNO3 synthesis (2) resin regeneration column (3,4) systems for electrolyte displacement (5-8) tanks.

The dependence of HETP upon solution flow rate when exchanging the H -Na pair of ions between 0.2 M chloride solution and cation exchanger, KU-2 x 8, with beads 0.25-0.50 mm in diameter, has been compared in the literature for columns of different types [76,84]. The pulse method which has been used possesses the advantage that with the pulsed injection of a small amount of substance all physicochemical and hydrodynamic characteristics of the system remain invariably determined by the primary substance, Na" " ion in this case. Dynamic parameters obtained characterize the process when the concentration range of impurity is low. 

Upon the exchange of KCl from 3.0 to 4.0 mol/dm solutions with sulfonate cation exchanger KU-2 x 8 in the NHJ -ion form [92,93] in both the hxed bed and in the alternately moving solution and ion exchanger the sorption front is narrower when KCl solution is injected from below than when it is injected from above. This effect is particularly noticeable at low rates of solution flow. Stopping the process in the latter case leads to dispersion of the front increasing with time. In the former case even the interruption in operation for one to two days does not result in appreciable disturbance of the sorption front. 

Phenols are alkylated mainly in the / 0ra-position 659 for example p-tert-butylphenol is formed in 95% yield from phenol and isobutyl alcohol in this case a cation-exchange resin KU-2 was used, with 4 hours heating at 130°.660... 

By contrast, with a cation exchange resin (KU-2), 2-alkylphenols reacted in p-... 

Figure 16.5 Sorption isotherms at 25°C of vapors of (1) n-hexane, (2) acetone, (3) methanol, and (4, 5) water onto (1-4) sulfonated Styrosorb 1 crosslinked with p-xylylene dichloride to 100% and onto (5) cation exchanger KU-23, both taken in H+ form. (After [381].)...

It is well known that corrosion processes are enhanced if there are high levels of impurities in the water. Therefore, to keep the level of impurities low, an ion exchange purification system has been employed since startup in the MIR reactor coohng pool. This system includes a heat exchanger, a pump, two filters with a total capacity of 800 L, a flowmeter, shut-off valves and other fittings. The filters are filled with Russian made nuclear grade ion exchange resins KU-2-8 (cationic) and AV-17-8 (anionic) in the ratio of 2 1. This system provides reduction of the specific p activity by more than a factor of 10. When this index drops to a factor of 2, the resin is replaced otherwise, as a rule, it is replaced once a year. 

Cyclohexene-3-carboxylic acid allowed to react with tetrahydrofuran and HCI in the presence of KU 2 (H-form) cation exchanger -> 6-chlorobutyl cyclohexene-3-carboxylate. Y 69-77%. F. e. s. B. F. Pishnamazzade and N. N. Nabiev, Azerb. Neft. Khoz. 52 (7), 34 (1972) (Russ) C. A. 77, 151750. 

Figure 3 Thermodynamic functions of ion exchange between amino acids and hydrogen forms of gel cation exchanger KU-2-8 (open symbols) and macroporous cation exchanger KU-23 (30/100) (filled symbols) Phe (left panels), Tyr (central panels), and ZyV (right panels)...

Figure 4 Hydration in the system single charged lysine ion - cation exchanger with (left) and without (right) sterio restrictions. The schemes have been designed on base of IRS data for gel KU-2-8 and macroporous KU-23 (30/100) materials correspondingly. The angles between drown bonds are not representative...

Figure 5 Composition of cation exchanger phase for gel KU-2-8 (curves 1 and 3) and macroporous KU-23 (30/100) (curves 2 and 4) cation exchangers differently loaded with lysine. Curves 1 and 2 show average number of lysine molecules in associates, Ha, curves 3 and 4 show number of water molecules per sulfuric group of the exchanger. Reprinted from Vestnik Voronezhskogo Gosudarstvennogo Universiteta[l2 V. F. Selemenev...

Figure 6 Breakthrough curve of Tyr sorption on OIT form of anion exchanger AV-17-2P (left panel) and form of cation exchanger KU-23 (30/100) (right panel). 1 - concentration of tyrosine, 2 - pH, 3 - concentration of Cl (left) or Na (right). C/Co is the ratio between the concentration at the column outlet and the concentration of the solution supplied in the column V/V0 is the ratio between the volume of pumped solution and initial volume of the ion exchanger loaded in the column (column diameter was 1 cm, initial height of the bed was 20 cm). Reprinted from Vestnik Voronezhskogo Gosudarstvermogo Universitet( 2 V. F. Selemenev...

The solution is pumped through a column containing a strong cation exchange resin in NH/ form (for example, KU-2-8). Amoimt of the solution treated in one cycle, V/Vq, is 10-12 volumes per volume of the sorbent bed. The column traps lysine and major part of melanoidins. Due to a frontal chromatography process, a major part of alanine can be... 

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