New Composite Materials for Decreasing of Radioactive Molecular Iodine in the Water Coolant on the Working and New Developed NPPS

Author(s):  
S. A. Kulyukhin ◽  
L. V. Mizina ◽  
A. A. Tishina

The sorption of 131I−, 131IO3−, I2 and CH3131I from water solutions at 25°C on new composite materials obtained by modifying of cation-exchange resin KU-2 was investigated. It was established, that the given materials are capable to absorb I2 both from distilled water, and from a water coolant of the WWER-type NPPs, with distribution factors Kd more than 103 cm3/g at V/m = 100. Thus, it was found, that practically full I2 absorption (more than 95.0%) was achieved for 15 min. It was shown, that anion-exchange resin AV-18 is capable to adsorb CH3131I from a water solutions with distribution factors Kd more than 300 cm3/g at V/m = 100.

Weed Science ◽  
1979 ◽  
Vol 27 (3) ◽  
pp. 257-262 ◽  
Author(s):  
J. S. Arnold ◽  
W. J. Farmer

The adsorption of picloram (4-amino-3,5,6-trichloropicolinic acid) was determined on an Aiken silt loam, on three cation exchange resins and on a single anion exchange resin. Adsorption data were evaluated using parameters in the Freundlich equation and their dependance upon cationic composition of the exchange complex, the ionic composition of the equilibrium solution, and the equilibrium solution pH. For the Aiken soil saturated with metallic cations the order of decreasing picloram adsorptive capacity was Fe+3= Cu+2> Al+3> Zn+2> Ca+2> native soil. Increases in adsorption compared to the native Aiken soil could be explained on the basis of decreases in the equilibrium solution pH except for Fe+3, Zn+2, and especially the Cu+2treatments. The adsorptive capacity of the Aiken soil was altered by the addition of several salts simulating addition of fertilizer salts. The Cu+2and Zn+2salts were the only treatments showing increased adsorption which could not be explained readily by pH changes. KH2PO4and NH2CONH2(urea) reduced picloram adsorption. Dowex 50-1 × 4, a strongly acidic cation exchange resin, showed increased picloram adsorptive capacity in the order Cu+2> Al+3> Ca+2> Zn+2= H+. Cellex CM, a weakly acidic cellulose exchanger had increased adsorptive capacities in the order of Cu+2> Ca+2> Al+3> Na+> Fe+3> Zn+2. Picloram adsorption by an anion exchange resin at pH 6.1 was nearly 100%. These results suggest that complex formation of picloram with polyvalent cations on the exchange complex is likely especially for Cu+2and to a lesser extent Fe+3and Zn+2. In soils such complex reactions would most probably involve organic matter, polyvalent cations, and picloram. The formation of chelate ring species is proposed.


Weed Science ◽  
1969 ◽  
Vol 17 (1) ◽  
pp. 16-19 ◽  
Author(s):  
David L. Coffey ◽  
G. F. Warren

A root bioassay was used to compare the adsorption of herbicides by activated carbon with that of muck soil, bentonite clay, a cation exchange resin, and an anion exchange resin. The effectiveness of different adsorbents was determined by comparing the concentrations of herbicide required to give 50% root inhibition of the test plant. Of eight herbicides tested, six were more strongly adsorbed by activated carbon than by any of the other adsorbents. The relative amount of adsorption by activated carbon as measured by the reduction in biological activity was as follows: isopropyl N-(3-chlorophenyl)-carbamate (CIPC) > α,α,α,trifluro-2,6-dinitro-N, N-dipropyl-p-toluidine (trifluralin) > 2,4-dichlorophenoxyacetic acid (2,4-D) > N,N-dimethyl-2,2-diphenylacetamide (diphenamid) > dimethyl 2,3,5,6-tetrachloroterephthalate (DCPA) > 4,6-dinitro-o-sec-butylphenol (DNBP) > 3-amino-2,5-dichlorobenzoic acid (amiben). The biological activity of 1,1'-dimethyl-4,4'-bipyridinium salt (paraquat), a cationic herbicide, was not reduced by activated carbon, but was reduced by bentonite clay and the cation exchange resin. DNBP was more strongly adsorbed by the anion exchange resin than by activated carbon. Desorption from activated carbon varied greatly for the herbicides tested. The most readily desorbed herbicide was 2,4-D while CIPC and DNBP showed little or no desorption.


Weed Science ◽  
1973 ◽  
Vol 21 (3) ◽  
pp. 224-227 ◽  
Author(s):  
John R. Abernathy ◽  
Loyd M. Wax

Investigations of the behavior of 3-isopropyl-1H-2,1,3-benzothiadiazin-(4)3H-one 2,2-dioxide (bentazon) in water solutions have shown that it was anionic in neutral solutions by exhibiting a strong movement toward the anode in an electrical field. The herbicide was not adsorbed by any of twelve selected Illinois soils or by the cation exchange resin, carboxymethylcellulose (CMC), but was almost completely adsorbed by charcoal and by the anion exchanger, diethylaminoethylcellulose (DEAE). Bentazon moved with the water front on soil thin-layer plates as well as through soil columns.


1974 ◽  
Vol 54 (2) ◽  
pp. 179-186 ◽  
Author(s):  
RAJ GROVER ◽  
ALLAN E. SMITH

The adsorption of acid and dimethylamine salts of 2,4-D and dicamba was studied on Canadian prairie soils and various other adsorbents, using slurry-type adsorption experiments. The amount of adsorption of both the acid and dimethylamine forms of the two herbicides was minimal. The results were explained on the basis of dissociation of the acidic and dimethylamine salts to the respective anionic forms in the near-neutral prairie soils. This conclusion was supported by (1) the strong adsorption of these herbicides to the anion-exchange resin but not to the cation-exchange resin; (2) the strong adsorption of the 14C-dimethylamine cation to these soils; and (3) the leaching patterns of the 14C-dimethylamine salts of both herbicides from soils and resins. Only the anionic species were eluted from columns containing soils and cation-exchange resin whereas only the 14C-dimethylamine cation eluted from columns containing anion-exchange resin. Both forms of 2,4-D and dicamba were strongly adsorbed to activated charcoal, cellulose triacetate, and peat. There was little or no adsorption of these herbicides to montmorillonite and kaolinitic clays, cellulose powder, or wheat straw.


Author(s):  
Sayan E. Salmenbayev ◽  
◽  
Nazgul K. Nurgaysinova ◽  
Gani M. Yessilkanov ◽  
Аray E. Temirzhanova ◽  
...  

The relevance of the research is caused by the need to develop a methodological base for determining 151Sm content in the soil cover of radioactively contaminated territories of Kazakhstan. The developed method for the determining of 151Sm will make it possible to assess the levels of soil contamination with this radionuclide, to determine the character of its spatial distribution, to allow estimating the internal exposure doses for the personnel and the population. The aim of the research is to carry out the isolation and radiochemical purification of samarium isotopes from acid solutions via using ion-exchange resins AV 17×8 and KU-2. Objects: salt solutions based on nitric and hydrochloric acid containing the stable isotopes of some natural, artificial β-emitters and isotopes of U and Th. The concentrations of nitric and hydrochloric acids were equal to the concentrations of the same acids used in the routine analysis of Pu and Am. Concentrations of chemical elements were determined using the Agilent 7700x quadrupole mass spectrometer and the iCAP 6300 Duo atomic emission spectrometer. The results of the experiments on the isolation and radiochemical purification of samarium isotopes from acidic solutions using anion-exchange resin AV 17×8 and cation-exchange resin KU-2 have been presented. It has been shown that the Sm-fraction can be purified from alkaline elements, Tl and U isotopes using the KU-2 cation-exchange resin. In turn, the isotopes U, Fe and Co can be removed using an anion exchange resin in 9M HCl media.


Author(s):  
Mykola Gomelya ◽  
Andrii Holiaka

Experimet to determine the effectiveness of iron-containing redoxites on the efficiency of water deoxidation. In the course of the study, the dependence of the efficiency of water deoxidation on the filtration rate was determined. The filtration rate was varied in the range from 5 to 25 mph. The residual oxygen content and the dissolved iron content in the water were determined. It was shown that with increasing filtration rate within these limits, the residual oxygen concentration increases from 0.1-0.2 mg/dm3 to 0.9-1.0 mg/dm3. The residual oxygen content depends not only on the filtration rate but also on the reaction of the medium. An increase in the residual oxygen concentration with increasing pH of the medium from 6.7 to 10.0.  Residual iron content depends little on both the filtration rate and the reaction medium and in all cases did not exceed 0.2 mg / dm3. In this work, the dissolution of iron in general was determined by preliminary preparation for the work of iron-containing redoxite. When used in the installation scheme, in addition to the column with iron-containing redoxite, also columns with cation exchange resin KU-2-8 in Na-form, almost complete removal of iron ions from the water and natriation softening of tap water was noted. In the case of sodium-cationized water, the extraction of iron from water will be observed for a long time, given the low concentration of iron ions in the water and the high capacity of the cation exchange resin in iron ions. In addition, sorbed iron (II) ions on the cation exchange resin are oxidized by oxygen residues to iron (III). The latter, at elevated pH, are hydrolyzed, which is the reason for the restoration of capacity and cation exchange resin by divalent iron cations. In the case when after the column with iron-containing redoxite used anion exchange resin AB-17-8 in sulfite form, complete extraction of oxygen from water was achieved. Given that the oxygen concentration in water with the use of iron-containing composite decreased by 10-40 times, the load on the anion exchange redox will decrease proportionally, which means that the duration of the anion exchange redox filter cycle will increase in the same proportion. The use of iron in the second stage of the anion exchange resin in the SO32- form remained unchanged, but complete oxygen extraction was achieved. The option is quite promising for implementation.


Sign in / Sign up

Export Citation Format

Share Document