Synthesis and characterization of N,N,N',N'-tetrabutylsuccinamide (TBSA)was carried out and used for the extraction of U(VI) and Th(IV) from nitricacid solutions. Toluene was found to be the most suitable diluent for TBSAcompared with the other diluents tested. Extraction distribution ratios (D)of U(VI) and Th(IV) have been studied as a function of aqueous HNO 3 concentrations,NO3 – ion concentration, TBSA concentration and temperature.The results obtained indicated that U(VI) and Th(IV) are mainly extractedas UO2 (NO3 ) 2 . 2TBSA and Th(NO3 ) 4 . TBSA, respectively, and the IR spectra of the extractedspecies have been investigated. The values of thermodynamic functions havebeen calculated. Back-extraction of U(VI) and Th(IV) from organic phases wasalso studied.
The concept of using paper chromatography on papers impregnated with liquid anion or cation exchangers is extended to the
separation of trace elements through filtration on filter papers loaded with suitable extractant. The uptake of uranium, thorium
and lanthanum from HCl and HNO3 media of different molarities by a filter paper treated with tri-octyl amine (TOA) is investigated. The effect of the different
parameters on the uptake of the studied elements is experimented. A simple and fast radiochemical procedure is developed for
the separation of La, Th and U from each other.
Tributyl phosphate was used in reprocessing of spent nuclear fuel inthe Purex process. The amount of uranium retained in the organic phase dependson the type of TBP/diluent. Destruction of spent TBP is of high interest inwaste management. The use of the oxidative degradation of TBP diluted withkerosene, carbon tetrachloride, benzene and toluene using potassium permanganateas oxidant was carried out to produce stable inorganic dry particle residuewhich is then immobilized in different matrices. The different factors affectingthe destruction of spent waste were investigated. The uptake and decontaminationfactor for both 152, 154Eu and 181Hf and the analysisof the final product have been studied.
The present overview presents a brief survey on the liquid-liquid extraction mechanism of metal chelates and adducts, the different reported reaction models and the most common methods used to follow the kinetics of extraction process are given. The effect of the different phenomena affecting the extraction rate and the importance of the kinetic information in connection with technical processes and counter-current modelling are also discussed.
3-Formyl-4-hydroxy-N-methyl 2(H) quinoline (FHMQ) was synthesized and characterized. This compound was found not soluble in
water or nitric acid solutions of different concentration. The uptake of Zr and Th from nitric acid by FHMQ has been investigated.
The effect of shaking time on the percent uptake was studied. It was found that the equilibrium uptake of Zr is reached in
one step after 2 hrs while in case of Th 4 hrs was required to reach equilibrium. The effect of nitric acid, metal ion and
FHMQ on Zr uptake was studied. Studies on the retention capacity of 3-formyl-4-hydroxy-N-methyl 2(H) quinoline showed that
its capacity decreases by increasing the nitric acid concentration for both Zr and Th. From the results obtained a selective
method for separation of Zr from Th and U(VI) was developed using a floating bed column.
The effect of temperature on the extraction of the trivalent actinides Am3+, Cm3+ and Cf3+ with the liquid cation exchanger dinonylnaphthalenesulphonic acid (HD) in toluene is studied. The different thermodynamic
functions of this system are determined from the experimental results. It is found that the free energy variation for the
extraction of these metal ions by HD is mainly determined by the entropic terms arising from the hydration-dehydration process
of the exchanged ions.
The extraction of radio-mercury(II) by PTTDT was investigated as function of diluent, hydrochloric acid concentration, extractant
concentration and certain foreign compounds in the aqueous phase. The extraction was found to be quantitative when chloroform
was used as diluent and at low HCl or high PTTDT concentrations. Neither the presence of boric acid, nor several metal salts
(NaF, CuSO4, ZnSO4 or Na2SO4) had any effect on the E%. The presence of chloride or bromide lowers the E% considerably. A radiochemical procedure was
developed to pre-concentrate mercury from artifical sea water using an organic: aqueous phase ratio of 1∶100.
Tin(IV) antimonate (SnSb), cerium(IV) antimonate (CeSb), silicon(IV) antimonate(SiSb) ant titanium(IV) antimonate (TiSb) were
prepared under various conditions. The ion-exchange properties and the thermal stability of these materials were examined
in order to elucidate their applicability to the processing of radioactive liquid wastes. Capacity, equilibrium measurements,
adsorption isotherms and the selectivity patterns for Cs+, Sr2+, Co2+ and Eu3+ ions on these sorbents at different conditions were determined. The effect of high concentrations of salts and complexing
agent as interfering ions in the feed solutions on the distribution coefficient of the metals, mentioned above, was tested
as a function of [HNO3]. Based on the results obtained, practical separation experiments on column were performed.
The removal efficiency of moderate levels of radon from groundwater supplies was evaluated using the diffused bubble aeration
technique. An aeration system was designed, constructed and operated for that purpose. The effect of air-to-water ratio and
detention time on radon removal were evaluated through 32 runs. The possibility to reduce the radon activity in the influent
stream to the U.S. Environmental Protection Agency proposed maximum contaminant level (MCL) was verified through many alternative
combined values of both air-to-water ratios and detention times. The results showed that at detention time of 19 minutes and
air-to-water ratio of 12, the average radon removal is about 97%. The stripping constant characterizing this system was calculated
and the removal efficiency at extended values of detention time was predicted. The data obtained are site specific, being
dependent on container size, type of diffusers, temperature, and influent radon radioactivity.
The extraction behavior of octahedral and tetrahedral cobalt(II) complexes from aqueous nitrate medium was studied in the
system 8-hydroxyquinoline (HOX) and dibenzo-18-crown-6 (Db 18C6) or dibenzylamine (DBA) in chloroform at different temperatures
to evaluate the thermodynamic functions as well as the equilibrium constants of each reaction. The stoichiometry of the extracted
organic phase species were established to be Co(OX)2·Db18C6 for the octahedral cobalt and Co(OX)2·DBA for the tetrahedral cobalt.