[en] A large thorium deposit (380.000 tonne ThO₂) has been found in Eskisehir-Beylikahir area in Turkey. Representative sample of 1000 Kg. thorium ore was taken from this deposit for the pre-concentration studies. Thorium pre-concentrate which has 1.41% Th0₂ grade and minus 0.105 mm. particle size was obtained after the physical treatment tests. Sulphuric acid leach was conducted on the thorium pre-concentrate and the thorium extraction recovery was over 90%. After these leach tests with sulphuric acid, thorium was precipitated as a sulphate from the leach slurry with 96% recovery. Thorium sulphate cake was dissolved in HCl and precipitated with ammonia to give a thorium hydroxide. During this process, aluminium iron and calcium were separated from the thorium. The thorium hydroxide was dissolved in nitric acid and the solution was evaporated to solid thorium nitrate. (author)

No abstract available

[en] Published in summary form only

[en] Densities of a large number of mixed uranyl nitrate-thorium nitrate solutions were measured with pycnometer. By the least squares analysis of the experimental result, an empirical formula for determining water content of mixed uranyl nitrate-thorium nitrate solutions as functions of uranium concentration, thorium concentration and nitric acid normality is derived; W=1.0-0.3580 C_u-0.4538 C_Th-0.0307H⁺ where W, C_u, C_Th, and H⁺ stand for water content(g/cc), uranium concentration (g/cc), thorium concentration(g/cc), and nitric acid normality, respectively. Water contents of the mixed uranyl nitrate-thorium nitrate solutions are calculated by using the empirical formular, and compared with the values calculated by Bouly's equation in which an additional data, solution density, is required. The two results show good agreements within 2.7%. (Author)

[en] Published in summary form only

No abstract available

No abstract available

No abstract available

[en] Vapor pressure osmometry was used to measure osmotic coefficients of water for thorium nitrate solutions at 25, 37, and 50^oC and at molalities up to 0.2 mol·kg^-1. The data were fitted to three- and four-parameter equations containing limiting-law terms for a 4:1 electrolyte. The variation of the osmotic coefficients as a function of temperature was found to be small. The results are compared to published values for the osmotic coefficients. (author)

[en] Polarographic behaviour of Th(IV) has been studied in 0.10 M NaClO₄ and at pH 4.6, in the presence of some ionic and non-ionic surfactants, viz., Lauryl pyridinium chloride (LPC), Cetyl pyridinium chloride (CPC), Sodium lauryl sulphate (SLS), Dedecyl benzene sulphonate (DBS), Dioctyl sodium sulphosuccinate (DSSS), Ethyl digol and Triton X-100. The electrode reaction is found to be diffusion-controlled and irreversible. The kinetic parameters, αn/sub a/ and k/sub f,h/⁰ of the electrode reaction have been calculated by Koutecky's treatment. The effect of increasing concentrations of the surfactants on the kinetics of the electrode reaction of Th(IV), beyond the stage where maximum is just suppressed has been discussed in terms of the values of αn/sub a/ and k/sub f,h/⁰. (author)