Determination Of Thorium In Presence Research Articles

Development of a methodology for the determination of americium and thorium by ICP-AES and their inter-element effect

Due to the scarcity of good quality uranium resources, the growth of nuclear technology in India is dependent on the utilization of the vast thorium resources. Therefore, Advance Heavy Water Reactor is going to acquire significant role in the scenario of Indian nuclear technology, where (Th, Pu)O2 will be utilized as fuel in the outermost ring of the reactor core. This will lead to a complex matrix containing thorium as well as americium, which is formed due to β- decay of plutonium. The amount of americium is dependent on the burn up and the storage time of the Pu based fuels. In the present case, attempt was made to develop a method for the determination of americium as well as thorium by ICP-AES. Two emission lines of americium were identified and calibration curves were established for determination of americium. Though the detection limit of 283.236 nm line (5 ng mL−1) of americium was found to be better than that of 408.930 nm (11 ng mL−1), the former line is significantly interfered by large amount of thorium. Three analytical lines (i.e. 283.242, 283.730 and 401.913 nm) of thorium were identified and calibration curves were established along with their detection limits. It was observed that 283.242 and 401.913 nm line are having similar detection limits (18 and 13 ng mL−1, respectively) which are better than that of 283.730 nm (60 ng mL−1). This can be attributed to the high background of 283.273 nm channel of thorium. The spectral interference study revealed that even small amount of americium has significant contribution on 283.242 nm channel of thorium while the other two channels remain practically unaffected. Considering both these facts, spectral interference and analytical performance (detection limits and sensitivity), it was concluded that 401.913 nm line is the best analytical line out of the three lines for determination of thorium in presence of americium.

Some Properties of Iron(III) Selenite and Its Applications for the Determination of Thorium

Abstract A new inorganic ion exchanger, iron(III) selenite has been synthesized having an Fe:Se ratio of 2:3 and cation exchange capacity of 0.40 meq g−1. It is fairly stable in water and dilute solutions of acids, bases, and salts. Ion distribution studies on twenty one metal ions have been done in water. Iron(III) selenite granules in H+-form have also been used as indicators in the determination of thorium in presence of some rare earth cations using hexacyanoferrate(II) as titrant. On the basis of chemical analysis, pH titrations, thermal and infrared analyses the following scheme for the decomposition of iron(III) selenite has been proposed: 2Fe2O3·3H2SeO3·2H2O\overset140°C→2Fe2O3·3H2SeO3\overset500°C→2Fe2O3.