Determination of uranium contents in rock samples from Kakul phosphate deposit, Abbotabad (Pakistan), using fission-track technique

Abstract

Some times high uranium contents are present in the phosphate rocks used for the manufacturing of fertilizer. In view of the harmful effects on human health due to the processing and use of such fertilizers in agriculture, it is important to analyse phosphate rocks for uranium content determination. Ten representative rock samples from Kakul phosphate deposit exposed near Abbotabad, Pakistan which are used for the manufacturing of fertilizers were studied for uranium content determination with the help of fission track and neutron activation analysis techniques. Each sample was split into three parts. The first and second parts (solid slabs and pellets) were subjected to fission track analysis, while the third part was analysed using neutron activation analysis technique for comparison. On the average a uranium content of 37 ppm was found in the phosphate rocks. The results of uranium content determinations with the help of fission track and neutron activation analysis techniques show a remarked resemblance up to ±0.1%. This indicates that the fission track analysis technique of uranium content determination is a reliable method inspite of its simplicity. The uranium content in the Kakul deposits is within the permissible limit allowed for the mining and processing of the phosphate rocks for the manufacturing of fertilizers.