Uranium metal is inhomogeneously distributed in nature. The recovery of uranium from the earth's crust has been gaining much attention in recent years because of its ever-increasing demand in nuclear technology. It has been determined in different materials viz. ores, rocks, minerals and seawater etc. by several research workers. [1][2][3][4] It occurs in rock materials at minor and trace levels. In meta rhyolite rock, uranium is present at a trace level, and is generally associated with Th, Cs, Fe, Mn, Cu, Si, An analysis of uranium in natural origin (geological) samples is necessary not only in view of its significance for nuclear technology and economic value, but also for its environmental significance. Due to the importance of uranium and other metals, it is desirable to use an analytical technique that is highly sensitive especially at trace levels, specific, precise and yields much elemental information, even for a small sample.Various analytical procedures based on the use of different instrumental techniques have been developed in the past for the determination of uranium and other trace metals in geological samples. 9,10 Atomic absorption spectrometry (AAS) is being increasingly used for the determination of trace amount of metals in ores, minerals and rocks.
11,12Besides, X-ray fluorescence (XRF) analysis, neutron activation analysis (NAA), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and sepctrophotometry have also been applied for such analyses. [13][14][15][16] In the field of the trace analysis of metals, electroanalytical techniques have established themselves as versatile analytical tools for their quick and precise determination. With the development of several advanced electroanalytical techniques, such as differential pulse polarography (DPP), differential pulse anodic stripping voltammetry (DPASV) and adsorptive stripping voltammetry etc., problems related to the simultaneous multielemental determination of metals in different origin samples including geological samples have been simplified. 17,18 The sensitivity of anodic stripping voltammetry has been greatly improved by using a thin mercury film on a glassy carbon fiber electrode 19 and a gold film electrode. 20 Currently, voltammetry and related techniques have emerged as powerful tools for the rapid and simultaneous qualitative and quantitative determination of trace metals in a variety of samples of biological, environmental, metallurgical, industrial and geological origin.
21-25The present paper deals with the application of DCP, DPP and DPASV for the trace analysis of metals in meta rhyolite rock samples. Special attention was paid to the uranium content of the sample. The voltammetric results were compared with those obtained using AAS and XRF methods.
Experimental
SampleThe meta rhyolite rock sample was collected from Ghatwari village near Kherli Bazar area, located 21 km north east of Multai Tehsil, Betul District, (M. P.) India.
ApparatusPolarographic and voltammetric measurements were made on an Elico (Indi...
