Development of a quantitative method for the analysis of zinc in various ores by spectroscopy

Abstract

Zinc is the most used non-ferrous metal in modern society and it has the major ability to prevent steel from corrosion which has significant positive effects on the economy and environment. Given the vital role of zinc in such applications, the inconsistent results produced necessitated further investigation on the zinc analysis. Inductively coupled plasma optical emission spectroscopy and X-ray fluorescence spectroscopy were used in this study to investigate sample preparation and develop a comparative approach for determining zinc concentrations in various ores. This study emphasised the determination of Zinc from different zinc ores by the conventional and new technology methods, which include X-ray fluorescence spectroscopy, inductively coupled plasma optical emission spectroscopy and X-ray diffractometer techniques. Mineral abundance was shown by analytical data from the x-ray diffractometer including sphalerite, pyrite, dolomite, chalcopyrite and calcite. The X-ray fluorescence spectroscopy data indicated that the elemental compositions had high concentrations ranging from 50 to 0.07% for (Zn, S, Fe, Ca, Cu, Mg and Si) as major elements. Certified reference materials were used to validate the methods and compare the results produced by the two techniques. The instrumental analysis results demonstrated that inductively coupled plasma emission spectroscopy by microwave acid digestion performed better than the X-ray fluorescence spectroscopy pressed pellet approach. The results showed that inductively coupled plasma optical emission spectroscopy is more efficient method for obtaining zinc ore samples. Both techniques achieved good recovery rates ranging from 80 to 120%. Inductively coupled plasma optical emission spectroscopy revealed a higher concentration of zinc ore in the samples investigated than X-ray fluorescence spectroscopy. Microwave acid digestion with inductively coupled plasma optical emission spectroscopy acquired 99.64 and 100.4% whereas the pressed pellet approach with X-ray fluorescence technique obtained 98.89 and 99.22% recoveries. The results of the two techniques were in good agreement; however, the inductively coupled plasma optical emission spectroscopy outperforms the X-ray fluorescence spectroscopy. Overall performance of the methods was satisfactory, demonstrating consistency and reliability in achieving accurate zinc recoveries.