Effect of pretreatment on the determination of metal content in a natural barite mineral
Two pretreatment methods (Liquid- Liquid Extraction Method, LLEM and Wet Digestion Method,WDM) of samples prior to Atomic Absorption Spectroscopy analysis for metal content were investigated for optimum yield using Atomic Absorption Spectrometry (AAS) on three barite samples. The range of concentration of the fifteen metals by LLEM was 0.25±0.11 – 3,760± 9.59mg/kg and that of WDM was 0.85±0.15 - 3,585± 11.85mg/kg. Some metals were detected by LLEM which were not detected by WDM probably due to evaporative losses. Although, WDM led to the quantitative determination of more metals than LLEM but LLEM led to the determination of the highest concentration of barium, the chief metal in barite which is used in drilling mud. However, there was no statistically significant difference in the metal concentration of the samples in the two methods of pretreatment. Therefore, for solid minerals like barite, a complementary use of the two methods is advised.
Keywords: Weight digestion method, Liquid- liquid extraction method, Nasarawa State, Barite, Atomic absorption spectroscopy, metals