As per the visual representation of Figure 2 and 3, scandium shows the largest enrichment of all the collected samples, especially in Refinery B; whilst Refinery A and Refinery C contain elevated levels of Scandium as well. Chromium was found to be highly variable amongst the three refineries with the highest relative concentration being recorded in Refinery C. Zinc and Vanadium were found to be at a moderate level throughout all the refineries. Moderate enrichment of nickel was identified in each of the samples collected from the refineries; this is thought to be due to nickel's tendency to associate with iron rich minerals (Swain et al., 2022). Gallium showed a high relative enrichment in Refinery B suggesting that gallium associates strongly with aluminum bearing minerals (Xue et al., 2019), while Molybdenum, Lithium, Cobalt, Antimony and Gold were found to be at very low concentrations. Figure 3 illustrates both neodymium and gadolinium were found to be lower concentrations than scandium in the red mud samples. All the samples show similar distribution indicating that there was limited separation of the light rare earth elements. The distribution of potentially toxic elements is illustrated in Figure 4, where selenium was found to be the most relative enrichment of all the toxic elements evaluated. Refinery B contained the largest amount of selenium; followed by Refinery C and Refinery A. Cadmium was found to be at a moderate level of enrichment and displayed little samples variation. However, Arsenic and mercury were found to be present at low concentrations, indicating that most of the toxic elements in the red mud samples are in trace concentrations. 121
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