Behavior of redox - sensitive elements (Ti, As, V and Fe) in a clay pit samples with and without Al – normalization
Natural clay minerals, because of their physical and chemical characteristics are good adsorbents of metals. Among metals we often investigate heavy metals, but redox-sensitive metals are getting more and more attention. Redox-sensitive elements were measured in clay pit samples from clay mine in Bosnia and Herzegovina. For the purpose of analysis, a 23 m deep clay pit core sample was taken. From this sample 45 clay pit subsamples from different depths were used. The pH, electrical conductivity (EC), oxidation-reduction potential (ORP) and redox-sensitive elements content were measured. Amounts of redox-sensitive metals and aluminum were measured with an ICP-OES instrument. For statistical evaluation, maximum, minimum, average, median, correlation, correlation applying Al normalization and clr transformation were calculated. When justified PCA analysis was performed. The results are showing acidic pH, and oxidative ORP. The EC varied significantly through the sediment. The element concentrations lie in the sequence: Fe>Ti>V>As. There is a significant change in correlations with and without Al-normalization. The highest difference in was found in case of titanium and vanadium (r value ranging from -0.553 to 0.835). Correlations and PCA after clr transformation showed mainly strong negative correlations, meaning that redox sensitive elements behave differently in clay samples. Supplementary material: https://doi.org/10.6084/m9.figshare.c.7014329