Study of properties of chemically modified samples of halloysite mineral with X-ray fluorescence and X-ray powder diffraction methods

Author-Highlights
• We measured elemental and chemical composition of raw and activated halloysite mineral samples.
• We showed that X-ray techniques allow precise study of changes in the sample composition.
• We describe procedure of activation of the samples by etching them in sulfuric acid.
• We tested ability of halloysite mineral to absorb lead from contaminated water.

Elemental and chemical composition of raw and activated samples of halloysite mineral using wavelength dispersive X-ray fluorescence (WDXRF), total reflection X-ray fluorescence (TXRF) and X-ray powder diffraction (XRPD) methods were determined. As the result, it has been shown that application of the complementary X-ray spectrometry techniques allows very precise observation of changes in composition of halloysite mineral samples caused by its chemical modifications. Sample preparation procedure and usability of the research methods applied are described in details. Procedure of activation of raw halloysite mineral samples by etching them in sulfuric acid of various concentrations has been described and discussed. The ability of the samples to adsorb lead from intentionally contaminated water was tested and confirmed.