X‐ray fluorescence determination of major elements in ferromanganese nodules

Abstract

In this article, the X‐ray fluorescence technique is proposed for the quantitative determination of major elements in ferromanganese nodules and crusts, which is a necessary stage of the oceanic ferromanganese deposits investigation and development. The research was performed using a wavelength‐dispersive spectrometer S4 Pioneer (Bruker AXS, Germany). Certified reference materials of ferromanganese nodules, cobalt‐bearing ferromanganese crusts and pelagic sediments were dried and prepared by two different techniques: the pressing of powder samples on a boric acid substrate and the homogenization by fusion with lithium tetraborate in an electric furnace at 1050°C. For each sample preparation technique, different forms of calibration curves (linear or quadratic) and methods of matrix effect correction (fundamental parameters or empirical intensities coefficients) were examined. The uncertainty of the proposed technique was assessed by analyzing the certified reference material FeMn‐1 and by comparison with the atomic absorption spectrometry, flame photometry and spectrophotometry results. Analysis of both fused beads and pressed pellets provides a quantitative determination of the major elements in the oceanic ferromanganese nodules.

New Approach for Direct Determination of Manganese Valence State in Ferromanganese Nodules by X-ray Fluorescence Spectrometry

“…For the validation of the proposed XRF technique, 15 samples of oceanic Co-bearing ferromanganese crusts collected on the Govorov and Kotzebue Guyots (Magellan Seamounts, Pacific Ocean) were studied. The content of Mn total was determined by the XRF method [17] and varied from 16.5 to 26.0 wt.%. Average manganese valence state was cal-…”

“…For the validation of the proposed XRF technique, 15 samples of oceanic Co-bearing ferromanganese crusts collected on the Govorov and Kotzebue Guyots (Magellan Seamounts, Pacific Ocean) were studied. The content of Mn total was determined by the XRF method [17] and varied from 16.5 to 26.0 wt.%. Average manganese valence state was calculated from the volumetric results of MnO 2 determination and XRF results of Mn total determination using Equation (2), as well as directly determined by the proposed XRF technique using selected analytical parameters.…”

“…The X-ray fluorescence (XRF) method is widely used for the analysis of geological objects, including ferromanganese nodules and crusts [15][16][17]. Currently, the XRF method allows us not only to determine the total content of an element, but also to evaluate the forms of transition elements, including iron and manganese, based on the dependence of spectral lines intensities on the valence state of an element [18][19][20].…”