Improvement and modification of energy-dispersive X-ray fluorescence method for the determination of metal elements in cement leachates: A chemometric approach

摘要

A modification of an analytical procedure for the energy-dispersiveX-ray fluorescence (EDXRF) quantification of ten chemical elements (As, Ba,Cd, Co, Cr, Cu, Mo, Ni, Pb and Zn) in the leachates obtained from cementbinders was developed. Twenty-nine testing samples were used in the experiment. All samples were based on Portland cement. Fly ash of different origin,zeolite and bentonite were employed as mineral additives in the cement binders. Distilled water was used as the leachate. Validation of the modifiedEDXRF procedure was conducted in terms of limits of detection and quantification, working range, linearity, selectivity, precision, trueness, and robustness.Traceability of the procedure was established using certified reference materials. Uncertainty of measurement was confirmed via an “in-house” laboratoryvalidation approach. The expanded uncertainties for the ten analysed elementswere obtained for the entire working range of the EDXRF method. Robustnessof the modified EDXRF procedure was assessed by means of a chemometricin-house approach. The results obtained by the modified X-ray fluorescencemethod were additionally correlated to those acquired by inductively coupledplasma optical emission spectrometry to confirm that EDXRF could be used asan effective and reliable alternative method for analysis of cement leachates.