TY - JOUR A1 - Matschat, Ralf A1 - Haßler, J. A1 - Traub, Heike A1 - Dette, Angelika T1 - Multielement trace determination in SiC powders: assessment of interlaboratory comparisons aimed at the validation and standardization of analytical procedures with direct solid sampling based on ETV ICP OES and DC arc OES N2 - The members of the committee NMP 264 Chemical analysis of non-oxidic raw and basic materials of the German Standards Institute (DIN) have organized two interlaboratory comparisons for multielement determination of trace elements in silicon carbide (SiC) powders via direct solid sampling methods. One of the interlaboratory comparisons was based on the application of inductively coupled plasma optical emission spectrometry with electrothermal vaporization (ETV ICP OES), and the other on the application of optical emission spectrometry with direct current arc (DC arc OES). The interlaboratory comparisons were organized and performed in the framework of the development of two standards related to the determination of mass fractions of metallic impurities in powders and grain sizes of ceramic raw and basic materials by both methods. SiC powders were used as typical examples of this category of material. The aim of the interlaboratory comparisons was to determine the repeatability and reproducibility of both analytical methods to be standardized. This was an important contribution to the practical applicability of both draft standards. Eight laboratories participated in the interlaboratory comparison with ETV ICP OES and nine in the interlaboratory comparison with DC arc OES. Ten analytes were investigated by ETV ICP OES and eleven by DC arc OES. Six different SiC powders were used for the calibration. The mass fractions of their relevant trace elements were determined after wet chemical digestion. All participants followed the analytical requirements described in the draft standards. In the calculation process, three of the calibration materials were used successively as analytical samples. This was managed in the following manner: the material that had just been used as the analytical sample was excluded from the calibration, so the five other materials were used to establish the calibration plot. The results from the interlaboratory comparisons were summarized and used to determine the repeatability and the reproducibility (expressed as standard deviations) of both methods. The calculation was carried out according to the related standard. The results are specified and discussed in this paper, as are the optimized analytical conditions determined and used by the authors of this paper. For both methods, the repeatability relative standard deviations were <25%, usually ~10%, and the reproducibility relative standard deviations were <35%, usually ~15%. These results were regarded as satifactory for both methods intended for rapid analysis of materials for which decomposition is difficult and time-consuming. Also described are some results from an interlaboratory comparison used to certify one of the materials that had been previously used for validation in both interlaboratory comparisons. Thirty laboratories (from eight countries) participated in this interlaboratory comparison for certification. As examples, accepted results are shown from laboratories that used ETV ICP OES or DC arc OES and had performed calibrations by using solutions or oxides, respectively. The certified mass fractions of the certified reference materials were also compared with the mass fractions determined in the interlaboratory comparisons performed within the framework of method standardization. Good agreement was found for most of the analytes. KW - Inductively coupled plasma optical emission spectrometry KW - Electrothermal vaporization KW - ETV ICP OES KW - Direct current optical emission spectrometry KW - DC arc OES KW - Direct solid sampling technique KW - Silicon carbide powder KW - Method validation KW - Method standardization KW - Direkte Feststoffanalytik KW - Normung KW - Methodenvalidierung KW - Ringversuche KW - Siliciumcarbid PY - 2005 U6 - https://doi.org/10.1007/s00216-005-3415-x SN - 1618-2642 SN - 1618-2650 VL - 383 IS - 7-8 SP - 1060 EP - 1074 PB - Springer CY - Berlin AN - OPUS4-10890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hassler, J A1 - Matschat, Ralf A1 - Richter, Silke A1 - Barth, P. A1 - Detcheva, A.K. A1 - Waarlo, H.-J. T1 - Determination of 22 trace elements in high-purity copper including Se and Te by ETV-ICP OES using SF6, NF3, CF4 and H2 as chemical modifiers N2 - In supplementary work to the one published earlier, experiments with SF6, NF3, CF4 and H2 as new modifier gases for the matrix studied were performed. Our investigations were continued to improve the described analytical method and to achieve additional insights into the mechanism of analyte release. Our new survey is split in two parts. At first fluorinating modifiers were used to investigate the behaviour of a variety of trace elements (Ag, Al, As, Au, Bi, Cd, Co, Cr, Fe, Mg, Mn, Ni, P, Pb, Sb, Se, Si, Sn, Te, Ti, Zn and Zr). Most of them (exceptions Au, Se, and Te) could be effectively released from the copper matrix by thermo-halogenation reactions and by partial sub-sample evaporation. Using SF6 and NF3 as modifier gases, low limits of quantification (LOQs) were achieved for the 19 well released trace elements (typical ≤0.1 mg kg-1). Most elements (exceptions Ag, Mg, and Ni) could be calibrated by using aqueous calibration solutions without any sample pretreatment. For the trace determination of Se, Te, and Au, a further analytical method of ETV-ICP OES is described in the second part based on thermo-hydrogenation reactions by using a hydrogen/argon mixture as a modifier gas. The determination of Se and Te with very high analytical performance (LOQ < 0.1 mg kg-1) can either be carried out in a second analytical step succeeding the halogenation procedure, or the sub-sample is directly treated with H2 without previous halogenation procedure whereby the sub-sample can either be partially or totally evaporated. In this case some other analytes (Ag, Au, As, Bi, Cd, Fe, Mg, Ni, Pb, Sb, Sn, and Zn) can additionally be quantified simultaneously with Se and Te. KW - Pure Cu material KW - Electrothermal vaporization KW - Optical-emission spectrometry KW - Plasma-mass-spectrometry KW - Atomic-absorption spectrophotometry KW - Graphite-furnace AAS KW - Pure copper KW - Spectrochemical analysis KW - Precise determination KW - Sample introduction KW - Silicon-carbide PY - 2016 U6 - https://doi.org/10.1039/C5JA00240K SN - 0267-9477 SN - 1364-5544 VL - 31 IS - 3 SP - 642 EP - 657 PB - Royal Society of Chemistry CY - London AN - OPUS4-35133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -