Total oxide X-ray analysis with ARL 9900 IntelliPower Series Simultaneous/Sequential X-ray Fluorescence Spectrometers

Importance of the Topic

Wavelength-dispersive X-ray fluorescence (WD-XRF) is a cornerstone technique in analytical chemistry for rapid, precise and non-destructive quantification of oxide materials. Its broad dynamic range, minimal sample preparation and high stability make it indispensable in mineralogy, metallurgy, cement, ceramics and environmental laboratories.

Objectives and Overview

This application note presents the performance of the Thermo Scientific ARL 9900 IntelliPower WD-XRF spectrometer using a general oxide calibration based on fused bead sample preparation. Key goals include evaluating calibration accuracy, limits of detection, sample preparation methods and operational flexibility.

Methodology and Instrumentation

• Instrument: ARL 9900 IntelliPower WD-XRF with simultaneous/sequential goniometer and optional fixed channels.
• Software: Thermo Scientific OXSAS for multivariable regression and matrix correction.
• Sample preparation: Fusion of 0.7 g sample with lithium tetraborate/ metaborate flux (1:11 dilution) on Katanax electric or Vulcan/Fluxana gas fusion unit.
• Calibration: Factory pre-calibration with certified fused standards or on-site calibration using a 24-standard oxide kit.

Main Results and Discussion

• Calibration ranges cover major oxides (Al₂O₃, SiO₂, CaO, Fe₂O₃, MgO, etc.) from ppm to >90 % levels.
• Standard error of estimate (SEE) is typically below 0.3 % for major oxides; for example, Al₂O₃ SEE = 0.16 %, CaO SEE = 0.32 %, SiO₂ SEE = 0.23 %.
• Limits of detection (3σ) in a 100 s analysis vary with power: at 3600 W, CaO ~12 ppm, SiO₂ ~13 ppm, Fe₂O₃ ~12 ppm; at 1200 W, CaO ~20 ppm, SiO₂ ~22 ppm.
• Ignited vs. non-ignited sample prep: Ignition at 1050 °C improves accuracy and protects crucibles from metallic inclusions; LOI values up to 47 % can be corrected automatically.

Benefits and Practical Applications

• High precision and accuracy across a wide concentration range.
• Rapid analysis times (4–40 s per element) and flexible configuration without external water cooling up to 2500 W.
• Automatic LOI correction and robust matrix handling reduce sample prep errors.
• Applicable to raw minerals, industrial oxides, cement, ceramics and metallurgical slags.

Future Trends and Applications

Advances in detector design, integration of fixed channels for simultaneous measurement and AI-driven spectral deconvolution are expected to further accelerate throughput and lower detection limits. Remote monitoring, automated sample handling and cloud-based calibration updates will enhance productivity in high-volume QA/QC environments.

Conclusion

The ARL 9900 IntelliPower WD-XRF spectrometer combined with fused bead sample preparation delivers reliable, high-throughput oxide analysis. Its versatile calibration options, robust hardware design and advanced software make it a valuable tool for diverse analytical laboratories.

References

• Bonvin D., AN41404 “Total oxide X-ray analysis with ARL 9900 IntelliPower Series”, Thermo Fisher Scientific, 2019.