Analysis of clinker and cement

Importance of the topic

Cement and clinker characterization is essential for ensuring consistent product quality, process optimization and compliance with industry standards. Rapid, precise elemental analysis supports formulation control and reduces production downtime.

Objectives and overview of the study

This application note evaluates the performance of the Thermo Scientific ARL OPTIM’X WDXRF sequential spectrometer for routine analysis of major and minor oxides in clinker and cement. The goal is to demonstrate reliable quantification in less than two minutes at a power setting of 200 W.

Methodology and sample preparation

Samples of clinker and cement were ground to under 50 µm to minimize particle size effects. The fine powders were pressed into pellets at 20 tons using a steel ring or boric acid support for mechanical stability. Calibration employed NIST-certified reference materials spanning concentration ranges typical of cement oxides, with multivariable regression used to build calibration curves and calculate standard errors of estimate (SEE). Measurement times were set at 10 seconds per element and 20 seconds for MgO, resulting in a total analysis time of approximately 120 seconds.

Used instrumentation

• Thermo Scientific ARL OPTIM’X WDXRF sequential spectrometer (200 W Rh anode X-ray tube, SmartGonio WDXRF optic covering elements O to Am)
• OXSAS analytical software running under Windows 10 for multivariable regression and data processing

Main results and discussion

Calibration curves for key oxides (CaO, SiO₂, Al₂O₃, Fe₂O₃, MgO, SO₃, Na₂O, K₂O, TiO₂, P₂O₅, Mn₂O₃) exhibited SEE values below 0.5 % across full concentration ranges and detection limits sufficient for trace analysis of light elements. Short-term repeatability over 10 runs showed relative standard deviations meeting or exceeding typical industry specifications. A long-term test of 178 consecutive analyses also maintained RSDs below 0.1 % for most oxides, confirming excellent instrument stability and reproducibility.

Benefits and practical applications

The ARL OPTIM’X WDXRF workflow combines minimal sample preparation with high throughput, enabling turnaround times under two minutes without external cooling or extensive maintenance. Its spectral resolution and stability facilitate accurate analysis of both major components and trace elements, supporting quality control in cement production, raw material screening and compliance testing.

Future trends and applications

Advances may include further reduction of measurement times through optimized counting protocols, integration of inline or at-line sampling for real-time process control and enhanced software algorithms for automated drift correction. Emerging demands in sustainability and material innovation will drive the adoption of rapid, multi-element analysis in cement research and production.

Conclusion

The Thermo Scientific ARL OPTIM’X WDXRF sequential spectrometer delivers fast, precise and robust analysis of cement and clinker oxides. With straightforward sample preparation, reliable calibration and excellent repeatability, it meets the requirements of modern cement laboratories seeking high throughput and quality assurance.