Elemental analysis of marine fuels

Importance of the Topic

Marine fuel oils constitute the majority of fuel consumed by ocean going vessels and contain a variety of elemental contaminants derived from crude oil and refining processes. Monitoring these contaminants is essential to prevent engine corrosion, wear, and environmental impacts.

Objectives and Study Overview

This study evaluates the performance of the ARL OPTIMX wavelength dispersive X ray fluorescence spectrometer for rapid and accurate elemental analysis of heavy marine fuels in compliance with ISO 8217 requirements.

Applied Methodology

Fuel samples are analyzed without dilution by direct loading into polypropylene film sealed cells and measured under helium atmosphere for 120 seconds. The spectrometer employs an Ultra Closely Coupled Optics design and a SmartGonio goniometer for sequential detection of elements from sodium to zinc.

Used Instrumentation

• ARL OPTIMX WDXRF spectrometer with 50 W rhodium target tube and UCCO optics
• SmartGonio optimized goniometer for broad range sequential analysis
• Optional fixed monochromator channels for enhanced sensitivity on selected elements

Main Results and Discussion

The instrument achieved limits of detection well below ISO 8217 thresholds for sulfur, vanadium, nickel and other contaminants, with typical LoDs ranging from 0.6 to 4.2 ppm. Reproducibility testing over two months yielded a 0.44 percent relative standard deviation on a 2100 ppm sulfur sample, demonstrating long term stability without recalibration.

Benefits and Practical Applications

This technique offers minimal sample preparation, rapid throughput, and simultaneous multi element capability, making it ideal for quality control of marine fuels to ensure compliance and prevent equipment damage.

Future Trends and Potential Applications

Upgrading to a 200 W system can further lower detection limits or reduce analysis time by more than half. Future developments may include automated sampling integration and expanded use in refinery and environmental monitoring contexts.

Conclusion

The ARL OPTIMX spectrometer provides a cost effective, reliable and compliant solution for elemental analysis of heavy marine fuels, meeting international standards for sensitivity and reproducibility.

Reference

• International Sustainable Energy Exchange Residual Fuel Oil and Residual Marine Oil 2008
• Jones RL US Patent 5312585 Corrosion inhibition in high temperature environment 1993
• Institut Français du Pétrole Lyon Direction Physique et Analyse Data courtesy Vernaison France 2004