Analysis of trace elements in kerosene using the Thermo Scientific iCAP 7000 Plus Series ICP-OES

Importance of the Topic

The accurate determination of trace elements in kerosene is critical for ensuring fuel quality, protecting engine components from corrosion and deposit formation, and meeting regulatory standards. Precise analysis supports safety in aviation applications and reliability in industrial uses.

Objectives and Study Overview

This work demonstrates the routine quantification of trace metals in kerosene employing ASTM D7111 via ICP-OES. The goals include method optimization for an organic matrix, assessment of detection limits, and evaluation of spike recoveries to validate performance.

Methodology and Instrumentation

Sample preparation involved dilution of oil-based standards and spiking of kerosene with multi-element solutions. An yttrium internal standard corrected for signal drift. Calibration covered low and high concentration levels. The Thermo Scientific iCAP 7400 Plus Series ICP-OES Radial, equipped with an organics sample introduction kit, was selected for its high matrix tolerance and flexible viewing height.
Used Instrumentation:

• Thermo Scientific iCAP 7400 ICP-OES Radial
• Organics sample introduction kit (V-groove nebulizer, baffled cyclonic spray chamber)
• PremiSolv solvents

Key instrument parameters included a pump speed of 25 rpm, nebulizer gas flow of 0.45 L·min⁻¹, auxiliary gas flow of 1.5 L·min⁻¹, coolant flow of 14 L·min⁻¹, RF power at 1350 W, and a radial viewing height of 10 mm.

Main Results and Discussion

Detection limits achieved single-digit microgram-per-kilogram levels for most elements. Spike recoveries for elements such as Al, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Ag, Ti, V, and Zn ranged between 92 % and 120 %, indicating high accuracy. Potassium and sodium spikes showed recoveries of 120 % and 117 %, respectively. Unspiked kerosene samples contained element concentrations below detection in nearly all cases.

Benefits and Practical Applications of the Method

The method offers:

• Reliable quantification of trace metals in complex organic matrices
• Low detection limits suitable for regulatory compliance
• Efficient routine analysis with minimal sample preparation
• Reduced spectral interferences via optimized radial viewing height

Future Trends and Potential Applications

Emerging requirements for even lower detection limits in high-wavelength regions may be met by adding an air mass flow controller to the plasma, further minimizing carbon-related interferences. Integration with advanced data processing and automation will streamline quality control in fuel production and environmental monitoring.

Conclusion

The Thermo Scientific iCAP 7400 Plus ICP-OES Radial paired with an organics introduction kit provides a robust, sensitive, and accurate approach for trace element analysis in kerosene. Single-digit µg·kg⁻¹ detection limits and strong spike recoveries demonstrate its suitability for routine fuel quality assessment.

Reference

ASTM D7111 – Standard Test Method for Determination of Trace Elements in Middle Distillate Fuels by ICP-OES