Analysis of platinum group elements with the Thermo Scientific iCAP PRO Series ICP-OES

Importance of the Topic

The platinum group elements (PGEs) are a set of six transition metals valued for their rarity, catalytic activity, and resistance to corrosion. They play critical roles in emissions control, chemical processing, electronics, and jewelry. Analyzing PGEs accurately in complex matrices is essential for quality control and regulatory compliance.

Objectives and Study Overview

This application note evaluates the performance of the Thermo Scientific iCAP PRO XP Duo ICP-OES in quantifying PGEs within high-concentration base-metal matrices. The goal was to achieve accurate, precise analysis without sample separation, leveraging high-resolution optics and robust plasma conditions.

Methodology

Samples simulated digests of solid catalysts (0.25 g into 100 mL of 10% HCl/1% HNO₃). The matrix contained Ni, Cu, Co, Fe, S, Au, and PGEs (Pt, Pd, Rh, Ru). No pre-concentration or separation was required due to the instrument’s full wavelength coverage and resolution. A yttrium internal standard (8 mg/kg) was added. Wavelength selection employed the Fullframe feature of Qtegra ISDS Software, ensuring separation of analyte and matrix lines (e.g., Pd 340.458 nm from Co 340.512 nm).

Instrumentation

• Thermo Scientific iCAP PRO XP Duo ICP-OES with high-resolution Echelle optics and 7th-generation CID detector
• Standard aqueous sample introduction kit and internal standard addition kit
• Teledyne CETAC ASX-560 autosampler

Main Results and Discussion

Instrument detection limits ranged from 0.003 to 0.010 mg/kg, while method detection limits were 0.00009–0.00021 mg/kg. Calibration curves for Au, Pd, Pt, Rh, and Ru were linear up to 10 mg/kg with correlation coefficients >0.999. Recoveries for simulated samples were within 100–102%, demonstrating accuracy in a robust base-metal matrix. Sample throughput was approximately 45 samples per hour, with potential for higher rates using discrete introduction.

Benefits and Practical Applications

• Simultaneous multi-element PGE analysis without matrix separation
• High throughput suitable for manufacturing and quality-control laboratories
• Robust operation in high-concentration matrices with low maintenance
• Accurate quantification at trace and high concentration levels

Future Trends and Potential Applications

Advances in detector technology and software automation will further enhance sensitivity, speed, and data processing. Integration with discrete sample introduction systems and real-time process analytics could broaden applications in catalyst manufacturing, environmental monitoring, and high-throughput screening. Emerging industries may adopt high-resolution ICP-OES for novel PGE-based materials and nanotechnology research.

Conclusion

The Thermo Scientific iCAP PRO XP Duo ICP-OES delivers precise, accurate, and high-throughput analysis of PGEs in complex metal matrices. Its high resolution, robust plasma tolerance, and intuitive software make it an effective tool for diverse analytical and industrial applications.

References

1. USGS, Platinum–Group Metals Statistics and Information.