Fast Analysis of the Florida TRPH C8–C40 Standard Using Conventional GC Instrumentation

Importance of the Topic

Rapid and reliable quantification of total recoverable petroleum hydrocarbons in environmental and industrial contexts supports compliance, monitoring and quality control. Reducing chromatographic run times increases sample throughput and lowers operational costs without affecting analytical performance.

Objectives and Study Overview

This study demonstrates the transfer of a Florida TRPH C8–C40 standard analysis from a conventional 30 m × 0.25 mm × 0.25 µm GC column to a 20 m × 0.15 mm × 0.15 µm Thermo Scientific TraceGOLD TG-1MS Fast GC column. The aim is to compare analysis speed, separation quality and reproducibility under optimized conditions.

Instrumentation Used

• GC system: Thermo Scientific TRACE GC Ultra with flame ionization detector
• Columns: standard 100% dimethylpolysiloxane 30 m × 0.25 mm × 0.25 µm and TraceGOLD TG-1MS 20 m × 0.15 mm × 0.15 µm
• Injector: Split/Splitless with BTO septum and Split FocusLiner for 50 mm needle
• Carrier gas: Helium at constant flow
• Autosampler: Thermo Scientific TriPlus fixed needle syringe
• Software: Xcalibur for data acquisition and processing

Methodology

Three methods were evaluated:

• Standard: 30 m × 0.25 mm × 0.25 μm column, 1.2 mL/min, 10 °C/min ramp, 41 min run time
• Fast: 20 m × 0.15 mm × 0.15 μm column, 0.6 mL/min, 15 °C/min ramp, 27.6 min run time
• Faster: same fast column at 1.0 mL/min, 20 °C/min ramp, 21.5 min run time

Phase ratio and temperature gradient equations were applied to maintain equivalent separation conditions during method transfer.

Main Results and Discussion

The fast method achieved a 21 % reduction in analysis time with an 18 % gain in resolution. Increasing linear velocity further delivered a total run time reduction of 40 % versus the standard method, while preserving baseline separation of C8–C40 analytes. Column head pressures rose from 201 to 451 kPa but remained within the 1000 kPa limit of conventional GC systems. Six replicate injections showed retention time RSDs below 0.15 % for all components.

Benefits and Practical Applications

• Improved throughput for environmental and quality control laboratories
• Lower solvent and energy usage per analysis
• Straightforward method transfer without hardware modifications

Future Trends and Possibilities

Further improvements may include adoption of sub-0.1 mm i.d. columns, integration with mass spectrometric detection for enhanced identification, higher pressure GC systems for ultra-fast separations, and software tools for automated method translation.

Conclusion

Transferring the Florida TRPH C8–C40 analysis to a fast GC column significantly reduces run times by up to 40 % with no compromise in resolution or reproducibility, offering a powerful approach to boost efficiency on conventional GC platforms.