Sulfur Analyzer Nexis GC-2030PFPD2 GC-2014PFPD2

Significance of the topic

Determining sulfur compounds in gasoline is essential for environmental protection, regulatory compliance and equipment longevity. Sulfur species such as hydrogen sulfide and mercaptans can poison catalysts, corrode engine components and increase emissions of sulfur oxides, making reliable analytical methods crucial in fuel quality control and process optimization.

Objectives and Study Overview

The primary goal is to quantify key sulfide species in gasoline using capillary gas chromatography combined with a pulsed flame photometric detector (PFPD). The method follows ASTM-D6228 guidelines, targeting compounds from low concentrations (0.05 ppmV) up to 100 ppmV and covering hydrogen sulfide, carbonyl sulfide, various mercaptans and carbon disulfide.

Methodology

The procedure employs a split/splitless injection port for sample introduction onto a capillary column. Separation is achieved under optimized temperature programming, and the PFPD provides sulfur-selective detection. Equimolar response simplifies quantification of unknown mixtures. Detection limits and linearity are confirmed across the specified concentration range.

Used Instrumentation

• Nexis GC-2030PFPD2 or GC-2014PFPD2 system
• Split/splitless injector with inert sample lines
• Capillary GC column appropriate for light petroleum matrices
• Pulsed flame photometric detector optimized for sulfur
• LabSolutions GC workstation software for data acquisition and processing

Main Results and Discussion

Chromatograms demonstrate clear baseline separation of eight sulfur species, including H2S, COS, MeSH, EtSH, DMS, CS2, PrSH and BuSH. The PFPD response was linear from 0.05 to 100 ppmV for all analytes. Equimolar detection allowed consistent quantification without extensive individual calibration curves. The inert sample path minimized adsorption and sample carryover.

Benefits and Practical Applications

• High selectivity and sensitivity for sulfur compounds in complex fuel matrices
• Equimolar detector response simplifies calibration effort
• Low detection limits enable trace analysis and regulatory compliance
• Inert sample lines reduce analyte loss and improve reproducibility

Future Trends and Opportunities

Advances may include faster capillary columns, miniaturized and portable GC-PFPD systems for on-site monitoring, and coupling with mass spectrometry for enhanced structural identification. Integration with automated sampling and real-time process control will further streamline fuel quality management.

Conclusion

The described GC-PFPD method offers a robust, sensitive and selective approach for quantifying a range of sulfur compounds in gasoline. It meets industry standards, delivers reliable results across a broad concentration range and supports quality assurance in petroleum analysis.

References

1. ASTM D6228 standard test method for determination of sulfur compounds in light petroleum liquids by GC-PFPD.
2. Shimadzu Corporation. System Gas Chromatograph Sulfur Analyzer; SGC-ADS-0010A; First Edition November 2017.