Detection of Sulfur Compounds in Light Petroleum Liquids According to ASTM D5623 with the Agilent Dual Plasma Sulfur Chemiluminescence Detector and the Agilent Intuvo 9000 GC

Importance of the Topic

Gasoline and light petroleum liquid processing demands accurate quantification of sulfur compounds to prevent equipment corrosion, catalyst poisoning and to meet environmental regulations. The ASTM D5623 method defines procedures for detecting volatile sulfur species, offering rapid and specific analysis essential for refinery process control and quality assurance.

Objectives and Study Overview

This application note evaluates an Agilent Intuvo 9000 gas chromatograph coupled with an Agilent 8355 dual plasma sulfur chemiluminescence detector. The goals are to analyze 23 discrete sulfur compounds in light petroleum liquids according to ASTM D5623, determine linearity and repeatability over a broad concentration range, establish practical limits of detection, and verify accuracy using NIST standard reference materials.

Experimental Methodology and Used Instrumentation

• Gas Chromatograph: Agilent Intuvo 9000 GC with inert flow path, direct heating, and ferrule-less connections; split/splitless inlet at 300 °C; helium carrier gas; Agilent Intuvo DB-1 column (30 m × 0.32 mm, 1 µm film); temperature program from 40 °C (0.71 min) to 250 °C.
• Sample Handling: Agilent 7693A Automatic Liquid Sampler and 7696A Sample Prep WorkBench; stock sulfur standards prepared in isooctane at ~10 000 ppm and diluted to 0.1–100 ppm; diphenyl sulfide at 10 ppm as internal standard.
• Detector: Agilent 8355 dual plasma sulfur chemiluminescence detector operated at a base temperature of 280 °C and burner temperature of 800 °C; dual hydrogen flows (38 and 8 mL/min), oxidizer at 50 mL/min, ozone flow at 36 mL/min, range 6, data rate 5 Hz.

Main Results and Discussion

Linearity was assessed for 22 analytes from 0.1 to 100 ppm (on-column 0.01–10 ppm) with a 10:1 split, yielding correlation coefficients of 0.997–0.999. Repeatability (five injections) showed average area RSDs of 4.1 % at 0.1 ppm, improving to 2.2 % at 100 ppm. All 23 target peaks eluted within 14 minutes with clear resolution. Practical limits of detection were demonstrated at 2 ppb on-column using a 20 ppb standard mix. Analysis of NIST SRM 2299 and SRM 2298 returned total sulfur values of 14.4 ± 0.6 µg/g and 4.0 ± 0.1 µg/g, respectively, both within certified tolerances, confirming method accuracy.

Benefits and Practical Application

By combining the Intuvo 9000 GC’s compact, low-maintenance design with the 8355 SCD’s species-specific, linear response, laboratories can achieve rapid sulfur profiling without individual response factor calibration. The system’s inert flow path minimizes sample loss, and splitless operation down to low ppb levels supports trace analysis in gasoline and related matrices.

Future Trends and Opportunities

Advances in GC microinstrumentation and integrated automation will further reduce analysis time and sample handling errors. Coupling sulfur-selective detection with real-time data processing and laboratory information management systems can enhance process feedback. Emerging regulations on ultra-low sulfur fuels may drive adoption of even lower detection limits and more robust field-deployable systems.

Conclusion

The Agilent Intuvo 9000 GC with the 8355 dual plasma sulfur chemiluminescence detector delivers reliable, linear, and sensitive analysis of volatile sulfur compounds in light petroleum liquids per ASTM D5623. With detection down to 2 ppb, excellent repeatability and strong agreement with NIST reference materials, the platform addresses both regulatory and operational needs in refinery and petrochemical quality control.

Reference

1. ASTM D5623: Standard test method for sulfur compounds in light petroleum liquids by gas chromatography and sulfur selective detection.
2. Veeneman R.; Smith A. Detection of Sulfur Compounds in Light Petroleum Liquids According to ASTM D5623 with an Agilent Dual Plasma Sulfur Chemiluminescence Detector, Application Note 5991-6577EN, Agilent Technologies, 2016.