TOOLS AND TECHNIQUES THAT KEEP YOU PRODUCTIVE, PROFITABLE, AND COMPLIANT

Significance of the Topic

The diverse Application Notes from Agilent’s Information Pipeline illustrate the critical role of advanced analytical techniques in the energy, chemical and materials industries. Precise gas chromatographic and liquid chromatographic methods ensure regulatory compliance, process optimization, product quality and environmental stewardship. Rapid, sensitive detection of hydrocarbons, permanent gases, sulfur species, ethanol content and polymer additives supports fuel specification, refinery control, petrochemical monitoring and polymer quality assurance.

Aims and Overview of the Collection

This compendium presents selected Agilent Application Notes covering:

• Rapid refinery gas analysis (RGA) by parallel GC with three simultaneous detectors (FID and dual TCDs)
• Simulated distillation of hydrocarbons and sulfur by GC with chemiluminescence detection
• Automated sample preparation for simulated distillation standards using the 7693A autosampler and tray
• Trace impurity analysis in benzene by GC–FID
• Sulfur compound measurement in natural gas by GC–dual plasma SCD
• Quantification of methanol and ethanol in denatured fuel ethanol by GC–FID
• Rapid LC–UV/VIS separation of phenolic antioxidants and polymer slip agents

Methodology and Instrumentation

All workflows employ Agilent’s GC or LC platforms with full electronic pneumatics and controlled temperature programming. Key configurations include:

• Agilent 7890A GC with split/splitless inlets, capillary flow technology, multi-column valve manifolds, backflushing, low thermal mass ovens (LTM) and multilane 7693A autosamplers
• Agilent 7820A GC for benzene impurity analysis with one-column injection and FID
• Agilent 355 dual plasma sulfur chemiluminescence detector (SCD) for selective sulfur detection at ppb levels
• On-line dilutor and inert sampling valves for low-level gas standards
• Agilent 1200 Series Rapid Resolution LC system with narrow-bore UHPLC columns and diode-array UV detection for polymer additives

Main Results and Discussion

• Parallel GC RGA: Complete analysis of C1–C5, C6+ and permanent gases (H₂, O₂, N₂, CO, CO₂) in under 6 minutes with 10–500 ppm detection limits and excellent repeatability (RSD<0.5 %).
• Dual-channel SimDis: Simultaneous hydrocarbon (FID) and sulfur (SCD) boiling-point distributions per ASTM D2887, D7213, D7398 with agreement within ASTM tolerances and booms to C40–C70 fractions.
• Automated SimDis sample prep: 7693A towers and heated tray enable precise dilution, mixing, heating and backflushing for D2887, D7213, D7398 and D6352 without manual handling of CS₂, improving safety and throughput.
• Benzene impurity analysis (ASTM D4492): Single-column GC–FID method resolves C6–C9 non-aromatics, toluene, C8 aromatics and dioxane with RT RSD<0.1 % and area RSD<2 %.
• Sulfur in natural gas (ASTM D5504): DP SCD with on/off valve injection and online dilutor quantifies H₂S, COS, mercaptans and thiophenes down to 1 ppb with stable response over 72 h (RSD<5 %).
• Denatured ethanol (ASTM D5501): 7890A GC–FID method measures methanol at 0.02 wt % and ethanol at 97.8 wt % with splitter linearity across C5–C11 and RSD<1.2 %.
• Polymer additive LC (ASTM D5815, D1996): Rapid SSL-RRLC method on 2.1×50 mm, 1.8 µm C18 column cuts run time to 3 min versus 25 min, resolving seven antioxidants and slip agents at 1 ppm with S/N>50.

Benefits and Practical Applications

The described methods provide:

• High-throughput analysis optimized for routine QC and regulatory compliance
• Reduced analysis time and solvent consumption for cost-effective operations
• Enhanced sensitivity and selectivity for trace-level sulfur and hydrocarbon species
• Automated sample handling for safer workflows and lower operator error
• Proven integration with ChemStation and reporting macros for seamless data management

Future Trends and Opportunities

Advances in chromatography and detection will drive:

• Further miniaturization and acceleration of multi-dimensional separations
• Integration of AI-guided method optimization for rapid deployment
• Expansion of portable GC and FTIR-ATR instruments for field analysis
• Improved sample preparation robotics for fully hands-off laboratories
• Enhanced hyphenated techniques combining GC×GC and high-resolution MS

Conclusions

The Agilent Application Notes demonstrate a suite of robust analytical solutions spanning gas chromatography, sulfur chemiluminescence detection, simulated distillation and rapid LC for a broad range of energy, chemical and materials testing needs. These methods offer exceptional speed, sensitivity and reliability, enabling laboratories to enhance productivity, ensure product quality and maintain regulatory compliance.

References

• ASTM D1945, D1946, D2887, D5504, D5501, D4492, D5815, D1996, D7213, D7398, D6352
• Praxair sulfur standards; Spectrum Quality Standards ethanol calibration
• Agilent Application Briefs and Notes 5989-7438EN, 5990-3237EN, 5990-3548EN, 5989-9234EN, 5989-7807EN, 5990-6650EN