Analytical ad Retention Index of 61 Components of Organic Solvents - Using InertCap 5

Significance of the Topic

Gas chromatography retention indices are essential for matching unknown compounds to reference data by normalizing their retention times to those of n alkane standards. This approach supports reliable qualitative analysis in fields such as environmental monitoring pharmaceutical development and industrial quality control.

Objectives and Study Overview

This report presents determination of retention indices for sixty one common organic solvents using an InertCap 5 column under both isothermal conditions and temperature programmed analysis. The aim is to expand reference data for solvent identification and to demonstrate linear relationships between retention indices and carbon number.

Methodology and Instrumentation

The analysis was carried out on a gas chromatograph with flame ionization detection. The InertCap 5 capillary column features a 0.25 millimeter internal diameter 60 meter length and 0.25 micrometer film thickness. Helium was used as carrier gas at 160 kilopascals with split injection of 0.1 microliter sample at 240 degrees Celsius. Temperature programming ramped from 40 to 220 degrees Celsius at 5 degrees per minute while isothermal runs were performed at 40 80 120 and 160 degrees Celsius. Retention indices were calculated by linear interpolation between retention times of straight chain alkanes bracketing each analyte.

Key Results and Discussion

Retention indices in temperature programmed analysis ranged from 380 for methanol up to 1072 for m cresol demonstrating a consistent increase with carbon number.
Isothermal results showed slight index variation across temperatures reflecting changes in selectivity at different column temperatures.
Chromatograms confirmed baseline separation of most components and agreement with theoretical alkane based index values.

Benefits and Practical Applications

Using an InertCap 5 column provides reproducible retention index data for solvent libraries facilitating rapid compound identification in complex mixtures. The expanded dataset supports method development in environmental analysis industrial process monitoring and quality assurance laboratories.

Future Trends and Potential Applications

Continued expansion of retention index databases combined with advanced prediction algorithms and machine learning may further enhance automated GC identification workflows. Extending such studies to polar and specialty stationary phases will broaden applicability to diverse analyte classes.

Conclusion

The retention index data for sixty one organic solvents obtained on InertCap 5 confirms the reliability of alkane normalized methods under both isothermal and programmed conditions. This dataset serves as a valuable reference for qualitative gas chromatographic analysis.

References

• GL Sciences Inc GC Technical Note Analytical and Retention Index of 61 Components of Organic Solvents Using InertCap 5