Validation of a gas chromatography/thermal conductivity detection method for the determination of the water content of oxygenated solvents

• Published in: Journal of Chromatography A Vol. 1182; no. 1; pp. 113 - 118
• Main Authors: O’Keefe, W.K., Ng, F.T.T., Rempel, G.L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 22-02-2008; Amsterdam; New York: Elsevier; Elsevier
• Subjects: Acetone; Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, Gas - methods; Exact sciences and technology; Gas chromatographic methods; GC/TCD; MIBK; Oxygenated solvents; Reproducibility of Results; Solvents - analysis; Thermal Conductivity; Water - analysis; MIBK; Oxygenated solvents; GC/TCD; Water analysis; Acetone; Validation; Chemical analysis; Thermal conductivity detector; Methyl isobutyl ketone; Gas chromatography; Organic solvent; Water content; Quantitative analysis
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2007.12.044

A gas chromatographic (GC) method for the determination of the water content of acetone solutions containing methyl isobutyl ketone (MIBK) and other by-products of MIBK synthesis was developed and validated. Linearity is demonstrated (
R
2
=
0.9999) over a broad range of water concentrations in acetone ranging from 0.04 to 15.2% (w/w). The quantitation limit (QL) of this technique was found to be 0.346% (w/w) and the detection limit (DL) was estimated to be 13
ppm. Validation of this analytical method's accuracy against a coulometric Karl Fischer titration (KFT) method showed excellent agreement between these two techniques. The GC/TCD method is accurate to within a relative error of 3.49% with respect to the KFT method for water concentration above the QL. However, the analysis of six samples below the QL showed an average relative error of 10.96%. Consequently, the KFT method is recommended for the moisture analysis of samples for water concentrations below 0.35% (w/w). Excellent precision is realized for water concentration above the QL (RSD
≪
0.8%). Good precision (RSD
=
1.1%) was obtained for the sample with the lowest water concentration investigated (0.04%, w/w). Repeatability, robustness and excellent specificity of this technique are demonstrated.