Analytical accuracy of hydrogen measurement using gas chromatography with thermal conductivity detection

Gas chromatography employing a thermal conductivity detector with a nitrogen carrier gas and a molecular sieve 5 Å column is commonly used for the analysis of widely varying hydrogen concentrations. Flow variation of the column, caused by carrier gas adsorption, affects the peak shape and impacts the analytical accuracy. The mechanism and factors affecting the adsorption effect are explored, errors caused by the deviation from the linearity of the detector's response are considered, and practical advice is given for improving the analytical accuracy.