Analysis of fatty acid methyl esters with high accuracy and reliability : I. Optimization of flame-ionization detectors with respect to linearity

Abstract The effective linear range of a flame-ionization detector was increased by operating at a higher oxygen hydrogen flow-rate than that required for optimum sensitivity. Evidence of a “superlinear” resposne was seen at even higher hyrogen flow-rates and at high sample loads. Determination of the “grade” of analysis of a mixture which simulated coconut oil methyl esters was shown to be a rapid and simple technique for routinely checking that detector linearity is optimized. Under these conditions, excellent quantitative results were obtained for the mixture over a wide range of analyte concentrations. The value of the Ackman and Sipos theoretical response factor was confirmed.

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