The method of determination for butyronitrile and isobutyronitrile in the air of workplace by dissolved desorption-gas chromatography / 中华劳动卫生职业病杂志

Objective: To establish a method for the determination of butyronitrile and isobutyronitrile in the air of workplace by gas chromatography. Methods: In March 2020, butyronitrile and isobutyronitrile in the air of workplace was collected by silica gel, eluted with methanol, separated and determined by gas chromatogram with flame ionization detector, the characteristics of determination of nitrile and isobutyronitrile by gas chromatography were analyzed. Results: The limit of detection for butyronitrile and isobutyronitrile was 0.33 μg/ml. The linear range of butyronitrile determined by this method was 1.60-1600.00 μg/ml, y=2.295x-3.480, and the coefficient correlation was 0.99998, and the minimum detection concentration was 0.22 mg/m(3) (collected sample volume was 1.50 L) . The within-run precisions were 2.43%-4.12%, the between-run precisions were 1.72%-3.70%, and the desorption rates were 93.26%-98.41%. The linear range of isobutyronitrile determined by this method was 1.52-1520.00 μg/ml, y=2.208x-0.102, and the coefficient correlation was 0.99998, and the minimum detection concentration was 0.22 mg/m(3) (collected sample volume was 1.50 L) . The within-run precisions were 2.52%-3.22%, the between-run precisions were 1.20%-3.82%, and the desorption rates were 96.85%-102.50%. The sealed samples could be stored at least 10 days at room temperature without significant loss. Conclusion: The method has the advantages of good precision, high sensitivity and simple operation. It is suitable for the simultaneous determination of butyronitrile and isobutyronitrile in the air of workplace.

Determination of 15 kinds of vapor state organic acids in workplace air by dissolved desorption-gas chromatography / 中国职业医学

OBJECTIVE: To establish a method for simultaneous determination of 15 kinds of vapor state organic acids in workplace air by solvent desorption-gas chromatography.METHODS: A total 15 kinds of vapor state organic acids such as acetic acid, propanoic acid, butyric acid and pentanoic acid in the air of workplace were collected by silica gel, eluted with acetone, separated by DB-FFAP capillary chromatograph column, and detected by gas chromatography with flame ionization detection. RESULTS: There was a good linear relationship in the selected range of 15 kinds of organic acids. The coefficient correlation was 0.999 97-0.999 98. The limit of detection of this method was 0.04-0.29 mg/L, and the minimum detection concentration was 0.03-0.19 mg/m~(3 )(collected sample volume was 1.50 L). The average desorption efficiency was 92.9%-98.5%. The within-run and between-run relative standard deviation was 0.3%-1.6% and 1.5%-3.0%, respectively. The samples could be kept for at least 15 days at room temperature. CONCLUSION: The method is simple for operation, with high sensitivity, and good precision, which is suitable for simultaneous determination of 15 kinds of vapor state organic acids in the air of workplace and sites of emergency accident.