GB/T 47545-2026Determination of chloroform and other halogenated hydrocarbons in detergents - Gas chromatography-mass spectrometry (English PDF)

5.3

g) sequentially. Add 40.0 µL of internal standard intermediate solution (5.7), quickly seal with aluminum cap, vortex evenly, sonicate for 10 min, and then test.

7.1.2 Laundry Detergent Pods Randomly select one laundry detergent pod, weigh it (accurate to 0.1g), and dissolve it in 40 times its volume of water, stirring gently with a glass rod. Weigh the dissolved product.

8.2 g (m2, weighed to

0.01

g) of the liquid was added to 1 g of sodium chloride (5.3) and 40.0 µL of internal standard intermediate solution (5.7) in 20 mL. The sample is placed in a headspace vial, quickly sealed with an aluminum cap, vortexed evenly, and sonicated for 10 minutes before testing.

5.6 Halogenated hydrocarbon standard intermediate solution (

10.0 mg/L). Take appropriate amounts of each haloalkanes standard sample/standard substance (5.4) and dilute with methanol (5.2) to

10.0 mg/L. Store in a sealed bottle at -18°C. Store away from light. Shelf life is 1 month.

5.7 Intermediate solution of internal standard (

50.0 mg/L). Take appropriate amounts of each internal standard (5.5) and dilute with methanol (5.2) to

50.0 mg/L. Store in sealed bottles at -18°C or below, protected from light. Stored, valid for one month.

5.8 Standard and Internal Standard Mixed Series Working Solutions. Take 5 headspace vials, first add 8 mL of water and 1 g of sodium chloride (5.3) to each, then prepare... Add 10.0 µL, 20.0 µL, 40.0 µL, 100 µL, and.200 µL of the intermediate standard solution of haloalkanes (5.6), and then add the intermediate solution of the internal standard for each. 40.0 µL of solution (5.7) was quickly sealed with an aluminum cap and vortexed to mix. The absolute masses of the standard series working solutions were 0.500 µg, 1.00 µg, and... 2.00 µg, 5.00 µg, and 10.0 µg, where the absolute mass of the internal standard is 2.00 µg. Prepare fresh before use.

6.2 Analytical balance, with an accuracy of

0.1 g and

0.1 mg.

6.3 Vortex Oscillator.

6.4 Muffle furnace [temperature controllable (550±5)°C].

6.5 Headspace autosampler.

7.1.1 Products other than laundry detergent pods Weigh

0.2 g (m1, accurate to

0.001

g) of sample into a 20 mL headspace vial, and add 8 mL of water and 1 g of sodium chloride (

7.2 Instrument Conditions

7.2.1 Headspace Reference Conditions The following are the reference conditions.

a) Equilibrium temperature. 80°C;

b) Injection temperature. 180°C;

c) Transmission line temperature. 180°C;

d) Equilibrium time. 30 min;

e) Quantitative loop. 1 mL.

7.2.2 Chromatographic Reference Analysis Conditions The following are the reference conditions.

a) Chromatographic column. DB-624 capillary column (60m × 0.32mm × 1.8µm), or other equivalent performance;

c) Inlet temperature. 180°C;

d) Injection method. split injection, split ratio 10.1;

e) Programmed temperature rise. Initial temperature 40°C, hold for 0 min, increase to 180°C at 5°C/min, increase to.200°C at 20°C/min, hold 5 minutes.

7.2.3 Mass spectrometry reference analysis conditions The following are the reference conditions.

a) Ion source temperature 230°C;

b) Transmission line temperature 220°C;

7.3 Measurement

7.3.1 Qualitative determination Perform sample determination according to the instrument conditions in 7.2.If the ion chromatographic peaks of the sample solution and the standard appear at the same retention time, and Furthermore, the mass-to-charge ratio of the corresponding mass spectrometry fragment ions is consistent with that of the standard, and their abundance ratio should conform to the requirements of Table 1 compared with the standard sample (5.4). Therefore, it is judged that... The sample contains the corresponding analyte.

7.3.2 Quantitative determination Sample measurements were performed according to the instrument conditions described in 7.2, with the standard working curve solution (5.8) measured from low to high concentrations. The ratio of the mass concentration of the target analyte to its corresponding internal standard is plotted on the x-axis, and the ratio of the peak area of the target analyte to its corresponding internal standard is plotted on the y-axis. Working curve. Based on the peak area ratio, find the mass ratio of the corresponding components from the standard curve and calculate the content of each halogenated hydrocarbon in the sample. Ensure the sample... If the content of halogenated hydrocarbons in the sample bottle is within the range of the standard curve, and the test result exceeds the linear range of the standard curve, the sample size should be reduced and the sample should be weighed again. Measurement.

7.4 Blank Test Except for not weighing the sample, perform blank operations according to steps