GB/T 23972-2009Determination of alkylphenols and alkylphenol polyethoxylates in textile dyeing and finishing auxiliaries - LC/MS method (English PDF)

3.1 Alkylphenols, AP for short

The molecular structure of alkylphenols is. R-C6H4-OH. The substances that are commonly used in this category are octylphenol (C8H17-C6H4-OH, OP for short) and nonylphenol (C9H19-C6H4-OH, NP for short).

4.1 General provisions

Unless otherwise specified, use only reagents that are identified as analytical reagents, and grade-3 water that is specified in GB/T 6682-2008. The determination of the test results shall be made according to the rounding comparison method of 4.3.3 in GB/T 8170-2008.

4.2 Method summary

For the sample, use methanol as a solvent; use the ultrasonic vibration method to dissolve the alkylphenols and alkylphenol polyethoxylates in the textile dyeing and finishing auxiliaries; filter through a filter membrane; then, use the LC/MS method to select multiple fragment ions from the characteristic ions;

4.3 Instruments and apparatuses

a) HPLC-MS.

4.4 Reagents and solutions

4.5 Determination conditions

4.6 Solution preparation

4.6.1 Preparation of standard solutions

Accurately weigh appropriate amounts of OP, NP, OPEO, and NPEO standards; use methanol to respectively prepare standard stock solutions whose concentration is 1 mg/mL.

4.7 Determination steps

Turn on the liquid chromatography-mass spectrometer to warm up; after the instrument runs stably, first perform a full-scan analysis of the sample; then, compare it with the retention time of the standard sample and the mass spectrum for determination; select a standard test solution of similar concentration; use the selected ions that are specified in Table 2 for measurement. Inject the sample through the autosampler. After the last component had flowed out, use the data processor to process the result.

4.8 Result calculation

The content of alkylphenols or alkylphenol polyethoxylates in textile dyeing and finishing auxiliary products is calculated in mass fraction wi; the value is expressed in (mg/kg); it is calculated according to Formula (1).

5.1 Low detection limit

The lower detection limits of this method for octylphenol, nonylphenol, octylphenol polyethoxylate and nonylphenol polyethoxylate in the sample are 25 mg/kg, 25 mg/kg, 10 mg/kg, 10 mg/kg.

5.3 Precision

The absolute difference between two independent test results, that are gained in the same laboratory, by the same operator, with the same equipment, by the same test method, of which the same test object is tested independently of each other in a short time, is not greater than 20% of the arithmetic mean of the two determination values.