n view of the current situation of banned azo dye detection in China, the pretreatment of prohibited azo dyes detection is carried out in the operation described in GB/T1759 - 2006 "determination of prohibited azo dyes in textiles".
Therefore, without affecting the final test results, it is necessary to study a new efficient and accurate pre-processing method.
1 test part
1.1 instruments and reagents
Instrument: GC/MSD (7890A/5975C, Agilent Technology Co., Ltd.); constant temperature water bath oscillator; rotary evaporator;
Reagents (all analytically pure): sodium hydroxide, citric acid, sodium hydroxide and ethyl ether.
The sodium citrate buffer solution (0.06 mol/L, pH= "6") was allocated: 12.526 g citric acid and 6.320 g sodium hydroxide, dissolved in water, and fixed capacity to 1000 mL.
It contains two sodium sulfite solution: 200 mg/mL aqueous solution.
When used, the solid is prepared with two sodium sulfite (content equal to 85%) fresh.
1.2 test method
1.2.1GB/T17592 - 2006 method
1) sample preparation and treatment: according to the regulations of GB18401 2003, the samples are cut into 5 mm * 5 mm pieces and mixed evenly, and 1 g (accurate to 0.01 g) is selected, placed in the reactor, 16 mL is added to the sodium citrate solution at 70 degrees Celsius, the reactor is sealed, and the force is shaken, so that all the samples are soaked in liquid, placed in a constant temperature water bath oscillator at 70 degrees Celsius, and heat preservation at 70 (70 + 2) centigrade min, so that all fabrics are fully wetted.
Open the reactor, add 3 mL to two sodium sulfite solution, and immediately close the shake, then reposition the reactor at (70 + 2) centigrade, holding the heat for 30 min, and then cool it to room temperature at 2 min.
3) extraction and concentration: using glass rods to squeeze the sample into the extraction column, the reaction solution was absorbed into the extraction column for 15 min, and the samples were washed with 80 mL ether for four times. The samples were mixed with ether and sample each time, then the ether solution was poured into the extraction column to control the flow rate, and the ether extract was collected in the flask.
The above cylindrical bottomed flask containing ether extract was placed on a vacuum rotary evaporator, concentrated at low temperature of 35 degrees and reduced to nearly 1 mL, and then the ether nitrogen solution was deactivated by nitrogen slow flow to concentrate near dry.
Post time: 2024-11-12 10:03