Fast determination of banned azo dyes in textiles

A testing method is developed to rapid determine banned azo dyes in textiles.Effects of testing conditions on the results are investigated and testing parameters are optimized.By adding sodium hydrosulfite,reduction decomposition may disable the banned aromatic amines in citrate solution.Testing procedure is carred out taking ethyl acetate as an extractor for 10 min with mechanical vibration,adding proper amount of sodium sulfate to change the polarity of the solution,and then detecting with GC/MSD.This method can shorten the pretreatment time by more than 50% and save the reagent and material cost by 80%.The recovery of azo dyes is in the range of 22.5%~106% with relative standard deviation less than 10%(n=8).