Abstract:Triphenyl phosphate (TPP) contained in waste liquid crystal displays (LCDs) is a typical phosphorus-based non-halogenated flame retardant with the advantages of high stability, low volatility, low smoke and low toxicity during decomposition. The microwave extraction technique was used to extract TPP from waste LCD polarizing film, and the effects of material-liquid ratio, extraction temperature, extraction time and extractant type on extraction effect were investigated. A standard detection and analysis method for TPP based on gas chromatography-mass spectrometry (GC-MS) was established. The results of GC-MS analysis show that the linear correlation coefficients of TPP reach up to 0.999 6 in the range of 0.5—10 mg/L with good linearity, and the lower limit of detection is 0.51 mg/L. The average recoveries of the method ranges from 97.33% to 101.00% with the relative standard deviations (RSDs) ranging from 2.06% to 2.70%, which can satisfy the requirements of the detection of TPP extraction process in waste LCDs. The microwave extraction results show that TPP extraction rate is 95.20%—96.32% under the optimum conditions including acetone as the extractant, material-liquid ratio of 1︰50, extraction temperature of 55 ℃, extraction time of 20 min, and power of 250 W. This study provides theoretical basis and practical experience for environmentally friendly and efficient recycling of waste LCD.