Determination Of Organic Pollutants In Typical Petrochemicals Wastewater By Gas Chromatography

Triazines, amides herbicides and phenol/acetone are commonly used petrochemical products and widely used. Herbicides and phenol/acetone wastewater are typical recalcitrant petrochemical wastewater. The two kinds of wastewater have complex components, serious water quality fluctuation, and recalcitrant toxic organic pollutants.Therefor, The use of different quality analysis method Full analyzed two types of wastewater, a comprehensive analysis of the quality of wastewater were conducted by different methods, and the results can provide the basis to selection and parameter setting of treatment process, the effect of the removal efficiency of organic pollutants of the wastewater treatment process can be observed, meanwhile timely monitoring of organic pollutants discharged into the environment can be conducted.Based on the UV absorption spectra of two wastewater and three-dimensional fluorescence spectra were analyzed. Test results show that the UV absorption of herbicide wastewater locates between 210~270 nm, in the fluorescent region set of λex/λem=200~320/300~400 nm, producing two strong fluorescence peaks(λex/λem=265/365 nm(b), 275/305 nm(c)) and three weak fluorescence peaks(λex/λem=225/305 nm(a), 285/390 nm(d), 320/375 nm(e)); UV phenol/acetone wastewater absorption wavelength is between 190 and 350 nm, and fluorescence mainly concentrated in the λex/λem=215~300/285~360 nm including a strong fluorescence peaks(λex/λem=215/285nm(a)) and 3 weak fluorescence peaks(λex/λem = 255/280 nm(b), 245/350 nm(c), 300/360 nm(d)).An analytical method for the 9 kinds of volatile organic pollutants in herbicide wastewater was established, which was carried out by Purg &Trap extraction pretreatment and then gas chromatography(GC). The analytical method with GC/FID was optimized, and the best detection condition are as follows: the amount of water samples 5 m L, purge gas flow rate of 80 m L/min, purge time 13 min, analytical flow rate of 200 m L/min, resolution time 3 min, split ratio of 5:1, the inlet temperature of 200℃ etc. The method detection limits range from 0.008 to 0.417μg/L, and the recovery rates were in the range of 80.8%~120.2%.An analytical method for the 23 kinds of semi-volatile organic pollutants in herbicide wastewater was established, which was carried out by LLE extraction pretreatment and then gas chromatography(GC). The analytical method with GC/MSD was optimized, and the best detection condition are as follows: extraction of water sample volume 200 m L, Na Cl dosage of 30 g, under acidic conditions, extracted three times, each extracted 2 min, extraction solvent(methylene chloride) in an amount of 7 m L; nitrogen blowing temperature is 25℃, the flow rate of nitrogen blowing 1200 m L/min; inlet temperature of 240℃; split ratio of 5:1; septum purge flow of 0.6 m L/min; temperament transfer line temperature 280℃; solvent delay 3.25 min. The relative standard deviation was <9.167%; detection limits between0.006~0.48 mg/L; recoveries between 80.0%~120.2%.An analytical method for the 6 kinds of volatile organic pollutants in phenol/acetone wastewater was established, which was carried out by HS extraction pretreatment and then gas chromatography(GC). The analytical method with GC/FID was optimized, and the best detection condition are as follows: Under acidic conditions, the amount of water samples 1 m L, Na Cl 0.5g, equilibration time 30 min, equilibration temperature 70℃, standing time 0 min, split ratio of 10:1, the inlet temperature of 220℃ etc. The method detection limits range from 0.02 to 3.0μg/L, and the recovery rates were in the range of 84.5%~126.4%.An analytical method for the 20 kinds of semi-volatile organic pollutants in phenol/acetone wastewater was established, which was carried out by LLE extraction pretreatment and then gas chromatography(GC). The analytical method with GC/MSD was optimized, and the best detection condition are as follows: extraction of water sample volume 2 m L, Na Cl dosage 3g, under acidic conditions and extracted three times, each time extracting 2 min, extraction solvent(methylene chloride) in an amount of 7 m L; nitrogen blowing temperature 15℃, blowing nitrogen flow rate 1000 m L/min; inlet temperature of 240℃; split ratio of 5:1; septum purge flow of 0.6 m L/min; temperament transfer line temperature 280℃. detection limits between 0.004~0.3 mg/L, and recoveries 86.9%~119.8%.