چكيده به لاتين
The BTEXs are volatile monoaromatic hydrocarbons that comprise one of the most ubiquitous and hazardous groups of ambient air pollutants of concern [1] The objective of this research was to develop a simple, low-budget, and accurate method by solid phase nano-extraction (SPNE) for quantification of BTEX in ambient air based on SPNE -GC–FID.
The electrospinning technique was successfully used to create nano-fiber of the polydimethylsiloxane/polyacrylonitrile as a synthesis SPNE coating. Standard 20 mL head-space vials were used for field air sampling and calibration. SPNE experimental conditions, such as extraction time, extraction temperature, desorption time, desorption temperature, were optimized using one-at-time. The optimum conditions were extraction time 40 min, extraction temperature 25ºC desorption time 5 min and desorption temperature 250 ºC Under these conditions, calibration curve in the two range for benzene, toluene 20-1000 µg/m3 and ethylbenzene, xylene 5-1000 µg/m3 are linear with R2= 0.998, 0.997, 0.998 and 0.998, respectively. The repeatability at two concentration levels (50 and 400 µg/m3) was calculated. Relative standard deviation was 10-12%, 9.14-10.7%- 9.33-11.9% for inter-day, intra-day and fiber-to-fiber, respectively. The of detection and limit of quantification were found 0.26-2.86 and 1-9.64 µg/m3. The relative recoveries were obtained from 91-105%. Air samples were collected from the bus station and analyzed by the mentioned method The mean concentration of ethylbenzene and xylene in the air samples were 6 and 8 µg/m3, respectively.
Keywords: Solid phase nanoextraction, Electrospinning, Nanofibers,Polydimethylsiloxane, BTEX compounds, Air pollutant, Gas chromatography
