چكيده به لاتين
Abstract:
Nowadays, determination of volatile sulfur compounds because of environmental concerns, as well as assessing the quality of oil products and chemical products, has attracted the attention of many researchers. In this work, firstly a porous support by using anodized aluminum wire was obtained. For this purpose, the variables that affect anodization process such as electrolyte concentration and temperature, anodizing potential and time were optimized and high porous layer was developed that the optimum values for temperature, electrolyte concentration, time and anodizing potential 250C, 3M, 120 min and 15V were achieved, respectively. Characterization of the alumina was generated by anodization has been carried out by scaning electron microscopy (SEM) and adsorption and desorption of nitrogen (BET). Afterward, a thin film of gold using by sputtering method was coated on the porous support. Then, this prepared fiber was used to head space solid phase microextraction for thiophene and 1,2-ethanedithiol as a sulfur compounds in the optimum extraction condition; the extraction time 20 min, extraction temperature 300C in the presence of sodium chloride with concentration of 6%(w/v) that limit of detection for both compounds .84 micrograms per liter were achived. To evaluated the selectivity of prepared fiber for sulfur compounds against other compounds; head space solid phase microextraction of thiophene and 1,2-ethanedithiol was performed in presence of 1-butanol and n-heptane as contaminating agent in extraction which extraction efficiency for 1,2-ethanedithiol and thiophene 95.5 and 93 and for n-heptane and 1-butanol 4 and 17 were obtained respectively. Eventually, the made fiber was used to determine thiophene in real sample gas oil refinery complex matrix that gave 92.4 recovery percentage. Enrichment factor for thiophene and 1,2-ethanedithiol 210 and 231 were obtained, respectively
Keywords: Gas chromatography, Volatile sulfur compounds, Head-space solid phase microextraction, Anodized aluminium wire, Gold coating, High selectivity
