Affiliations: Department of Chemistry, University of Rajshahi,
Rajshahi 6205, Bangladesh | Department of Chemical Technology and Polymer
Sciences, Shahjalal University of Science and Technology, Sylhet 3114,
Bangladesh
Abstract: A simple, rapid, and reproducible method is described employing
solid-phase extraction (SPE) using dichloromethane followed by gas
chromatography (GC) with flame ionization detection (FID) for determination of
volatile organic compound (VOC) from the Buriganga River water of Bangladesh.
The method was applied to detect the benzene, toluene, ethylbenzene, xylene and
cumene (BTEXC) in the sample collected from the surface or 15 cm depth of
water. Two-hundred ml of n-hexane-pretreated and filtered water samples were
applied directly to a C_{18} SPE column. BTEXC were
extracted with dichloromethane and average concentrations were obtained as
0.104 to 0.372 μg/ml. The highest concentration of benzene was found as
0.372 μg/ml with a relative standard deviation (RSD) of 6.2%, and cumene was
not detected. Factors influencing SPE e.g., adsorbent types, sample load
volume, eluting solvent, headspace and temperatures, were investigated. A
cartridge containing a C_{18} adsorbent and using
dichloromethane gave better performance for extraction of BTEXC from
water.Average recoveries exceeding 90% could be achieved for cumene at 4°C
with a 2.7% RSD.
Keywords: solid-phase extraction, river water, environmental aalysis, VOC recoveries
