32 3 2011 3 ENVIRONMENTAL SCIENCE Vol 32 No 3 Mar 2011 1 2 1* 1 3 2 1 100101 2 430070 3 100089 3 95 2% ~ 98 2% 99 2% ~ 101 3% 60 mg / kg 12 6% ~ 37 6% X508 A 0250-3301 2011 03-0842-07 Comparative Study on Determinations of BTEX in Soils from Industrial Contaminated Sites MA Dong 1 2 LIAO Xiao-yong 1 YAN Xiu-lan 1 JIN Jing-hua 3 TU Shu-xin 2 1 Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China 2 College of Resources and Environment Huazhong Agricultural University Wuhan 430070 China 3 Environmental Protection Research Institute of Light Industry Beijing 100089 China Abstract In order to ascertain BTEX measurements of soils from industrial contaminated sites static headspace purge-and-trap and solid phase microextraction SPME combined gas chromatography were selected to determine BTEX in the soils This method of SPME could not be used to analyze BTEX isomers in soils from highly contaminated sites because the high concentration of organic contaminants eroded the SPME probe head The recoveries for added standard ranged from 95 2% -98 2% for static headspace-gc and 99 2% -101 3% for purge-and-trap-gc When the soil samples contained low concentrations of BTEX < 60 mg / kg the concentration determined by purge-and-trap-gc was 12 6% -37 6% higher than the value from static headspace-gc For soil samples containing high concentrations of BTEX the static headspace-gc result was higher than that from purge-and-trap-gc The correlation trend lines of individual BTEX isomers to total BTEX were similar for both static headspace-gc and purge-and-trap-gc results Key words contaminated site soil BTEX static headspace purge-and-trap BTEX 1 ~ 3 8 9 - - 3 8 20 70 BTEX 10 11 GC- < 1 mg / kg MS 4 ~ 6 7 2010-06-05 2010-09-01 D08040900360803 PXM2010-178203-096006 1985 ~ E-mail madong@ igsnrr ac cn * E-mail liaoxy@ igsnrr ac cn
3 843 4 1 2 mg / kg 6 BTEX Supelco 6 1 13 - BTEX GC-2010 FID 1 DB-5 30m 0 25mm 0 25μm O I eclipse 4660 1 3 1 1 2 3 USEPA5035 1996 40 ml 2 10 ml 1 4 5 g EXCEL SPSS Table 1 1 1 Selected physical and chemical properties of benzene toluene ethyl benzene and xylene isomers C 6 H 6 C 6 H 5 CH 3 C 6 H 5 C 2 H 5 C 6 H 4 CH 3 2 C 6 H 4 CH 3 2 C 6 H 4 CH 3 2 78 1 92 1 106 2 106 2 106 2 106 2 1 01 10 5 Pa / 80 1 110 6 136 2 144 0 139 3 138 0 20 / g cm - 3 0 8765 0 8669 0 867 0 8802 0 8842 0 8611 25 / kpa 10 1 ~ 13 1 3 6 ~ 4 0 1 3 0 9 1 1 ~ 1 2 1 2 25 / mg L - 1 1800 347 ~ 707 113 ~ 222 113 ~ 223 122 ~ 223 107 ~ 215 lg K oc 1 1 ~ 2 0 1 9 ~ 2 6 1 9 ~ 3 0 1 7 ~ 2 7 2 0 ~ 2 5 2 1 ~ 2 7 lg K ow 1 6 ~ 2 4 2 1 ~ 3 0 3 1 ~ 3 4 2 8 ~ 3 2 3 1 ~ 3 4 3 1 ~ 3 3 lg BCF 0 5 ~ 1 5 0 2 ~ 3 3 0 7 ~ 2 7 0 8 ~ 2 3 0 8 ~ 2 4 1 2 ~ 2 4 13 1 K oc - K ow - BCF 2 1 Table 2 Process of different measurements of BTEX 50 30 min VOC 0 45 3 5 g 3 5 ml 80 50 μl 10 ml 60 min 5 ml 0 6 ml 250 3 min 200 220 200 220 50 200 220 50 50 3 min 10 / min 3 min 10 / min 3 min 10 / min 100 150 5 min 100 20 / min 160 20 / min 160 1 ml / min 1 ml / min 1 15 1 ml / min 1 15 1 25 2 3 3 1 20 11 min 180 4 min 180 15 min 40 ml / min 2 3
844 32 2 2 1 0 1 μg / L 0 1 mg / L Table 3 95 2% ~ 98 2% 99 2% ~ 101 3% 2 1 1 2 2 2 4 2 1 ~ 3 < 60 mg / kg 12 6% ~ 37 6% 1 15 140 mg / kg 2 1 25 5 6 49 7% 89 1% 3 2 BTEX recoveries of static headspace and purge-and-trap n = 5 / % 99 4 99 8 100 8 101 3 99 2 97 2 98 2 96 9 97 6 95 2 4 / mg kg - 1 Table 4 Total BTEX concentrations of soils by static headspace and purge-and-trap / mg kg - 1 / 1 8 7 12 0 0 727 0 2 15 8 18 2 0 867 7 3 44 9 50 5 0 888 3 4 143 140 1 1 020 5 5 613 409 6 1 496 7 6 783 414 1 1 890 9 Fig 1 1 Chromatography of BTEX 2 > 2 mg / kg 3 10 4% ~ 84 9% 2 3 2 2 6 2 50 mg / kg 1 2
3 845 Fig 2 2 Concentrations of BTEX in soils from the industrial contaminated site < 10 mg / kg 3 1 ~ 3 > 10 mg / kg 57 7% ~ 76 1% 2 4 2 2 3 2 95% < 1 S
846 32 2 > > > 2 2 3 Fig 3 Plots of concentrations of BTEX detected by purge-and-trap vs static headspace
3 847 Rosell 16-9 - / 4 VOCs 1 0 5 ng / g - 4 20 2g 0 02 ~ 1 00 μg / kg 1 64% ~ 123% Zuloaga 15 BETX 2 2 - - J 2009 2 6 D 2007 3 J 10 2008 28 3 276-281 95% ~ 105% 2 0 μg / kg 8 - toluene solid-phase microextraction J 6 5% 89% ~ 103% 0 5ng / g 1 25 4 38-41 -GC / MS - - 4 Llompart M Li K Fingas M Headspace solid phase microextraction HSSPME for the determination of volatile and semivolatile pollutants in soils J Talanta 1999 48 2 451-459 5 Ezquerro O Ortiz G Pons B et al Determination of benzene ethylbenzene and xylenes in soils by multiple headspace 2004 1035 1 17-22 Journal of Chromatography A 6 Esteve-Turrillas F A Armenta S Garrigues S et al Headspacemass spectrometry determination of benzene toluene and the mixture of ethylbenzene and xylene isomers in soil samples using
848 32 chemometrics J Analytica Chimica Acta 2007 587 1 89-96 7 M 14 Test Methods for Evaluating Solid Waste Physical / Chemical 1980 240 Methods S EPA SW-846 method 8260B 3rd edition update 8 BTEX III Office of solid waste and emergency response US J 1998 14 6 18-20 Environmental Protection Agency Washington DC 1996 9-15 Zuloaga O Etxebarria N Fernandez L A Multi-Simplex J 2003 optimization and comparison of different purge-and-trap 42 6 856-860 extractions of volatile organic compounds in soil samples J 10 Analytical Chemical Acta 2000 416 1 43-53 J 2001 14 6 40-42 11 determination of methyl tert-butyl ether its degradation products J 2001 11 2 139-141 and other gasoline additives in soil samples by closed-system 12 Closed-System Purge-and-Trap and Extraction for Volatile Organics in Soil and Waste Samples S EPA Method 5035 Revision 0 US Environmental Protection Agency Washington DC 1996 13 BTEX J 2009 28 8 1647-1654 16 Rosell M Lacorte S Ginebreda A et al Simultaneous purge-and-trap gas chromatography-mass spectrometry J Journal of Chromatography A 2006 1132 1-2 28-38 2010 11 26 2009 2009 87 1 87 76 2 72 7 5 421 5 3 669 3 051 1 450 1 730 1 616 1 509