Distribution of Benzene, Toluene, Ethyl Benzene, Xylene (Btex) and Polynuclear Aromatic Hydrocarbons (PAHs) in Diesel Fuel from Independent Marketers and Bunkering Activities in Nigeria

Abstract

Communication in Physical Sciences 2019, 4(2): 67-73

Authors: Usoro M. Etesin &, Iniobong J. Ogbonna
Received 12 November 2019/Accepted 25 December 

In order to check the quality of diesel fuels distributed in Nigeria, a study was carried out to comparatively assess the distribution of benzene, toluene ethylbenzene and xylene (BTEX) and polyaromatic hydrocarbons (PAHs) in diesel fuels from independent marketers and bunkering activities in Nigeria. Ten diesel fuel samples were collected from each source of the product, extracted
and analyzed using gas chromatograph equipped with flame ionization detector. Diesel fuel from independent marketers indicated the presence of benzene , 830.3 ± 11.26 mg/L ; toluene , 1126.2 ± 20.18 mg/L ; ethyl benzene, 14.17 ± 2.11 mg/L; m,pxylene, 122.7 ± 8.03 mg/L ; o-xylene, 72.28 ± 11.21 mg/L, while diesel fuel from bunkering sources indicated the presence of benzene , 100.6 ± 9.23mg/L ; toluene , 276.6 ± 11.9 mg/L ; ethyl benzene,25.78 ± 3.01 mg/L; m,p-xylene, 27.73 ± 5.01 mg/L ;
o-xylene, 140.3 ± 12.41 mg/L. . Diesel fuel from independent marketers indicated the presence of PAHs including naphthalene, 377.4 ± 17.2 mg/L ; acenaphthalene, 2337.4 ± 21.9 mg/L ; acenaphthene, 849.5 ± 15.1 mg/L ; fluorene, 428.3 ± 9.11 mg/L ; anthracene, 974.9 ± 12.52 mg/L ; phenanthrene, 575.5 ± 16.12 mg/L ; fluoranthrene, 748.6 ± 21.26 mg/L ; pyrene, 988.3 ± 19.28 mg/L ; benzo(c )fluoranthene, 1983,9 ± 30.16 mg/L ; chrysene, 429.9 ± 12.66 mg/L ; benzo(a)anthracene, 108.7 ± 12.09 mg/L ; benzo(a)pyrene, 193.9 ± 16.22mg/L ; indeno(1,2,3,c,d)pyrene, 19.16 ± 1.92 mg/L ; dibenzo(a,h)anthracene, 11.52 ± 1.63 mg/L ;
benzo(g,h,i)perylene, 34.72 ± 2.71 mg/L , while diesel fuel from bunkering source indicated the presence of naphthalene, 6.587 ± 0.32 mg/L ; acenaphthalene, 2941.6 ± 31.71 mg/L ; acenaphthene, 1029.5 ± 29.22 mg/L ; fluorene, 3375.4 ± 27.39 mg/L ; anthracene, 4507.6 ± 37.69mg/L ; phenanthrene, 5982.6 ± 41.66 mg/L ; fluoranthrene, 2944.9 ± 39.22 mg/L ; pyrene, 1623.9 ± 37.79 mg/L ; benzo(c )fluoranthene5419.5 ± 43.12 mg/L ; chrysene, 1096.8 ± 29.61mg/L ;benzo(a)anthracene, 647.5 ± 22.16 mg/L ;
benzo( a)pyrene, 101.2 ± 9.24 mg/L ; indeno(1,2,3,c,d)pyrene, 17.25 ± 1.73 mg/L ; dibenzo(a,h)anthracene, 68.18 ± 8.23 mg/L ;
benzo(g,h,i)perylene, 52.46 ± 7.53 mg/L . Diesel fuel from independent marketers had aromatics contents relatively higher (14.17 – 1126 mg/L) than those from bunkering source (25.78 – 276.0 mg/L), while PAHs contents were relatively higher in bunkering diesel (6.587 – 5982 mg/L) than in diesel fuel from independent marketers (11.52 – 2337 mg/L). Statistical analysis of variance in the contents of aromatics and PAHs at 95% confidence, indicated a significant difference in the diesel fuel quality from the two sources. The study revealed that the diesel fuel quality in use in Nigeria on the bases of PAHs and aromatics content is comparable to the European Union diesel fuel quality specification of a maximum of 4 % m/m PAHs.