Radioassay of prominent Nigerian fossil fuels using gamma and TXRF spectroscopy

Mokobia, C.E.; Adebiyi, F. M.; Akpan, I. O.; Olise, Felix S.; Tchokossa, P.

doi:10.1016/j.fuel.2006.03.002

Cited by 25 publications

(18 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The report of Mokobia et al (2006) on the radioassay of some Nigerian fossil fuels (coal and bitumen) showed a strong correlation between the levels of metals and radionuclides in the fossil fuels. The higher the concentrations of metals was, the higher the specific activity concentrations of radionuclides in the fossil fuels (Figs.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Natural radioactivity and trace metals in crude oils: implication for health

Ajayi

Torto

Tchokossa

et al. 2008

Environ Geochem Health

View full text Add to dashboard Cite

Crude oil samples were collected from six different fields in the central Niger Delta in order to determine their natural radioactivity and trace element contents, with the aim of assessing the radiological health implications and environmental health hazard of the metals, and also to provide natural radioactivity baseline data that could be used for more comprehensive future study in this respect. The activity concentrations of the radionuclides were measured using a well, accurately calibrated and shielded vertical cryostat, Canberra coaxial high-purity germanium (HPGe) detector system, and the derived doses were evaluated. The metal concentrations were determined by the graphite furnace atomic absorption spectroscopic (GFAAS) method. The radionuclides identified with reliable regularity belong to the decay series of naturally occurring radionuclides headed by (238)U and (232)Th along with the non-decay series radionuclide, (40)K. The averaged activity concentrations obtained were 10.52 +/- 0.03 Bq kg(-1), 0.80 +/- 0.37 Bq kg(-1) and 0.17 +/- 0.09 Bq kg(-1) for (40)K, (238)U and (232)Th, respectively. The equivalent doses were very low, ranging from 0.0028 to 0.012 mSv year(-1) with a mean value of 0.0070 mSv year(-1). The results obtained were low, and hence, the radioactivity content from the crude oils in the Niger delta oil province of Nigeria do not constitute any health hazard to occupationally exposed workers, the public and the end user. The concentrations of the elements (As, Cd, Co, Fe, Mn, Ni, Se and V) determined ranged from 0.73 to 202.90 ppb with an average of 74.35 ppb for the oil samples analysed. The pattern of occurrence of each element agreed with the earlier studies from other parts of the Niger Delta. It was obvious from this study and previous ones that the Niger Delta oils have low metal contents. However, despite the low concentrations, they could still pose an intrinsic health hazard considering their cumulative effects in the environment. Also, various studies on the impact of oil spillage and activities of oil exploration and production on organisms in the immediate environment suggest this.

show abstract

Section: Resultsmentioning

confidence: 99%

“…In addition, radon gas, a radium daughter, may be found in produced natural gas. In gas processing activities, NORM generally occurs as radon gas in the natural gas stream (Mokobia et al 2006).…”

Section: Introductionmentioning

confidence: 99%

Natural radioactivity and trace metals in crude oils: implication for health

Ajayi

Torto

Tchokossa

et al. 2008

Environ Geochem Health

View full text Add to dashboard Cite

show abstract

“…The concentrations recorded for the following elements: Al, Ti, V, Na, K, Mn, La, Sm, Sc, Cr, Fe, Rb, Lu, Ni, Hf, Ce and Th in the unextracted sample were comparatively higher than their respective concentrations in asphaltene and maltene portions of the sample. However, some elements such as Ca, Dy, Zn, Sb, Ba, Eu, Ta, Mg, and Cl were found to fall below their detection limits 10 . However, the concentration of Ni (59.4 µg/g) in the unextracted sample was comparable with the value reported by Mokobia et al, 10 The asphaltene portion of the sample showed tremendous reduction in the concentrations of its constituting elements ( unextracted sample.…”

Section: Sample Irradiation and Radioactivity Measurementmentioning

confidence: 97%

“…However, some elements such as Ca, Dy, Zn, Sb, Ba, Eu, Ta, Mg, and Cl were found to fall below their detection limits 10 . However, the concentration of Ni (59.4 µg/g) in the unextracted sample was comparable with the value reported by Mokobia et al, 10 The asphaltene portion of the sample showed tremendous reduction in the concentrations of its constituting elements ( unextracted sample. Conversely, the concentrations of the elemental constituents of the maltene portion of the sample were relatively lower than those recorded in its asphaltene counterpart.…”

Section: Sample Irradiation and Radioactivity Measurementmentioning

confidence: 97%

Neutron Activation Analysis of Some Nigerian Bitumen Samples and their Components

Ogunsuyi¹,

Ajayi²,

Ipinmoroti³

et al. 2012

Orientjchem.

View full text Add to dashboard Cite

Bitumen is a mixture of organic liquids that are viscous, black, sticky and soluble in most organic solvents. The composition of bitumen has been variously reported to consist of highly condensed polycyclic aromatic hydrocarbons (PAH), heterocyclic compounds and heavy metals such as nickel, vanadium, lead, chromium, mercury, arsenic, selenium, manganese and other toxic elements 1 ABSTRACTPreliminary examination of the elemental contents of bitumen samples from three deposits in Odigbo Local Government Area of Ondo State, Nigeria and their respective major components (maltene and asphaltene) was undertaken using neutron activation analysis technique. Samples were obtained from tar sand outcrop, near-surface and borehole deposits in Ilubirin and Agbabu mines of the Afowo Formation in the Benin Basin of Southwestern Nigeria. 30 Elements were detected in measurable quantities in these samples with variation in the elemental distribution reflecting the chemical composition of the source. Notable among the elements were Al, Na, K, V, La, Sm, Ni and Pa to mention a few. For instance, 21 elements were detected at measureable concentration in the borehole sample compared with 18 from the tar sand and 20 from near surface bitumen sample. It is noteworthy that the highest concentration level of most elements was encountered in the tar sand sample compared with the other two sources. Maximum concentrations of Al (2624 µg/g), Ti (856.4 µg/g) and V (142.6 µg/g) were recorded for the tar sand sample. Generally, the concentrations of these elements in the samples were significantly different from each other (P≤0.05). The result showed strong positive correlation among the 3 bitumen samples indicating that they are geologically and genetically related. The findings were also complemented with the x-ray diffraction of the sand residue; which was largely characterized by silica (SiO 2 ).

show abstract

“…Besides, there are a number of industrial activities which may concentrate radionuclides particularly members of the 232 Th and 238 U decay series, in products and by-products or wastes (Abbady and El-Arabi, 2006;IAEA, 2006). A characteristic of NORM is that because of their wide distribution, they give rise to a very much larger radiological effect to the public compared with that caused by, for instance the nuclear industry (Mokobia et al, 2006). Also as technology develops so the waste streams from established industries may be causing new problems as they may be concentrating NORM in their waste to levels that are now exceeding the point at which regulatory concerns is required for radiation protection purposes (IAEA, 2006).…”

Section: Introductionmentioning

confidence: 99%

Radionuclide contents and physico-chemical characterization of solid waste and effluent samples of some selected industries in the city of Lagos, Nigeria

Jibiri

Adewuyi

2008

Radioprotection

View full text Add to dashboard Cite

The radionuclide contents in waste products and physico-chemical characterization of effluent samples from some selected industries in the city of Lagos were carried out. The radioactivity concentration levels due to 40 228 Th it ranged between 14 ± 2 Bq kg -1 and 73 ± 10 Bq kg -1 . No artificial radioactive elements were detected in any of the samples. The average outdoor effective dose rate due to gamma exposure from these waste materials in the city was calculated as 0.12 mSv y -1 . This is far less than 1 mSv y -1 recommended limit for the member of the public by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The pH of the effluent samples was slightly alkaline, while the electrical conductivity ranged between 275 and 455 µS cm -1 and total suspended solids ranged from 104 to 5616 mg l -1 . All these ranges and those of biochemical and chemical oxygen demand values were all higher than the prescribed limits. Presence of heavy metals in the effluent samples was however lower than prescribed with the exception of iron. Keywords

show abstract

Radioassay of prominent Nigerian fossil fuels using gamma and TXRF spectroscopy

Cited by 25 publications

References 3 publications

Natural radioactivity and trace metals in crude oils: implication for health

Natural radioactivity and trace metals in crude oils: implication for health

Neutron Activation Analysis of Some Nigerian Bitumen Samples and their Components

Radionuclide contents and physico-chemical characterization of solid waste and effluent samples of some selected industries in the city of Lagos, Nigeria

Contact Info

Product

Resources

About