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Terpane Characterization of Crude Oils from Niger Delta, Nigeria: A Geochemical Appraisal
Mark Obinna Onyema,
Michael Junior Ajie
Issue:
Volume 7, Issue 1, June 2023
Pages:
1-6
Received:
29 November 2022
Accepted:
26 December 2022
Published:
20 March 2023
Abstract: The geochemistry of crude oils from the Niger Delta, Nigeria, were evaluated using the characterization of C19 to C35 terpanes. Analyses of two representative crude oils from Western and Central Niger Delta showed abundances of C19 to C29 tricyclic terpanes constituted 12.09% and 29.74%, C24 tetracyclic terpane 0.31% and 0.15% and C27 to C35 pentacyclic terpanes 87.61% and 70.12%, respectively. Diagnostic ratios of terpanes indicated relatively low abundances of C23, C28 and C29 tricyclic terpanes, low abundances of homohopanes, a significantly high abundance of oleanane and that the Niger Delta crude oils were derived from terrestrial organic matter source rocks deposited in an oxic environment during the Tertiary period. Multivariate oil-oil correlation plot showed the Western and Central Niger Delta crude oils are not distinct, but moderately related (genetically). However, diagnostic ratios of C24 tetracyclic terpane, which was high and moderate and gammacerane, which was low and high, revealed crude oils from Western Niger Delta were derived from predominantly terrestrial source and crude oils from Central Niger Delta were derived from terrestrial source with input from marine organic matter, respectively. Tricyclic terpanes/hopanes and isomerization ratios of C32 homohopanes indicated the Niger Delta crude oils were generated at high maturity, at top of the oil generation window.
Abstract: The geochemistry of crude oils from the Niger Delta, Nigeria, were evaluated using the characterization of C19 to C35 terpanes. Analyses of two representative crude oils from Western and Central Niger Delta showed abundances of C19 to C29 tricyclic terpanes constituted 12.09% and 29.74%, C24 tetracyclic terpane 0.31% and 0.15% and C27 to C35 pentac...
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Optimization of the Oxidative Desulphurization of Residual Oil Using Hydrogen Peroxide
Sadiq Tijjani Ahmed,
Chika Muhammad,
Aminu Bayawa Muhammad,
Ibrahim Muhammad Danmallam,
Sirajo Abubakar Zauro,
Bilyaminu Ahmad Rafi
Issue:
Volume 7, Issue 1, June 2023
Pages:
7-13
Received:
4 February 2023
Accepted:
24 February 2023
Published:
11 April 2023
Abstract: The role of fuel in global economy cannot be overemphasized, it is necessary to develop new and more efficient technologies in desulphurization processes at a low cost. This research focuses on optimization of desulphurization using oxidative method for higher yields, utilizing dual acetic/formic acid catalyst on residual oil with sulphur concentration > 0.50%wt and emphasizes the improvement of physicochemical properties primarily suitable for use in fuels where regulation is becoming more stringent. The process was conducted using H2O2 oxidant concentration 12.5-25.0% (w/w), CH3COOH/HCOOH acid catalyst mixture 12.5-22.0% (w/w), and reaction temperature 40-60°C. Optimization of the desulphurization parameters was done using response surface methodology based on Box-Behnken design. The optimum yield of desulphurization (60.93%) was achieved at the oxidant 18.75% (w/w), acetic/formic mixture of 17.25% (w/w), and reaction temperature of 50°C. In general, the experimentally confirmatory figures in two solutions of 63.29 ± 0.47% and 61.04 ± 0.13% match the predicted values of 62.82% and 60.91%, respectively. The total sulphur content in residual oil was reduced from 0.67 to 0.26%wt. GC-MS of the untreated sample confirm the presence of 1,2-benzisothiazole,3-(hexahydro-1H-azepin-1-yl)-1,1-dioxide, Nickel(II)bis(N,N-dihexyldithiocarbamate and Diethyl[3-[n-octadecylmercapto]-P-n-butyl-anilino methy lene] malonate with a total percentage peak area of 11.83%. In the treated sample shows no sulphur compounds. The physicochemical analysis for both treated and untreated residual oil according to ASTM were found to be within acceptable limit except sulphur content of untreated sample. After the desulphurization, treated residual oil shows a remarkable improvement in the physicochemical parameters. Hence can be applicable in industrial process and automobiles with very low sulphur emission.
Abstract: The role of fuel in global economy cannot be overemphasized, it is necessary to develop new and more efficient technologies in desulphurization processes at a low cost. This research focuses on optimization of desulphurization using oxidative method for higher yields, utilizing dual acetic/formic acid catalyst on residual oil with sulphur concentra...
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Predictive Analytical Model for Hydrate Growth Initiation Point in Multiphase Pipeline System
Akinsete Oluwatoyin,
Obode Elizabeth,
Isehunwa Sunday
Issue:
Volume 7, Issue 1, June 2023
Pages:
14-21
Received:
17 January 2023
Accepted:
14 February 2023
Published:
15 April 2023
Abstract: Gas hydrates account for a huge flow assurance encounter in the passage of natural gas through pipelines. Its undesirability stems from the fact that these solids reduce pipe diameter open to gas flow, and challenge pipeline integrity, therefore leading to bursting pipes and increasing costs. Hydrates undergo four phases of development: entrainment, growth, agglomeration and plugging – and do not usually constitute a flow assurance challenge until agglomeration. These challenges are even more pronounced in the presence of condensate in the pipeline. This study was therefore designed by developing a predictive model of the hydrate growth initiation point along the pipeline where hydrates start to form in the presence of gas, condensate, and water. The developed predictive analytical model at which quasi liquid layer starts to form on the hydrate seed relates the quasi-liquid layer temperature to the gas hydrate mass, pipeline length, induction time, hydrate percentage in the fluid composition, hydrate density, change in enthalpy and the flowing hydrate velocity in the pipe system. The developed predictive model will assist in identifying when heating of pipelines can be done to control hydrate formation by keeping the temperature above the quasi-liquid layer temperature. This predictive model was in concordance with field observation.
Abstract: Gas hydrates account for a huge flow assurance encounter in the passage of natural gas through pipelines. Its undesirability stems from the fact that these solids reduce pipe diameter open to gas flow, and challenge pipeline integrity, therefore leading to bursting pipes and increasing costs. Hydrates undergo four phases of development: entrainment...
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