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Performance Evaluation of Azadirachta indica Leaf on Crude Oil Contaminated Soils

Eno O. N., Ukpaka C. P., Ademiluyi F. T.


The intention of this research was to ascertain the effectiveness of sun-dried and room-dried Azadirachta indica leaf at varying quantities, in the remediation of sandy and loamy soils contaminated with 100ml of crude oil. Gas Chromatography-Mass Spectrometry method was used to test for the physicochemical properties of the materials used for the experiment. The unpolluted loamy soil was observed to contain pH of 6.75, electric conductivity of 10.36µS/cm, Total Oxygen content of 2.99%, Total Nitrogen of 0.091%, potassium content of 36.82942%, phosphorus content of 15.36% and Total Bacteria count of 2.15×102cfu/g. Likewise, The unpolluted sandy soil was observed to contain pH of 6.82, electric conductivity of 21.48µS/cm, Total Oxygen content of 1.18%, Total Nitrogen of 0.036%, potassium content of 24.03681% and phosphorus content of 5.18%. The Total Petroleum Hydrocarbon concentration was monitored against the period of exposure on the environment  for the various soils sample treated with 50g, 60g, 70g, 80g, 90g and 100g Azadirachta indica leaf subjected into sun and room dried environment and the results obtained reveals decrease in TPH concentration. Finally, the research demonstrates that Azadirachta indica leaf is a major remediant found useful in environmental cleanup of a polluted site.


Performance, evaluation, Azadirachta indica, leaf, crude oil, contaminated soils

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