pH and Sulphate mass: Intensity factors in investigating sulphatedependent degradation of polycyclic aromatic hydrocarbons

Luke N. Ukiwe* and Ugochukwu U

Abstract

The ability of pH and sulphate masses in influencing the rate of degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil leachate was studied. Results obtained indicated that using 2 g sodium sulphate (Na2SO4) about 14.0 % of 2-methylnaphthalene was degraded as the highest PAH at pH 4.0, while anthracene (1.1 %) was the least degraded PAH. However, using 4 g Na2SO4, 11.5 % of 2-methylnaphthalene was the highest degraded PAH, while fluoranthrene and pyrene were not detected. It was also found that a trend in PAHs degradation was observed as the pH was increased from 2.0, 4.0 and 6.0 using 2 g Na2SO4. Nevertheless, this trend in PAHs degradation was not replicated using 4 g Na2SO4. The two-ring PAHs showed high degradation potential using both Na2SO4 masses. However, it was revealed that increasing the weight of Na2SO4 from 2 to 4 g had no notable effect in PAHs degradation.