Abstract

The use of rice and melon husks in their raw, carbonized (at 400°C and 600°C) and activated (using 10%, v/v orthophosphoric acid) form to catalyze the degradation of anthracene in sandy soil was investigated. Rice husk carbonized at 600°C and activated was found to be a better adsorbent than melon husk under same condition. After five weeks of degradation experiment the anthracene reduced from an initial concentration of 5000 to 1009.7 and 1200.2 µg/g soil for rice and melon husks, respectively, while the control reduced to 2671.0 µg/g soil. Result of the batch degradation process of anthracene was found to follow first order heterogeneous kinetics with rice husk carbonized at 600°C and activated having the fastest reaction rate constant of 0.0018 h^-1 followed by melon husk with 0.0016 h^-1 while the control had 0.0009 h^-1.The regression coefficients obtained from the analysis of the experimental data used to test the order of reaction were greater than 88% showing a good reliability of the data obtained.

Key words: Degradation, polycyclic aromatic hydrocarbon, anthracene, rice husk, melon husk.