Fig. 4 also demonstrates that the sorption capacity of lubricating oil is much higher than that of diesel for three kinds of sorbents. This is mainly attributed to the high viscosity of lubricating oil which could improve the oil sorption capacity by enhancing the adherence of oil onto the sorbent surface, so viscosity of oil is an important indicator for evaluating the oil absorbency of as-prepared material (Abdullah et al., 2010 and Zhu et al., 2011). In addition, the oil viscosity also plays an important role in retaining oil and preventing the absorbed oil from easily escaping from the pores of oil-loaded samples. These results are in accordance with the results of kapok fiber published recently (Rengasamy, Das, & Karan, 2011).