Adsorption experiments were conducted in artificial seawater,
which was prepared artificially as has been previously described by
Kester et al. [26]. Table 2 shows the composition of the artificial sea
water. 20 g of crude oil, vegetable oil and diesel fuel, were poured
into separate 500 ml conical flask with 200 ml of seawater. Varying
amounts of the sorbents (0–8 g) were added with a 60 min contact
time following the ASTM F 726-99 standard method for testing oil
spill sorbents [27]. Oil concentrations were measured based on
US-EPA method 1664 [28]. Oil adsorption capacities (mg/g) were
obtained from the following equation: