Materials and Methods
Two kinds of vegetable oil derived from the fleshy fruits and seeds ofElaeis guineensis (PO and PKO, respectively) were donated by local farmers in Abatete, Anambra State, while SBO was purchased from Ose Market, Anambra State, Nigeria.
The vegetable oil samples were first analyzed for their physicochemical properties and then part of each was modified by reacting them with excess 1-heptanethiol in the presence of ultraviolet light (UV at a wavelength of 300 nm) such that they become thioether functionalized (TF) [12]. In a typical modification experiment, 100 g of oil was reacted with 30 g, 20 g or 65 g of heptanethiol to obtain crude TF-PO, TF-PKO, or TF-SBO, respectively. Thereafter, the modified oil (TF-VO) samples were respectively recovered from the crude mixture (with excess/unreated heptanethiol) by simple distillation. The sulphur-modification reaction is as given in Figure 1.