3. Results and Discussion
3.1. Preparation of distillation fractions
The raw material was distilled in the packed column and four distillation fractions were obtained according to normal boiling points. They are: Fraction I (30–90 °C) that mainly contains C1–C3 alcohols and C5–C7 alkanes, Fraction II (90–140 °C) that mainly contains C4–C5 alcohols and n-octane, Fraction III (140–190 °C) that mainly includes C6–C8 alcohols and C10–C12 alkanes, and Fraction IV (> 190 °C) that mainly includes C10–C18 alcohols and C12–C21 alkanes. The composition of each fraction is shown in Table 2. The polarities of the primary alcohols in each fraction are similar and the 50–60 °C boiling range of the fractions is convenient for choosing the utilities in designing distillation system.