However, the heavy oil fraction was still high in the oil from HDPE waste as shown in Fig. 4(b) indicating the
low quality of the oil. The liquid products have been classified into three groups i.e. the gasoline fraction (C5-C12),
diesel fuel fraction (C13-C20) and heavy oil (>C20). As can be seen in Fig. 4(b), PE bag 2 produced highest diesel
fraction while PE bag 1 produced highest gasoline fraction. As mentioned previously, the organic materials presence
in PE bag 1 contributed to the high fraction of gasoline as reported by Lei et al. [21] for biofuel production. It was
found that C6-C14 chemical compounds were up to 95% of bio-oils. HDPE waste yielded lower diesel fuel fraction
than that of PE bag 2. This is due to the different materials in PE bag 2 which consist mostly of low density
polyethylene.