(116e) Selective Production of Gasoline Range Iso-Alkanes from Polyolefin Plastics

Plastics made of polyolefins are widely used in daily life, such as low-density polyethylene, high-density polyethylene, and polypropylene. Despite a small portion of high-density polyethylene is recycled, most of the used polyolefin plastics are not currently recycled. These plastic wastes are great hydrocarbon sources which can be cracked to fuel range chemicals. Our study has shown that these polyolefins can be selectively transformed to gasoline range iso-alkanes (mainly C7, C8 and C9) at a mild temperature of 350 °C and 1 standard atmospheric pressure, with the help of Y zeolites, which are commonly used in fluid catalytic cracking of crude oil. Product analysis from Fourier-transform infrared spectroscopy and gas chromatography-mass spectroscopy have both confirmed the selective production of the iso-alkanes. In addition, the study also showed that the used zeolites can be regenerated by air combustion and reapplied. These iso-alkanes could be directly adopted or further upgraded to supplement the current gasoline production.