Production of Plastic-Derived Fuel by Cohydrocracking of Different Polyethylene Terephthalate (PET) with Vacuum Gas Oil (VGO)

Abstract

To promote the chemical recycling of polyethylene terephthalate (PET), its valorization by hydrocracking was investigated. To ease the implementation at large-scale of this valorization route, the PET was coprocessed with vacuum gasoil (VGO), which is a benchmark feed of the industrial hydrocracking unit (10 and 90 wt %, respectively) and hydrocracked using a PtPd/HY catalyst. Furthermore, the suitability of using PETs of different natures and origins to produce fuel-assimilable streams was assessed. Specifically, one virgin, one commercial, and one mechanically recycled PETs were used, analyzing the differences in the conversion, yields of product fractions (dry gas, liquefied petroleum gases, naphtha, and light cycle oil), and composition of naphtha and light cycle oil fractions, given their possible interest of being used in the formulation of automotive fuels. The reaction runs were performed in a batch reactor under the following conditions: 80 bar, 420 °C, 120 min, and a catalyst/feed mass ratio of 10 g_catalyst g_feed^–1. The modified and degraded plastics were more easily converted into liquid hydrocarbons within the naphtha and LCO fractions with contents of isoparaffins between 45 and 50 wt %. From the composition of the liquid products, the possible hydrocracking pathways of the PET-derived molecules were evaluated.