Ga-modified zeolites to convert mixed waste plastics to benzene, toluene, ethylbenzene, and xylene (BTEX)-enriched oil through a dielectric barrier discharge plasma-modified reactor

Abstract

Non-thermal plasma (NTP)-assisted catalytic pyrolysis is a promising technology for producing benzene, toluene, ethylbenzene, and xylene (BTEX) from mixed waste plastics. A primary challenge in this approach is the need to achieve a high selectivity for the target products. To address this challenge, this study focused on the preparation of Ga-modified zeolites. The results showed that Ga loading was effective in increasing BTEX yields for the zeolites of USY, β, and HZSM-5 by 7.49%, 4.72%, and 8.63%, respectively. Among these zeolites, HZSM-5-Ga-N2 was the most suitable for catalyzing the NTP-assisted pyrolysis reaction to produce BTEX hydrocarbons, with a maximum selectivity of 63.19% and a maximum yield of 31.84%. This was because the pore of HZSM-5 matched the ring size of BTEX, and NTP improved the distribution of Ga2O3 active sites, allowing more acidic active sites to participate in the catalytic reaction. This work provides an applicable solution to increase the selectivity and yield of BTEX from NTP-assisted pyrolysis of mixed waste plastics with Ga-loading catalysts.