Plasma-driven catalytic process for plastic waste upcycling over perovskite-type pre-catalysts

Abstract

The increasing demand for plastics poses significant challenges for post-consumer waste management. In this work, we propose a novel plasma-thermal catalytic tandem process over perovskite-type La_0.6Ca_0.4Co_1–xFe_xO_3−δ (LCCF) pre-catalysts for upcycling plastic waste into H₂ and value-added metal oxide–carbon composite materials. Among the evaluated pre-catalysts, La_0.6Ca_0.4Co_0.2Fe_0.8O_3−δ prepared by ultrasonic spray synthesis (USS) demonstrated the highest performance, achieving an H₂ yield of 54.7 mmol/g_plastic (∼76.6 % of theoretical H₂ production) with a selectivity of 78 %. Morphological differences between pre-catalysts synthesized via USS and co-precipitation appear to play a crucial role in their catalytic efficiency. Life cycle assessment results indicate that the ultrasonic spray synthesis method is more environmentally sustainable than the co-precipitation method for LCCF production. Considering the high H₂ yield during plastic upcycling using the La_0.6Ca_0.4Co_0.2Fe_0.8O_3−δ pre-catalyst prepared by USS, along with its lower environmental impact during pre-catalyst production compared to the co-precipitation method, the plasma-thermal catalytic tandem process using this pre-catalyst offers a promising and sustainable approach to plastic waste upcycling.