High-yield H2 production from HDPE through integrated pyrolysis and plasma-catalysis reforming process

In order to deal with the ongoing rise in plastic trash and the decline in fossil energy, effective technologies for converting polyethylene to hydrogen, which makes up the majority of plastic waste, are urgently needed. This work aims to explore the function of an emerging integrated pyrolysis and plasma-catalysis reforming system for hydrogen production from high-density polyethylene (HDPE). The results showed that plasma and catalyst had strong synergy for hydrogen production under various reforming temperatures, with a synergy effect of 250.98 % at 500 °C. The yields of total gas and hydrogen gas from the plasma-catalysis reforming of HDPE were 146.50 mmol/g and 102.52 mmol/g, respectively, which were more than three times the sum of the gas yields from the plasma-alone reforming process and the catalysis-alone reforming process. Characterization of used catalysts at 500 °C revealed that catalysts from plasma-catalysis reforming had more severe carbon deposition than those from catalysis reforming, because of the long whisker-like deposited carbon in plasma-catalysis mode that kept the surface Ni species exposed and therefore maintained improved stability and activity.