Novel Electrified Thermal Hydrogen Production Approaches

In this study, we investigated four advanced electrification-based hydrogen (H2) production approaches, including direct Joule heating-assisted steam methane (CH4) reforming (DJH-SMR), microwave (MW) heating-assisted chemical looping dry reforming of CH4 (MWH-CLDRM), microwave heating-assisted CH4 thermal pyrolysis (MWH-MTP), and microwave heating-assisted low-density polyethylene (MWH-LDPE) pyrolysis. In the DJH-SMR, we employed an electrically conductive catalyst in a fluidized bed and achieved 96% CH4 conversion with H2/CO ratio of over 3 (CO is the carbon monoxide) at bulk temperature Tb of 900°C and steam-to-carbon molar ratio of 1. In the MWH-CLDRM, we leveraged MW irradiations to selectively heat magnetite (Fe3O4), achieved 97% CH4 conversion at Tb of 800°C in the fuel (reducer) reactor with an H2/CO ratio of 2, while suppressed coke formation. With the MWH-MTP, we demonstrated 23% CH4 conversion at Tb of 1065°C with 98% H2 selectivity, while capturing 90% of produced solid carbon. The MWH-LDPE pyrolysis over an iron-nickel-alumina catalyst at Tb yielded 72% H2 and 52% of carbon nanotubes. Obtained results highlighted the DJH-SMR's potential for H2-rich streams, MWH