(724f) One-Dimensional Model of a Two-Stage Molten-Metal Bubble Column Reactor for H2 Production from Polypropylene Pyrolysis

A one-dimensional (1D) reaction model is presented for a two-stage molten metal bubble column reactor (2-stage MMBCR) used for hydrogen production from polypropylene (PP) pyrolysis. In the first stage reactor, solid PP decomposes into hydrogen and gas-phase hydrocarbons (C1-C4), which was modeled by an empirical equation. The second stage reactor for hydrocarbon pyrolysis in the MMBCR was represented by a one-dimensional plug flow reactor (PFR) model with non-catalytic and catalytic reactions. Catalytic reactions occurred at the gas-liquid interfacial area, while non-catalytic reactions took place within the bubble volume. The 2-stage MMBCR model was validated against experimental data over a wide range of operating temperatures. The H₂ yield was compared for 2-stage MMBCRs with Sn and Ga-Sn alloys. This study provides insights for designing the reactor size and optimizing the operating conditions of 2-stage MMBCRs to produce H₂ from waste plastics.