Hydrogen-Rich Gas Production from Municipal Solid Waste via Integrated Pyrolysis and Catalytic Steam Reforming over Ni/Al2O3 Catalyst

Abstract

The transition to a hydrogen-based economy requires efficient and sustainable tech-nologies to convert waste into clean energy carriers. This study investigates the pro-duction of hydrogen-rich gas through the integrated pyrolysis steam reforming (PSR) and integrated pyrolysis (PYR) and catalytic steam reforming (PCSR) of real Municipal Solid Waste (MSW). PCSR experiments were conducted in a two-stage series reactor system: an initial pyrolysis stage at 500 °C followed by a catalytic steam reforming stage at 900 °C over a commercial Ni/Al₂O₃ catalyst (9.8 wt.% Ni). Three real MSW samples from the Serra Gaúcha region (Brazil) were evaluated: organic-rich (A), pol-ymeric-rich (B), and a mixed real-collection fraction (C). Gas yields from PYR to PCSR jumped from 0.44 to 1.18 Nm³·kgMSW⁻¹ and from 0.66 to 1.54 Nm³·kgMSW⁻¹ and from 0.35 to 1.50 Nm³·kgMSW⁻¹ for (A), (B) and (C) samples, respectively. Hydrogen con-centrations of PCSR were between 32-39%vol for all samples, with a marked reduction in CH₄ and CO levels due to the promotion of water-gas shift and methane reforming reactions over the nickel active sites. The PCSR process using a Ni/Al₂O₃ catalyst proves to be a highly effective route for maximizing hydrogen production from real MSW, offering a robust technological solution for energy valorization and carbon footprint reduction.