<p>This study investigates hydrogen-enriched syngas production through a bi-level fixed-bed pyrolysis-catalytic steam reforming (PCSR) process using both individual lignocellulosic biomass components and actual waste biomass. Sawdust-derived biochar was employed as a catalytic medium in the reforming zone. Thermogravimetric analysis (TGA) was conducted to assess the thermal decomposition behavior of cellulose, hemicellulose, lignin (CHNL), and the waste biomass. Among the components, lignin exhibited the highest H₂ and syngas yields during reforming over biochar, indicating its superior reformability. When CHNL components were co-processed, the combined system displayed a clear synergistic effect, yielding 21.5% more H₂ compared to the theoretical additive value, thus demonstrating non-linear enhancement from component interactions. To elucidate the catalytic contribution of alkali and alkaline earth metals (AAEMs), potassium and calcium salts were introduced into the CHNL mixture. Their addition significantly boosted H₂ and CO yields, confirming their role in promoting reforming reactions. Experiments with real waste biomass revealed gas yields that differed markedly from the predicted additive behavior of CHNL constituents, highlighting the complex interplay of chemical interactions in actual feedstocks. Moreover, biochar not only acted as a catalytic substrate but also underwent <b>self-gasification</b>, contributing additional gas-phase reactants and amplifying overall H₂ production. This dual functionality underscores biochar’s role as both a catalyst and reactive agent in the reforming environment. Overall, the results demonstrate that integrating co-pyrolysis with catalytically active biochar and AAEMs in a bi-level reactor framework can significantly enhance hydrogen yield. This strategy presents a viable and sustainable route for efficient H₂ production from lignocellulosic waste biomass.</p> Graphical Abstract <p></p>