Author(s) :

Pichanath Sirilert.

Volume/Issue :

Abstract :

Laminated kraft paper (LKP) packaging waste and mixed plastic waste (MPW) are substantial contributors to landfill waste due to their heterogeneity, which limits the economic viability of conventional recycling. Furthermore, insufficient research has comprehensively explored the effects of catalyst loading on the steam gasification of composite waste. This study is the first systematic evaluation of the catalytic steam gasification of LKP packaging waste and its co-gasification with MPW using varied loadings of a NiO/La2O3/Al2O3 catalyst in a downdraft fixed-bed reactor at 800 °C. The effects of catalyst loading (0-2 g, C/F = 0-0.4 wt/wt) and plastic co-feeding (20 wt%) on syngas composition and hydrogen yield were evaluated. Under non-catalytic conditions, LKP gasification produced 1.64 L g⁻¹ of hydrogen with an H₂/CO ratio of approximately 3.3. Catalyst addition significantly enhanced reforming and water–gas shift (WGS) reactions. At C/F = 0.2, hydrogen yield increased to 2.22 L g⁻¹, while at C/F = 0.4 it reached 2.42 L g⁻¹. The H₂/CO ratio increased to ~5.0 under catalytic conditions, indicating improved hydrogen selectivity and CO conversion. Light hydrocarbons (C₂–C₃) decreased substantially under catalytic conditions, demonstrating effective hydrocarbon cracking and reforming activity. However, increasing catalyst loading beyond 1 g did not significantly improve performance, indicating kinetic saturation. Co-gasification with 20 wt% MPW at C/F = 0.4 resulted in the highest hydrogen yield (2.56 L g⁻¹) without significant change in H₂/CO ratio. These findings demonstrate effective catalytic upgrading of laminated composite waste into hydrogen-rich syngas using Ni-based catalysis.