Study on the impact of C-CaO dual-based-loaded catalysts on the co-gasification of biomass and plastics in the steam atmosphere

Abstract

In this study, salix psammophila (SL) and plastic mulch film (PMF) used in farmland were employed as experimental feedstocks. Coconut shell char (HCSC) was utilized as the carbon support for the preparation of HCSC-CaO dual-based-loaded catalysts. Co-gasification experiments were carried out under a steam atmosphere to evaluate the performance of these catalysts. Various experimental parameters, including different Ni/Fe loading ratios, SL and PMF blending ratios, reaction temperatures, and steam flow rates (H₂O/C), were investigated to assess the performance of catalyst in terms of H₂ yield and CO₂ adsorption. Under optimal conditions (feedstock ratio (SL:PMF = 3:1), gasification temperature of 800 °C, and H₂O/C = 4), the Ni-Fe/HCSC-CaO (Ni:Fe = 1:1) catalyst exhibited a high H₂ yield (793.4 mL/g) and a low CO₂ yield (102.0 mL/g). Additional metals (Co, Ce, and Al) were introduced for modification to further enhance the catalytic activity. Among them, the Al-Ni-Fe/HCSC-CaO catalyst (Ni:Fe = 1:1) demonstrated superior catalytic activity, yielding 882.8 mL/g of H₂ and 107.2 mL/g of CO₂. Cyclic experimental tests confirmed the catalyst's excellent thermal stability and high H₂ selectivity. This research presents a novel strategy for the efficient co-gasification of biomass and plastic to produce hydrogen-rich syngas.