Co-Pyrolysis of Sugarcane Bagasse and Polystyrene with Ex-Situ Catalytic Bed of Metal Oxides / HZSM-5 with Focus on Liquid Yield

Abstract

Catalytic co-pyrolysis of sugarcane bagasse (SCB) and polystyrene (PS) was conducted in a fixed bed reactor over HZSM-5, metal oxide (MgO, CaO) and dual catalyst HZSM-5:CaO, HZSM-5:MgO combinations. Effect of microporous HZSM-5, mesoporous MgO and CaO and dual catalyst mass ratio on pyrolytic liquid yields and chemical composition of liquid organic phase (OP) was examined. Though the catalyst addition decreased the yield of liquid OP, general improvement in mono-aromatic hydrocarbon yield with least content of oxygenates was achieved in the catalytic trials compared to non-catalytic experimental runs. Results revealed that in comparison to metal oxides, acidic HZSM-5 showed maximum conversion efficiency of acids, furans and phenols presenting them as hydrocarbon source for aromatic production. Basic MgO when combined with acidic HZSM-5, was found to conduce better catalytic performance yielding improved oil quality compared to HZSM-5:CaO catalyst. Mass ratio of 1:3 HZSM-5:MgO exhibited most eminent synergistic effect with maximum (56.8wt.%) mono-aromatic hydrocarbon (MAH) yield and lowest (20.8wt.%) poly-aromatic hydrocarbon (PAH) content of. Additionally, increased calorific value and density upgradation comparable to standard diesel fuel quality was observed in the presence of dual catalyst layout.