(2026) Journal of Environmental Chemical Engineering_Integrated valorization of pineapple peel by coupling levulinic acid production with CO₂-mediated pyrolysis

Park J.; Cho S.-H.; Lee Y.-J.; Park S.-J.; Kwon E.E.

(Elsevier Ltd) Journal of Environmental Chemical Engineering ISSN: 22132929 Vol.14 Issue.2 Article No.121831 DOI: 10.1016/j.jece.2026.121831

Levulinic acid (LA) is a platform chemical derived from C₆ mono-/poly-saccharides in lignocellulosic biomass, serving as a versatile precursor for the synthesis of various chemicals. However, its production unavoidably remains lignin-rich residues during the recovery of C₆ carbohydrates, which undermines the environmental sustainability of LA production. To address this challenge, this study proposed an innovative strategy that converts hydrolysis residue into both syngas and CO₂ sorbent to enhance the sustainability of LA production. Pineapple peel (PP) was employed as the feedstock. Acid-catalyzed hydrolysis of PP produced LA with a maximum concentration of 11.19 g L⁻¹ under 2 M H₂SO₄. The resulting PP residue was subsequently subjected to CO₂ mediated pyrolysis. CO₂ acts as both a reaction medium for gas-phase reactions and activation agent for pore development of biochar. To promote these gas-phase reactions, catalytic pyrolysis over Ni/Al₂O₃ was performed, which accelerated CO generation under CO₂ condition (46.38 mmol) compared to N₂ condition (6.74 mmol). To maximize carbon utilization, the biochar generated from CO₂-mediated pyrolysis was evaluated as a CO₂ sorbent. Compared with N₂-derived biochar, the CO₂-derived biochar exhibited more developed meso- and microporous structures. Although both biochars achieved comparable CO₂ adsorption capacities (39.33 mg g⁻¹), the CO₂-derived biochar showed a faster adsorption rate. Overall, this work demonstrates an integrated approach to valorizing hydrolysis residues in LA production, coupling syngas generation with biochar-based CO₂ capture to improve carbon efficiency and process sustainability. © 2026 Elsevier Ltd.

This study was supported by the National Research Foundation of Korea (NRF) grants funded by the Korean government (MSIT) (No. RS-2023-NR077231). This work was also supported by a New Faculty Research Grant of Pusan National University, 2024.