Synthesis and catalytic applications of analcime zeolites derived from coal fly ash waste

This study presents the hydrothermal synthesis of analcime zeolite using coal fly ash (CFA), an industrial waste, as a cost-effective and sustainable raw material. The synthesized materials were characterized using XRD, SEM, TGA, N₂ adsorption desorption isotherms, NH₃-TPD, and FT-IR spectroscopy. The catalytic efficiency of the zeolites was evaluated in the esterification of levulinic acid with n-butanol to produce n-butyl levulinate, a valuable compound used in solvents, plasticizers, and biofuel additives. The optimized catalyst, FANA^H-10Al, exhibited exceptional performance, achieving a 97.6 % conversion of levulinic acid and a 94.1 % yield of n-butyl levulinate under moderate conditions (12.5 wt% catalyst loading, 117 °C, 4 h, 1:7 LA to n-butyl alcohol mole ratio). These results highlight CFA-derived zeolites' high catalytic activity and efficiency, demonstrating their potential as sustainable catalysts for biomass-derived chemical synthesis. This work addresses the gap in utilizing CFA-based zeolites in catalysis and establishes their viability for industrial applications.