Green synthesis, structural characterization, and catalytic performance of Nd-Modified Fe3O4 nanoparticles using Terminalia catappa extract

This study explores the green synthesis and catalytic performance of neodymium-modified magnetite (Nd/Fe3O4). These materials are produced using Terminalia catappa (Ketapang) leaf extract as a natural reducing and stabilizing agent. Characterization through FTIR, XRD, BET, SEM-EDX, and VSM analysis confirmed that the phytochemicals from the Ketapang extract facilitated the creation of more uniform particles, enabled effective Nd incorporation, and ensured adequate magnetic responsiveness for easy recovery after reactions. The catalytic evaluation showed that Nd loading improved transesterification efficiency. The 1% Nd/Fe3O4 yielded 86.93% biodiesel, while the 3% Nd/Fe3O4 achieved the highest yield of 92.46%, outperforming the conventional NaOH catalyst, which yielded 86.51%. GC-MS analysis of the resulting biodiesel revealed a clear dominance of major FAME compounds, especially methyl palmitate and methyl oleate. This indicates high conversion rates and excellent product purity. Overall, the results demonstrate that green-synthesized Nd/ Fe3O4, particularly with a 3% Nd loading, exhibits enhanced catalytic activity, apparent FAME selectivity, magnetic recoverability, and strong potential for sustainable and scalable biodiesel production.