Synthesis and characterization of heterogeneous catalysts (MgO, CaO/Zeolite-Y) via hydrothermal method for biodiesel productionM. Farhan Fery Ilallah, Sumari Sumari and Aman SantosoE3S Web Conf., 695 (2026) 01003DOI: https://doi.org/10.1051/e3sconf/202669501003