Efrillia, F. S., & Fajar, M. (2025). Preparation of Activated Carbon From Kluwek (Pangium Edule) Shells as An Adsorbent for Effective Removal of Free Fatty Acid (FFA) from used cooking oil. Greensusmater, 2(1), 12–16. https://doi.org/10.62755/greensusmater.2025.2.1.12-16