Effects of Ethanol: Water Ratio and Reaction Time on Ethyl Levulinate Synthesis from Oil Palm Empty Fruit Bunch (OPEFB)Christopher Widjaja, Heriyanti, Kritsana Namhaed and Misri GozanE3S Web Conf., 503 (2024) 02003DOI: https://doi.org/10.1051/e3sconf/202450302003