Comparison of the Adsorption Ability of MgAl-HC, CaAl-HC, and ZaAl-HC Composite Materials Based on Duku Peel Hydrochar in Adsorption of Direct Green Anionic Dyes oleh Novie Juleanti, Normah Normah, Patimah Mega Syah Bahar Nur Siregar, Alfan Wijaya, Neza Rahayu Palapa, Tamizi Taher, Nurlisa Hidayati, Risfidian Mohadi, Aldes Lesbani