Utilisation of Exhausted Coffee Husk as Low-Cost Bio-Sorbent for Adsorption of Pb2+. tlsr [Internet]. 2022 Sep. 30 [cited 2024 Dec. 23];33(3):229–252. Available from: https://ejournal.usm.my/tlsr/article/view/tlsr_vol33-no-3-2022_12