Adsorption of Cu(II) Metal Ions Using Matoa (<i>Pometia Pinnata</i>) Shell Immobilized with Silica Gel

The Industrial Revolution, along with the rapid increase in population, has significantly contributed to the intensification of environmental challenges, mostly the contamination of aquatic ecosystems by heavy metals. One metal that is dangerous for the environment and human health is copper (Cu). The threshold for Cu(II) allowed in water is 0.2 mg L–1. One method to overcome this metal ion pollution is by biosorption using biological material adsorbents. Matoa shell, utilized as a biosorbent, has demonstrated its ability to effectively bind heavy metal ions through its functional groups, which facilitate the formation of complexes with these ions. Biosorbent immobilized using silica can provide increased functional group reactivity and bond resistance. This research uses a batch method by studying several variations of adsorption optimization parameters. The results of each variation of the adsorption parameters showed that the optimum state of adsorption of Cu(II) metal ions was obtained at pH 6 and a concentration of 200 mg L–1 with an adsorption capacity of 13.13 mg g–1. The research results show that immobilizing matoa shell with silica gel can be a low-cost and effective adsorbent in removing Cu(II) metal ions.