Study of Mangosteen Peel (Garcinia mangostana L.) Waste Capability to Recover Au(III) and Ag(I) in Aqueous Solution

Mellia Harumi (Department of Food Technology, Soegijapranata Catholic University, Jl. Pawiyatan Luhur IV/1 Bendan Dhuwur, Semarang 50234, Indonesia)
Rian Kurniawan (Institute of Chemical Technology, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany)
Agustiwandina Saputri (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281, Indonesia)
Dian Hanna Saraswati (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281, Indonesia)
Meissha Ayu Ardini (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281, Indonesia)
Sri Sudiono (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281, Indonesia)

Indonesian Journal of Chemistry
Vol 21, No 1 (2021)

Electronic waste (e-waste) has been confirmed containing some precious metals such as gold and silver. Mangosteen peel waste as eco-friendly adsorbent has been studied to recover Au(III) and Ag(I) successfully. Recovery was started through adsorbent preparation, consisting of soxhlet extraction and maceration. About 100 mg of adsorbent was dispersed into Au(III) and Ag(I) solutions in various pH conditions (2–6). The result proves that the optimum adsorptions of Au(III) and Ag(I) are at pH 2 and pH 6, respectively. Au(III) adsorption follows the isotherm model of Langmuir with a maximum capacity of 0.580 mmol/g (114.27 mg/g). Ag(I) adsorption follows the isotherm model of Freundlich with a maximum capacity of 0.511 mmol/g (55.10 mg/g).