Pengaruh Waktu Kontak terhadap Kemampuan Adsorpsi Ion Pb2+ oleh Bioadsorben Kulit Kopi Robusta Teraktivasi Asam Fosfat (H3PO4)

Abstract

Heavy metal pollution, particularly lead contamination in wastewater, has become a serious issue in recent years due to their resistance to degradation and high toxicity. A bioadsorben made from Robusta coffee husk activated with 2M phosphoric acid was used to adsorb Pb2+ ions present in wastewater. This study was conducted to analyze the effect of contact time on the adsorption of Pb2+ ions by the biaoadsorbent. The concentration of Pb2+ ions was analyzed using Atomic Absorpstion Spectrophotometry (AAS). The Result showed that the adsorption capacity increased with increasing contact time until reaching an optimum condition, after which it began to decline. Optimal adsorption eficiency was achieved at a contact time of 60 minutes at 97,03%, with 97,0322 ppm of Pb2+ ions succesfully adsorbed from an initial concentration of 100 ppm. Based on the result obtained, Robusta coffee husk bioadsorbent has the potential to serve as an environmetally friendly adsorbent and can be used in the treatment of heavy metal wastewater, particularly lead in water bodies