Biosorption of Heavy Metals Cu²⁺, Cd²⁺, and Pb²⁺ by Chitosan and Powder from Capiz shell (Placuna placenta)

The heavy metal pollution leads to ecosystem disruption and causes a worrying effect on health. On the other hand, Chitosan is an abundant biopolymer which is formed from alkaline N-deacetylation process of chitin and has adsorption ability to remove heavy metal ions. This research aims to evaluate the potential of capiz shellfish, both as chitosan isolate and as raw powder, to become a heavy metal biosorbent. This research examined the potentiality of chitosan and Placuna placenta (Kerang Simping), or Capiz shells waste as biosorbent for three heavy metals, which were Cu²⁺, Cd²⁺, and Pb²⁺. Chitosan was isolated from the Placuna placenta shells through deproteinization, demineralization, and deacetylation processes. The potential as a biosorbent was examined on a column with an inner diameter of 17.5mm and a height of 150mm. Chitosan powder and Capiz shells were packed into the column, then a test solution of 10mg/L was passed into the column with a contact time of 30 minutes. To evaluate the repeated adsorption ability, elution was carried out 2 times. The result showed that there was no significant difference of biosorbent ability between chitosan and Placuna placenta shells powder. Both chitosan and Placuna placenta shells powder were able to remove more than 90% of heavy metal, also at the second elution. The statistical analysis revealed that there was no significant difference between the first and second adsorption.