Data from Yogyakarta’s Environmental Agency in 2017 revealed that heavy metal contents of lead and manganese in Code River are very high, reaching 0.14 mg/L and 0.15 mg/L. The number is quite alarming because it exceeds the predefined quality standard of 0.03 mg/L and 0.1 mg/L.
The issue prompted three UGM students to study adsorbent materials that can reduce heavy metal concentrations in Code River water. From their research funded by Higher Learning Directorate General through the Student Creativity Program, they discovered the potential of Ambon banana peel waste as an effective adsorbent. The research used three types of banana peel waste to be compared, including Ambon, Saba, and Musa Belle. The characterization test result showed that Ambon banana peel waste with H3PO4 concentration of 2.0 M is closest to the criteria to serve as adsorbent
The sampling point determination was carried out using the slope-area method, by measuring the discharge of Code River as the base. From the research, they found that Ambon banana peel waste was most effective because its characteristic fulfilled the quality standard of Indonesian activated carbon, namely moisture content by 6.67%, ash content by 4.90%, and adsorbability by 5397.39 mg/g. Moreover, the activated carbon of Ambon banana peel with 2 M activator concentration succeeded in reducing Pb and Mn level as identified in Code River consecutively by 41.67% and 65.72%.
