Organic Waste of Vegetable and Fruit Waste as Adsorbent of Nickel (Ni²⁺) in Sea Water Pomalaa, Kolaka District, Southeast Sulawesi

¹ SMAS IT Wihdatul Ummah Kolaka, Kolaka, Indonesia 93511
⁴ SMKN 7 Kolaka, Wundulako, Kolaka, Indonesia 93561
⁵ Department of Fisheries Capture, UHO, Kendari, Indonesia, 93111
⁶ Department of Physics Education, USN, Kolaka, Indonesia 93511

Abstract

Indonesia is the second largest nickel producing country in Indonesia. One of them is in Pomalaa District, Southeast Sulawesi which has large nickel (Ni) reserves. Water quality in Pomalaa District is affected by nickel mining activities. The quality of the affected waters can decrease along with the increasing concentration of nickel. This element is considered dangerous and can pollute the surrounding environment. To remove heavy metals from water, several methods can be used, one of which is adsorption. This very well-known adsorption method has unique advantages, its effectiveness depends on the selection of adsorbents and their various features. The selection of adsorbents that are currently developing is by using natural and renewable materials in water treatment because of their environmentally friendly and non-toxic properties. Materials derived from fruits and vegetables that utilize their original parts or waste can be adsorbents. Activated carbon and biochar derived from vegetables and fruits also show excellent potential for removing metal. Vegetable and fruit waste can be used as adsorbents to absorb nickel metal content (Ni²⁺) in Pomalaa seawater. The nickel content in Pomalaa seawater is 0.0267 mg/L and becomes 0.0173 mg/L after the adsorption process using 5 grams of vegetable and fruit waste.