Characterization of Prigi South Coast Coral and Its Development as Adsorbent of Nickel Ions

Departement of Chemistry, Faculty of Mathematic and Natural Science, Universitas Negeri Malang Jl. Semarang 5 Malang 65145, Malang, Indonesia

^* Corresponding author : anugrah.ricky.fmipa@um.ac.id

Abstract

The abundance of dead coral reefs or coral skeleton around the coast of Prigi Beach has the potential to be abundant and used as an adsorbent to reduce nickel content. Nickel in high concentrations can cause water pollution problems. It is urgently needed for the development of adsorbents at this time. This study aims to determine the characterization of coral adsorbents using XRF, SEM, and FT-IR and to then determine the optimization of the size and contact time of corals in the nickel ion adsorption process. The stages of this research consisted of taking coral samples at Prigi beach, production coral adsorbents using the pyrolysis method, coral activation process, characterization of corals with XRF, FTIR and SEM and application of coral adsorbents for nickel metal ion adsorption. The FT-IR results show the O-H vibration of the carboxylate group at a wave number of 3232.70 cm^-1, aliphatic C-H bending vibration at a wave number of 2916.37 cm^-1. Strain vibrations at wave number 1788.01 cm^-1 are associated with C=O ketones and in the range 1247.94 cm^-1 indicate C-O strain vibrations. SEM analysis found that corals had a rough morphology and the presence of micropores. The adsorption efficiency showed that the adsorbent at 200 mesh size was able to absorb the highest nickel ion of 84.52% with a contact time of 168 hours.