Performance of Kulon Progo low grade manganese ore leaching using acetic acid and its selectivity

Abstract

The need of manganese to support human life has led to the exploitation of low-grade manganese ore. However, the appropriate technique has not been established and still under development. Having total amount of 120 thousand metric tons, Indonesia has huge potential of low grade manganese ore deposited in several areas such as Kulon Progo, Yogyakarta. In this study, leaching of low grade manganese ore was conducted using acetic acid which isenvironmentally friendly due to its ease to decompose naturally. Ore characterization was performed by X-Ray Diffraction (XRD), X-Ray fluorescence (XRF), and Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS) showing that 7.16 % is manganese while 32 % of the ore is dominated with calcite. Effects of leaching temperature and particle size on Kulon Progo low grade manganese ore were investigated. Particle sizes under study were less than 200 mesh and between 70 mesh and 100 mesh. The pH and temperature of experiment were varied on 0.7, 1.7, and 3; and 30 °C, 60 °C and 80 °C, subsequently. It was obtained that the ore particle size has no significant effect on Mn recovery. The manganese recovery of 76.08 % was obtained, containing lower recovery of calcium and iron which were 10%. The findings showed acetic acid is more selective towards manganese than to calcium and iron.