Enhancing Titanium Content on Red Mud using Leaching Technique using Bromic Acid

¹ Chemical Engineering Department, Universitas Islam Indonesia, Jalan Kaliurang km 14,5 Yogyakarta 55584, Indonesia
² Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan

^* Corresponding author: arif.hidayat@uii.ac.id

Abstract

Red mud, as the main waste product of the bauxite processing industry, still has potential for utilization through the extraction of valuable metals such as titanium. This study examines the effect of bromide acid concentration, temperature, and leaching time on increasing the titanium content in solid residues. The experimental results show that the optimum conditions are achieved at a HBr concentration of 4.41 mol/L with a titanium content of 3.46 wt.%, while higher concentrations reduce the effectiveness of leaching due to the formation of a secondary phase. A reaction time of six hours produced a maximum content of 3.78 wt.%, while increasing the temperature to 75 °C increased the leaching rate through accelerated reaction kinetics and mass diffusion. XRD and XRF analyses showed that hematite remained dominant, while anatase and quartz were present as minor phases. These findings confirm the need to optimize process parameters so that red mud leaching can become a sustainable alternative for recovering titanium from secondary sources.