STUDY OF BENEFICIATION OF BAUXITE WITH HIGH SILICA CONTENT FROM TAYAN - WEST KALIMANTAN BY REVERSE CATIONIC FLOTATION METHOD

• Main Author: PALIT (NIM : 22114024), CHRISTIN
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/26267
• Institution: Institut Teknologi Bandung

One of mineral resources that Indonesia has is bauxite. Indonesia has substantial <br /> <br /> bauxite reserves, especially in West Kalimantan with a total reserve of <br /> <br /> approximately 1.1 billion tonnes of ore (ESDM, 2012). Based on U.S. Geological <br /> <br /> Survey data in 2016, bauxite deposit in Indonesia ranks the 6th largest in the world. <br /> <br /> Bauxite deposit in Indonesia is classified as the lateritic type which is the result of <br /> <br /> weathering and secondary enrichment of high-feldspar igneous rocks. Bauxite, <br /> <br /> which is the main ore of alumina, is a major component in the aluminum industry. <br /> <br /> Only bauxite ores that fulfill the requirements to be feed for Bayer process can be <br /> <br /> used for the alumina extraction from bauxite. The bauxite ore that can be used as a <br /> <br /> feed for Bayer process must contain > 51% Al2O3, < 7% SiO2, and having <br /> <br /> Al2O3/SiO2 ratio of > 10. <br /> <br /> This study implements reverse flotation as an alternative beneficiation method for <br /> <br /> bauxite processing. This study is aimed to decrease silica content and increase <br /> <br /> alumina content in bauxite ore to improve its qualification as feed for Bayer <br /> <br /> process. The experiments were carried out in a 1375 mL flotation cell. <br /> <br /> Dodecylamine (DDA) and AERO 3000C were used as the collector, starch as the <br /> <br /> depressant, and Dowfroth 1012 as frother. The overall experiments were conducted <br /> <br /> at 25%-solid (w/w). Alumina and silica content of the flotation products were <br /> <br /> analyzed by XRF. The results of XRF of flotation products showed that there were <br /> <br /> an increase in alumina content and decrease in silica content. The optimum pH <br /> <br /> range of bauxite flotation using DDA and AERO 3000C as collectors can be <br /> <br /> achieved at pH 4 – 10. From the results of the experiments, it can be seen that the <br /> <br /> flotation performance using DDA was better than that using AERO 3000C, <br /> <br /> indicated by higher Al2O3 content at 61.4%. The increase of collector dosage at <br /> <br /> pH 10 yielded high Al2O3 content at 62% and low SiO2 at 29.4% with 50.44% <br /> <br /> recovery of Al2O3 obtained at dosage of collector at 500 g/ton. Higher Al2O3 content <br /> <br /> obtained without the addition of depressant at 66.8% with SiO2 content of 23.5%. <br /> <br /> While for the size fraction variation, it can be seen that more effective separation <br /> <br /> occurred in the finer particle, indicated by the increasing alumina content and <br /> <br /> decreasing silica content. Optimum condition in this study were achieved at 400 <br /> <br /> g/ton of DDA dosage, 400 g/ton of depressant dosage and size fraction of particle <br /> <br /> -44 µm at pH 10 with alumina content of 79.1% and high silica content of 8.89%.