Pengaruh Leaching Asam dan Basa pada Pemungutan Logam Tanah Jarang dari Abu Layang Batubara Indonesia
Jihan Azzahra Widowati, Dr. Widya Rosita, S.T., M.T., IPU.; Prof. Himawan Tri Bayu Murti Petrus, S.T., M.E., D.Eng.
2023 | Skripsi | FISIKA TEKNIK
Rare Earth Element (REE) are a group of seventeen chemical elements in the periodic table which have numerous applications in modern life. The emergence of concerns about the availability of rare earth reserves have led to an enormous rise in global exploration to obtain economical rare earth resources. This research will compare the recovery of REE from Indonesian coal fly ash using alkaline and acid leaching methods.
The recovery of REE from fly ash through alkaline leaching includes several stages. The first stage is the destruction of the aluminosilicate glass phase contained in the fly ash and the second stage is the extraction of REE from the desilicated residue by the acid leaching process. Variations made are the temperature of the reaction and the concentration of the base solution. The process of extracting REE from fly ash can also be carried out by leaching acid only at a certain concentration and temperature. X-Ray Fluorescence (XRF) analysis of REE, Si, Al, Fe, Ca, and Mg was performed to evaluate the efficiency of the base leaching process in dissolving aluminosilicate glass and the ability of acid leaching to extract REE.
The optimum conditions for the alkaline digestion process were NaOH concentration of 9,5 M, reaction temperature of 75°C, L/S ratio of 10 mL/g, stirring speed of 400 rpm, and reaction time of 90 minutes. At optimal conditions, the alkaline digestion process can dissolve up to 72% aluminosilicate glass and enrich the REE content in the desilicated residue by 1,73. Recovery of REE with desilicated residue feed through HCl leaching reached 87,914%. However, when compared to the recovery of REE with acid leaching alone, the efficiency value obtained is higher, reaching 90,513%.
Kata Kunci : Logam Tanah Jarang, abu layang batubara, digesti, leaching HCl