STUDY ON THE EFFECT OF FERRONICKEL ROASTING ON THE EFFECTIVENESS LEACHING OF FERRONICKEL IN HYDROCHLORIC ACID SOLUTIONS AT ATMOSPHERIC PRESSURE

• Main Author: Gorga A Tambunan, Christofel
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/76258
• Institution: Institut Teknologi Bandung

Ferronickel (FeNi) is a nickel-iron alloy with a nickel content of 15–25%. Most of the FeNi is used as a raw material for stainless steel. Recently, the market of nickel is increasing to fullfill the demand of raw materials for lithium ion-batteries. FeNi can be utilized as a raw material source for battery cathode by extracting the iron, nickel, and cobalt from the FeNi. Iron can be processed into iron phosphate as the cathode raw material for LiFePO4 (LFP) batteries, while nickel can be converted into nickel sulfate as cathode raw material for lithium nickel-manganese-cobalt oxide (NMC) batteries. In this research, the metal extraction from FeNi was studied using roasting and leaching methods in hydrochloric acid solution without converting the FeNi to matte prior to leaching stage. This study is part of the development of a process for converting FeNi to iron phosphate and nickel sulfate, which is expected to be more straightforward compared to current commercial techniques involving the conversion of FeNi to matte. A series of roasting experiments followed by leaching at atmospheric pressure in HCl solution were carried out to study the effects of roasting temperature (300-600 °C), roasting time (30-120 minutes), hydrochloric acid concentration in leaching stage (5.0-6.5 M), and leaching temperature (70-100 °C) on the extraction percentages of nickel, cobalt, iron, manganese, and chromium. Each leaching experiment was carried out for 3 h with an agitation speed of 300 rpm, and solid-liquid ratio of 25 g/L. The leaching kinetics of FeNi was studied at a hydrochloric acid concentration of 5 M and temperatures of 70, 80, 90, and 100 °C. The leaching kinetics of FeNi was studied by using shrinking particle models (SPM). The experimental results show that the percentage of metal extraction decreases with increasing roasting temperature from 300 to 600 °C. The percentages of Fe and Ni extraction relatively did not change with increasing roasting time from 30 to 120 minutes at 300 oC. The percentage of Ni extraction tended to decrease as the concentration of HCl increased from 5 M to 6 M, while the extraction percentages of Fe and Co did not change significantly. Extraction percentages of Fe, Ni, Co, Cr and Mn increase with increasing leaching temperature from 70 to 100 °C. The highest extraction percentages of Fe, Ni, and Co were obtained at a roasting temperature of 300 °C, a roasting time of 30 minutes, HCl concentration of 5 M, a leaching temperature of 100 °C, a particle size fraction of -14+20# (841-1410 ?m), a S/L ratio of 25 g/L, and a stirring speed of 300 rpm for 3 hours, that resulting in an extraction of 98.33% Fe, 100% Ni and 100% Co. The results of kinetic analysis with SPM revealed that the leaching rate of FeNi is controlled by a chemical reaction at the interface with an activation energy of 78.13 kJ/mol.