THE STUDY OF FERRONICKEL PARTICLE FORMATION FROM LIMONITE NICKEL ORE AT 1100-1300OC BY USING COAL AS REDUCTANT WITH NA2SO4 AND H3BO3 AS ADDITIVES

• Main Author: Hasina Nizami, Zahra
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49144
• Institution: Institut Teknologi Bandung

Nickel is one of the elements that has been widely used in numerous industries, such as stainless steel, superalloy, coating, and electrical vehicle’s batteries. Nickel ore has been found in Indonesia as lateritic nickel ore. There are two types of lateritic nickel ore, i.e. saprolite and limonite. The reserve of limonite ore is 2-3 times greater than that of saprolite ore. The cost of limonite ore is also cheaper. The common technology for treating laterite nickel ore via pyrometallurgy is Rotary Kiln – Electric Furnace (RKEF). However, this process requires a lot of energy as it operates at high temperature (1400oC-1700oC). In this research, the effect of reduction temperature and the effect of Na2SO4 and H3BO3 on the formation of ferronickel particle from limonite ore were studied at lower temperature (1100oC-1300oC). Limonite nickel ore, coal, Na2SO4, and H3BO3 were agglomerated to form three types of briquettes, namely briquette A (addition of 10% coal), briquette B (addition of 10% coal and 10% Na2SO4), and briquette C (addition of 10% coal, 10% Na2SO4, and 5% H3BO3). The reduction process was carried out at temperatures of 1100oC, 1150oC, 1200oC, 1250oC, and 1300oC by using horizontal tube furnace and under argon atmosphere for 60 minutes. The reduced briquettes were then observed using optical microscope, and then processed using ImageJ software to measure the ferronickel particles. The briquettes which have been reduced at 1250oC were analyzed using Scanning Electron MicroscopeEnergy Dispersive X-ray Spectroscopy (SEM-EDS). The results of this study indicate that the rising of temperature from 1100oC to 1300oC will increase the size of ferronickel particles. In briquette A (addition of 10% coal), the largest ferronickel particle increased by 133.75%, which was from 61.1 ?m to 142.82 ?m. In briquette B (addition of 10% coal and 10% Na2SO4), the largest ferronickel particle increased by 172.14%, which was from 91.11 ?m to 247.95 ?m. In briquette C (addition of 10% coal, 10% Na2SO4, and 5% H3BO3), the largest ferronickel particle increased by 265.64%, which was from 128.45 ?m to 469.67 ?m. In the reduction temperature of 1250oC, briquette A (addition of 10% coal) produced ferronickel with nickel content of 3.55%, iron 94.58%, and sulfur 0.31%, briquette B (addition of 10% coal and 10% Na2SO4) produced ferronickel with nickel content of 4.12%, iron 83.79%, and sulfur 1.55%, while briquette C (addition of 10% coal, 10% Na2SO4, and 5% H3BO3) produced ferronickel with nickel content of 4.78%, iron 92.93%, and sulfur 0.13%.