مرکز منطقه ای اطلاع رساني علوم و فناوري - Nickel recovery from lateritic ores via bioleaching

Abstract :

Upon progress of technology, nickel has been considered as an important raw material for development of new products. Ore deposits with only 1-3% Ni content are suitable for production. About 72% of the world s nickel resources are laterites. The remaining 28% are sulphides. However, about 58% of the world’s primary nickel production comes from nickel sulphide and about 42% of mined nickel comes from nickel laterite deposits. Moreover decrease in sulphide nickel reserves makes lateritic deposits come to the forefront in nickel production. The most common technique in processing of lateritic nickel ores involves traditional mining of the ore, crushing and grinding of the ore after its removal from the ore deposit and the use of pyrometallurgical and/or hydrometallurgical techniques to extract metals from the ore. In traditional extraction of metals from ores, high temperatures (pyrometallurgy) and chemicals (hydrometallurgy) are used which have detrimental effects on environment and human health. Consequently, biological extraction methods gained significant importance due to increase in biotechnological developments and found a growing application area in the mining industry for the last 50 years. Bioleaching is a simple, economical and environmentally friendly technique in leaching of metals from low grade ores. As lateritic nickel ores possess very high amounts of iron, H2SO4 consumption in hydrometallurgical processes increases significantly. The use of bioleaching technique for the extraction of nickel from lateritic nickel ores could reduce the inferior economical effects of acid usage and make the process to be performed in a more controlled way. In this paper, recent developments and bioleaching applications in the nickel recovery from lateritic ores were investigated.