Proof-of-Concept Study on Extraction of Nickel from Low-Grade Ultramafic Nickel Concentrates

The chapter focuses on a proof-of-concept study to extract nickel from low-grade ultramafic nickel concentrates, which are primarily composed of pentlandite, pyrrhotite, and serpentine. The authors developed a low-temperature thermal treatment process to convert serpentine and extract nickel into large FeNi particles with minimal sulfur dioxide emissions. The study involved two-stage thermal treatment tests on ultramafic nickel sulfide concentrates, resulting in over 90% nickel extraction into the FeNi phase with a Ni grade of over 20%. The characteristic FeNi particle size was found to be 40–48 μm. The research highlights the feasibility of this method for sustainable and economic utilization of low-grade ultramafic nickel resources, paving the way for future optimization studies in thermal upgrading and physical separation of FeNi particles.