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Australia has abundant deposits of laterite ores which role in production of nickel is increasing with rising demand for nickel and depletion of sulphide reserves.Laterite ores cannot be efficiently upgraded prior to pyrometallurgical or hydrometallurgical processing what leads to significant challenges in extraction of nickel. The PhD project was undertaken within the ARC (Australian Research Council) Discovery Grant (Project No. DP1094880) which examined a novel approach to processing of laterite ores based on the selective reduction of the ore and extraction of nickel by carbonylation of the selectively reduced ore. Selective reduction of the laterite ore was studied by J. Yang in his PhD project (Yang, 2014). The ultimate aim of this project was to establish the feasibility of extraction of nickel by carbonylation of selectively reduced laterite ore. The project undertook a systematic study of carbonylation of pure nickel and iron, and carbonylation of selectively reduced laterite ore to develop a further understanding of carbonylation reactions and extraction of nickel from laterite ore by carbonylation.Specific objectives of this study included:1) to study the effects of reaction parameters on carbonylation of nickel and iron, including reaction temperature (80-100 °C), carbon monoxide (gauge) pressure (0-56atm), gas flow rate (0.14-0.50 L/min), nickel mass (0.8-3.2g) and particle sizes (0.29 – 2.67 µm), and the effect of sulphur-containing catalysts (sulphur, iron sulphide and hydrogen sulphide);2) to study the non-catalytic and catalytic carbonylation of laterite ores; the impacts of reduction conditions; and effects of reaction parameters;3) to develop further understanding of kinetics and mechanisms of carbonylation processes.Pure metals and nickel-iron mixture were prepared by the reduction of associated oxides by hydrogen at 500 °C (gas flow rate 1.0 L/min); the degree of reduction of oxides was over 98%. Two types of Australian laterite ores supplied by