Comprehensive utilization of Philippine laterite ore, part 1: Design of technical route and classification of the initial ore based on mineralogical analysis

Nickel, cobalt, iron, and chromium are potentially valuable metals contained in laterite ores. Mineralogical analysis results revealed that the laterite from the Philippines contained predominantly fine iron oxide/oxyhydroxide, as well as a small amount of slightly coarse chromite and gangue mineral aggregates. Additionally, the coarse cores of minerals were closely surrounded and adhered by a matrix of fine minerals. The chemical components were closely related to the particle sizes of constituent minerals. Based on these findings, a classification method was devised and three samples with different components were obtained under the proposed optimal scheme. About 50% of Mg and Si were removed from the fine fraction (S1) and more than 85% of Fe and Ni distributed in it. The other two samples are Co-riched and the content in the intermediate fraction (S2) and the coarse fraction (S3) was 0.22% and 0.28%, respectively. Cr in S2 was as high as 6.75%. A technical route was designed for processing these three samples and the preliminary tests indicate that the recoveries of Fe, Ni, Co and Cr can reach about 94%, 85%, 70% and 30%, respectively; Fe content in the prepared iron concentrate is over 61% and Cr content in the obtained Cr-riched residue is above 12%. Consequently, comprehensive utilization of Philippine laterite ore can be realized following the proposed route.