Zirconia Enrichment of Zircon from Arikya, Nasarawa State, Nigeria, by Magnetic and Gravity Separation Processes for Use as Reinforcing Agent in Composite Formulation

Abstract

Acceptable zircon for composite formulation in the aerospace industry requires that the mineral contains a minimum of 65% zirconia (ZrO2). Despite having vast deposits of zircon, Nigeria’s aerospace industry has historically relied primarily on imported mild steel tubes for solid rocket motor cases (SRMCs) construction, resulting in three major challenges: low strength-to-weight ratio, pressure, and temperature containment. In this study, the Arikya zircon deposit located in northern Nigeria was investigated with the aim of upgrading low-grade zircon ore using magnetic and gravity separation processes for use in composite formulation for SRMCs. The dry high-intensity magnetic separator (DHIMS) produced a ZrO2 grade of 52.48%, recovery of 57.99%, and an enrichment ratio of 0.78 with a separation efficiency of 0.56, while the air-floating separator (AFS) generated the highest of 65.52% ZrO2 grade with 70.81% recovery and enrichment ratio of 1.25 with a separation efficiency of 0.25. The ZrO2 content increased from 40.77 to 65.52% after beneficiation. Iron oxide and titanium dioxide contaminants at 0.73 and 0.83% were reduced to 0.66 and 0.54%, respectively, while the specific gravity increased from 4.4 to 4.6 g/cm3. The ZrO2 content and specific gravity were improved to the minimum standard specified for zirconia-reinforced composite application and competed effectively with industrially/globally accepted zircon. These results demonstrated the efficacy of combining DHIMS and AFS to upgrade the low-grade zircon ore from Arikya, Nasarawa State.