Physical beneficiation of rare earth-bearing ores by Pickering emulsification

Abstract

Abstract A solid-stabilized emulsification process was developed to produce a concentrate of the rare earth element (REE)-bearing minerals bastnasite and monazite from an ore that included gangue minerals such as dolomite, calcite, ankerite, silicate, quartz, pyrite, mica, hematite, and barite. The liberated REE-bearing minerals displayed better affinity for oil droplets than the gangue due to differences in surface wettability and eventually adsorbed to the oil-water interface whereas the gangue remained in the water phase. We studied the behavior of the REE-bearing ore in a Pickering emulsification system. We, consequently, determined the ability of Pickering emulsification to separate and concentrate REE-bearing minerals. The enrichment ratio after a single-stage emulsification was 2.9, with a recovery exceeding 50%, and with no need to adjust the pH and/or apply a surface modifier.