Rare Earth Occurrences in Streams of Processing a Phosphate Ore

Abstract

Rare earth elements (REEs) are defined as lanthanides with Y and Sc. Rare earth occurrences including the REE-bearing phases and their distributions, measured by rare earth oxides (REOs), in the streams of processing a phosphate ore were determined by using MLA, the mineral liberation analysis and EPMA, the electron probe microanalysis. The process includes an apatite ore beneficiation by flotation and further processing of the beneficiation concentrate with sulfuric acid. Twenty-six, sixty-two and twelve percent of the total REOs (TREO) contents from the ore end up in the products of beneficiation tailings, phosphogypsum (PG) and phosphoric acid, respectively. Apatite, allanite, monazite and pyrochlore are identified as REE-bearing minerals in the beneficiation process. In the beneficiation tailings, the REEs are mainly distributed in monazite (10.3% TREO), apatite (5.9% TREO), allanite (5.4% TREO) and pyrochlore (4.3% TREO). Gypsum, monazite, apatite and other REE-bearing phases were found to host REEs in the PG and the REEs distributions are 44.9% TREO in gypsum, 15.8% TREO in monazite, 0.6% TREO in apatite and 0.6% TREO in other REE-bearing phases. Perspectives on the efficient recovery of REEs from the beneficiation tailings and the PG are discussed.

Effect of Mineralogy on the Beneficiation of REE from Heavy Mineral Sands: The Case of Nea Peramos, Kavala, Northern Greece

“…Beneficiation of the three commercially extracted heavy minerals, bastnäsite, monazite, and xenotime involves gravity, magnetic, electrostatic, and flotation separation methods with froth flotation being the most commonly applied REE mineral separation operation ( [27][28][29]…”

Rare Earths’ Recovery from Phosphogypsum: An Overview on Direct and Indirect Leaching Techniques

“…Physical and chemical pre-treatment methods have been used to upgrade the low concentrations of REEs present in PG prior to processing. Physical methods such as hydrodynamic, flotation, grinding and high gradient magnetic separation (HGMS) have been reported in the literature [46,47]. In a study by Yang et al [48] four tests of physical enrichments were conducted on PG through treating it by HGMS alone, flotation combined with HGMS or mechanical grinding followed by flotation and HGMS, and hydrodynamic sedimentation followed by HGMS, respectively.…”

“…However, apart from these phases, REEs can also be found as adsorbed ions in PG. REE occurrences in PG were recently investigated by Yang et al [47] by combining mineral liberation analysis (MLA) and electron microprobe analysis (EMA) for mineral analysis and ICP-MS for elemental composition. Their results showed that gypsum (CaSO 4 ) was the dominating mineral phase in PG that contained over 72% of REEs present in the samples.…”

Phosphogypsum Processing for Rare Earths Recovery—A Review

“…Generally, according to these studies REEs occurred as sulphates, carbonates, fluorides and phosphates and also being adsorbed as REEs 3+ ions. Recently, REE occurrences in PG were studied [21] with a European sample. Chemical analysis by ICP-MS showed that all the REEs except Pm exist and La, Ce, Pr, Nd, Sm, Eu, Gd, Dy and Y were found with relatively high concentrations.…”