Journal
SEPARATION AND PURIFICATION TECHNOLOGY
Volume 227, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.seppur.2019.115714
Keywords
Bauxite residue; Rare earth elements; Enrichment; Silica; Acid leaching
Categories
Funding
- National Natural Science Foundation of China [51234008, 51174230]
- Co-Innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources
Ask authors/readers for more resources
Bauxite residue (BR) is a hazardous industrial waste and also becomes an important reserve of rare earth elements (REE). An elegant process for achieving separation of REEs against silica from an iron-removed BR was established in this paper through selective leaching of silica with simultaneous enrichment of REEs. It was found that the phosphoric acid performed better than other acids (HNO3, HCl) for multiple REEs enrichment. The ideal conditions for the leaching process was determined through response surface methodology (RSM) to be H3PO4 concentration of 1.2 mol/L, L/S ratio of 11 mL/g and leaching temperature of 40 degrees C. 82.3% SiO2 in iron-removed BR was leached out while the REEs (La2O3, Ce2O3, Sc2O3 and Y2O3) remained in the leached residue with recovery of more than 98%. La2O3 and Ce2O3 were proved to be in lattice replacement within the acid-resistant pervoskite and thus remained in the leached residue. Only part of Sc2O3 and Y2O3 entered into pervoskite and the remainder was trapped in the aluminosilicate minerals. The enrichment of Sc2O3 and Y2O3 in phosphoric acid leaching process was related to the low acidity of H3PO4 solution.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available