A new method for processing of monazite and examination of the products by X-ray analysis

Kizilyalli, Meral
Welch, Alastair J.
Sintering reactions of lanthanide orthophosphates with Na2CO3 gave the expected products (Na3PO4 and Ln2O3) with stoichiometric amounts of Na2CO3. When less than the theoretical amounts of Na2CO3 were used, two intermediate products eventually characterized by X-ray diffraction as Na3Ln(PO4)2 and Ln3PO7 were detected. Application of the sintering method to naturally occurring phosphates, particularly the mineral monazite, proved to be very successful. By using the optimum amount of Na2CO3 to form Na3Ln(PO4)2, and dissolving this product in dilute hydrochloric acid, it was possible to break down monazite and to separate the basic oxide content into ceria plus thoria and sesquioxides.
Journal of the Less Common Metals


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Citation Formats
M. Kizilyalli and A. J. Welch, “A new method for processing of monazite and examination of the products by X-ray analysis,” Journal of the Less Common Metals, pp. 137–145, 1987, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52256.