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

Date

1987-1

Author

Kizilyalli, Meral
Welch, Alastair J.

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

177
views

0
downloads

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.

Subject Keywords

General Engineering

URI

https://hdl.handle.net/11511/52256

Journal

Journal of the Less Common Metals

DOI

https://doi.org/10.1016/0022-5088(87)90370-5

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

AN EXPERIMENTAL INVESTIGATION OF POLYVINYL-CHLORIDE) EMULSION POLYMERIZATION - EFFECT OF INITIATOR AND EMULSIFIER CONCENTRATIONS ON POLYMERIZATION KINETICS AND PRODUCT PARTICLE-SIZE Karakaş, Gürkan (Wiley, 1989-01-01) Effects of concentration changes in initiator species Na2SO3, (NH4)2S2O8 and CuSO4, and emulsifier, ammonium stearate, on poly(vinyl chloride) (PVC) emulsion polymerization kinetics and on product particle size were experimentally investigated. It was observed that to obtain industrially significant rates and overall conversions, not only an optimum concentration ratio of Na2SO3/(NH4)2S2O8/CuSO 4 must be used, but also the concentrations of these species must be above certain limits. Increasing the concentr...
A Five Layer One-Dimensional PEMFC Model with Detailed Electrode Kinetics Ficicilar, B.; Eroğlu, İnci; Nguyen, T. V. (2010-10-01) In this study, a non-isothermal, two-phase, one-dimensional, and steady state proton exchange membrane (PEM) fuel cell model is developed to investigate the detailed electrode kinetics in the anode and cathode catalytic regions and the effects of these reaction mechanisms on the performance of a PEM fuel cell. Langmuir-Butler-Volmer (LBV) type reaction rate expressions are suggested for both anode and cathode electrochemical reactions. A two-phase energy balance approach is used to catch the thermal transpo...
ELECTROINITIATED POLYMERIZATION OF ACRYLONITRILE YURTTAS, B; Toppare, Levent Kamil; Akbulut, Ural (Informa UK Limited, 1988-01-01) Anionic polymerization of acrylonitrile was achieved by constant-potential electrolysis via direct electron transfer to the monomer. The reduction peak potential in the (C4 H9)4 NBF4 -CH3 CN electrolyte-solvent system was measured by cyclic voltammetry. On the other hand, dimethylformamide-metal salts were not found suitable for the direct electron-transfer process in our system. Polymers produced both anodically and cathodically were found to contain cyclized structures.
A novel synthesis of optically active alpha-amino acids Demir, Ayhan Sıtkı (Walter de Gruyter GmbH, 1997-01-01) A new enantioselective synthesis of alpha- amino acids are described in which the key step is the enantioselective reduction of E, and Z furyl ketone oxime ethers with chiral boron complexes. The chirality of amino acid is fully controlled by appropriate choice of geometrical isomer of the oxime ether.
Fabrication and characterization of p-Si/n-ZnO heterostructured junctions Klason, P.; Rahman, M. M.; Hu, Q. -H.; Nur, O.; Turan, Raşit; Willander, M. (Elsevier BV, 2009-04-01) In this paper ZnO nanorods and nanodots (with and without a SiO2 buffer layer) were grown on p-Si, forming p-n heterojunctions. The nanorod devices showed no visible electroluminescence (EL) emission but showed rectifying behavior. Covering around 60% of the length of the nanorods with PMMA produced an ideality factor of 3.91 +/- 0.11 together with a reverse saturation current of 6.53 +/- 4.2 x 10(-8) A. Up to two orders of magnitude rectification was observed for the current at bias -3 and 3 V. The nanodot...

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.