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Proceedings of an Advisory Group Meeting Paris, 5-8 June 1979 PRODUCTION OF YELLOW CAKE AND URANIUM FLUORIDES fj£±\ ^tyr/ INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1980 PRODUCTION OF YELLOW CAKE AND URANIUM FLUORIDES The following States are Members of the International Atomic Energy Agency: AFGHANISTAN HOLY SEE PHILIPPINES ALBANIA HUNGARY POLAND ALGERIA ICELAND PORTUGAL ARGENTINA INDIA QATAR AUSTRALIA INDONESIA ROMANIA AUSTRIA IRAN SAUDI ARABIA BANGLADESH IRAQ SENEGAL BELGIUM IRELAND SIERRA LEONE BOLIVIA ISRAEL SINGAPORE BRAZIL ITALY SOUTH AFRICA BULGARIA IVORY COAST SPAIN BURMA JAMAICA SRI LANKA BYELORUSSIAN SOVIET JAPAN SUDAN SOCIALIST REPUBLIC JORDAN SWEDEN CANADA KENYA SWITZERLAND CHILE KOREA, REPUBLIC OF SYRIAN ARAB REPUBLIC COLOMBIA KUWAIT THAILAND COSTA RICA LEBANON TUNISIA CUBA LIBERIA TURKEY CYPRUS LIBYAN ARAB JAMAHIRIYA UGANDA CZECHOSLOVAKIA LIECHTENSTEIN UKRAINIAN SOVIET SOCIALIST DEMOCRATIC KAMPUCHEA LUXEMBOURG REPUBLIC DEMOCRATIC PEOPLE'S MADAGASCAR UNION OF SOVIET SOCIALIST REPUBLIC OF KOREA MALAYSIA REPUBLICS DENMARK MALI UNITED ARAB EMIRATES DOMINICAN REPUBLIC MAURITIUS UNITED KINGDOM OF GREAT ECUADOR MEXICO BRITAIN AND NORTHERN EGYPT MONACO IRELAND EL SALVADOR MONGOLIA UNITED REPUBLIC OF ETHIOPIA MOROCCO CAMEROON FINLAND NETHERLANDS UNITED REPUBLIC OF FRANCE NEW ZEALAND TANZANIA GABON NICARAGUA UNITED STATES OF AMERICA GERMAN DEMOCRATIC REPUBLIC NIGER URUGUAY GERMANY, FEDERAL REPUBLIC OF NIGERIA VENEZUELA GHANA NORWAY VIET NAM GREECE PAKISTAN YUGOSLAVIA GUATEMALA PANAMA ZAIRE HAITI PARAGUAY ZAMBIA PERU The Agency's Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is "to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world". (g) IAEA, 1980 Permission to reproduce or translate the information contained in this publication may be obtained by writing to the International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria. Printed by the IAEA in Austria November 1980 PANEL PROCEEDINGS SERIES PRODUCTION OF YELLOW CAKE AND URANIUM FLUORIDES PROCEEDINGS OF AN ADVISORY GROUP MEETING ORGANIZED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY AND HELD IN PARIS, 5-8 JUNE 1979 INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 1980 PRODUCTION OF YELLOW CAKE AND URANIUM FLUORIDES IAEA, VIENNA, 1980 STI/PUB/553 ISBN 92-0-041080-4 FOREWORD Several tens of thousands of tonnes of uranium are currently produced per year in the form of 'yellow cake' from over 50 active ore processing plants. In addition there have been a number of plants which have been producers but have become inactive for various reasons over the past two decades, and also a number which are planned to come into operation in the not too distant future. It is therefore not surprising that scientists and engineers engaged in this industry and the research associated with its development have produced many publications describing the overall hydro-metallurgical technology involved and the operating flowsheets of many ore processing plants. However, it is surprising to discover within this literature how little has been devoted to the detailed description of the specific aspects of the processes associated with the actual 'yellow cake' end of the operation. Consideration was therefore given to convening a meeting with the aim of bringing out some of this knowledge and experience and discussing the problems associated with this part of the operation. The basic objective of the processes used for 'yellow cake' preparation is to prepare a uranium concentrate. However, the specifications of the product, which play a major role in determining the conditions used in those processes, are largely determined by the refining and conversion facility. It was therefore apparent that the subject of 'yellow cake' preparation could not be adequately covered in isolation. In addition, although descriptions of refining and conversion processes have appeared, there has been no previous IAEA meeting of experts to consider these subjects. The IAEA thus considered it appropriate to convene an Advisory Group meeting to consider the total technology of that part of the fuel cycle concerned with 'yellow cake' preparation, its refining and conversion to uranium fluorides. At the invitation of the Commissariat a l'Energie Atomique the meeting was held in Paris from 5 to 8 June 1979. A total of 46 participants from 18 countries and one international organi­ zation took part in the meeting, 20 papers and supplementary contributions being presented. Although a number of the papers cover a wide range of the subject matter, so far as possible the papers have been arranged in the Proceedings to follow the natural sequence of the operations and processes involved in taking the uranium from its original source through the various stages of concentration, purification, refining and, finally, conversion to fluorides. The technical sessions concluded with a Panel summary and discussion, the substance of which is also reproduced. The Agency wishes to thank all the scientists and engineers who participated in the meeting. Thanks are especially due to the Panel Chairman, Dr. H. Page, and the Chairmen of the technical sessions: Dr. A.W. Ashworth, Mr. J. Craig, Mr. G. Lyaudet and Dr. S.A. Young. The success of the meeting owes much to Mr. G. Lyaudet who was responsible for the detailed arrangements in Paris. The Agency also wishes to record its appreciation to the French authorities for hosting the meeting and to COGEMA and COMURHEX for the cooperation and hospitality extended to the participants. EDITORIAL NOTE The papers and discussions have been edited by the editorial staff of the International Atomic Energy Agency to the extent considered necessary for the reader's assistance. The views expressed and the general style adopted remain, however, the responsibility of the-named authors or participants. In addition, the views are not necessarily those of the governments of the nominating Member States or of the nominating organizations. Where papers have been incorporated into these Proceedings without resetting by the Agency, this has been done with the knowledge of the authors and their government authorities, and their cooperation is gratefully acknowledged. The Proceedings have been printed by composition typing and photo-offset lithography. Within the limitations imposed by this method, every effort has been made to maintain a high editorial standard, in particular to achieve, wherever practicable, consistency of units and symbols and conformity to the standards recommended by competent international bodies. The use in these Proceedings of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of specific companies or of their products or brand names does not imply any endorsement or recommendation on the part of the IAEA. Authors are themselves responsible for obtaining the necessary permission to reproduce copyright material from other sources. CONTENTS Ore processing and refining of uranium in India 1 S. Sen, T.K.S. Murthy Technological studies on the Manisa-Koprubaji uranium ores of Turkey 11 U. Sagdik Recuperation de uranio desde soluciones de lixiviacion de cobre de la mina Chuquicamata Sur 19 N. Andalaft, R. Soto Impurities in uranium process solutions 29 D. W. Boy dell Production of pure yellow cake by ion exchange processes employing sulphate elution 51 A. Himsley Caractensticas de suspensiones de uranato amonico 63 J.L. Merino Obtencion de concentrados de uranio-Purlex de baja ley en sulfatos 83 B. Rodriguez A review of United States yellow cake precipitation practice 101 J.E. Litz, R.B. Coleman Purification et concentration des solutions uraniferes dans les usines de la Societe industrielle des minerals de l'Ouest 119 G. Vollerin Production of uranium oxide concentrates by the Nuclear Fuels Corporation of South Africa 129 S.A. Young Практика получения желтого кека 141 Б.Бошина (Yellow cake product practice, В. Bosina, CSSR) Australian experience in the production of yellow cake and uranium fluorides 149 P.G. Alfredson Informe sobre evolucion у perspectivas en Espana 179 P. Gasos The quality aspects of uranium mill and conversion plant technology 189 /. W. Craig Du concentre d'uranium a l'hexafluorure 201 A. Perez Uranium refining in South Africa — The production of uranium trioxide considering raw material properties and nuclear purity requirements 229 R.P. Colborn, D.L.G. Bayne, M.N. Slabber A review and update of refining practice in Canada 261 A.W. Ashbrook, B.C. Smart United Kingdom experience of production of uranium fluorides 289 H. Page Studies for producing UF6 fom UF4 nH20 in Japan 309 S. Takenaka, T. Nagasaki Refining of yellow cake by solvent extraction — Pakistan status report .... 329 M. Yunus, A. Muzaffar, M.T. Qureshi, N.K. Qazi, J.R. Khan, N.A. Chughtai, S.M.H. Zaidi Yellow cake produced from Swedish uranium ores (short communication) 341 A. Andersson A note on uranium in the United States of America (short communication) 345 F.E. McGinley Panel Summary .. 347 List of Participants 351 ORE PROCESSING AND REFINING OF URANIUM IN INDIA S. SEN, T.K.S. MURTHY Chemical Engineering Division, Bhabha Atomic
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  • Journal of Luminescence 210 (2019) 425–434

    Journal of Luminescence 210 (2019) 425–434

    Journal of Luminescence 210 (2019) 425–434 Contents lists available at ScienceDirect Journal of Luminescence journal homepage: www.elsevier.com/locate/jlumin Insight into the effect of A-site cations on structural and optical properties of T RE2Hf2O7:U nanoparticles ∗ Maya Abdoua, Santosh K. Guptaa,b, Jose P. Zunigaa, Yuanbing Maoa,c, a Department of Chemistry, University of Texas Rio Grande Valley, 1201 West University Drive, Edinburg, TX, 78539, USA b Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India c School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, 1201 West University Drive, Edinburg, TX, 78539, USA ARTICLE INFO ABSTRACT Keywords: A2B2O7 type pyrochlores have been recently proposed as a potential nuclear waste host due to their many Uranium interesting properties. To assess and understand the performance of these compounds as nuclear waste hosts, the Pyrochlore speciation and structural investigations on actinide-doped RE2Hf2O7 are needed since both are imperative from Phase-transition their application perspective. In this work, we investigated the effect of uranium doping at different con- Luminescence centrations in the range of 0–10% on the structural and optical properties of RE Hf O :U (RE = Y, Gd, Nd, and Cotunnite 2 2 7 Lu) nanoparticles (NPs). The Y2Hf2O7 NPs exist in slightly disordered pyrochlore structure and the extent of disordering increases as a function of uranium doping while the structure reaches a cotunnite phase at 10.0% doping level. The Nd2Hf2O7 NPs also exist in a distorted pyrochlore structure and their distortion increases with increasing uranium doping inducing a phase transition into a disordered fluorite structure at 10.0% uranium doping.