PREFACE Actinide separation techniques and methods play a very important role in analysis and production of nuclear materials, reprocessing of nuclear fuels, nuclear waste management, and other aspects of the nuclear fuel cycle. Professionals from several disciplines—analytical chemists, chemical engineers, process chemists, etc.—make much use of this technology. This Symposium has been organized about new concepts, new systems, and new developments in actinide separations methodology. Much of the work reported here is based on fundamental actinide chemistry developed since the Manhattan Project days. The chapters in this volume describe ion exchange, solvent extraction, precipitation, pyrochemical, photochemical, and other methods of actinide separations as well as application of these separation methods to power reactor fuel reprocessing and recovery of actinides from waste solutions. The purpose of this Symposium has been to bring together information concerning actinide recovery, partition, and purification on an international basis from various disciplines and viewpoints. The result of this interchange, it is hoped, will be to spark ideas for improvement and development of new separation techniques and methods for all aspects of actinide technology. Vienna, Austria
JAMES D . NAVRATIL
Richland, Washington
W A L L A C E W. SCHULZ
June 20, 1979
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INTRODUCTION Hphe actinide elements consist of naturally occuring thorium, protactinium, and uranium and the synthetic transuranium elements neptunium to lawrencium, inclusive. The actinide elements neptunium to einsteinium, inclusive, are manufactured in weighable quantities by irradiation of uranium in nuclear reactors and are isolated by chemical means. The first chemical process for the isolation of neptunium and plutonium, the Bismuth Phosphate Process, was developed and put into plant-scale operation during World War II. This actinide separations process was replaced by the Redox Process, developed during and after the war. The Redox Process was in turn replaced by the Purex Process, which by now has become the classic method for recovering and purifying uranium, neptunium, and plutonium from irradiated nuclear reactor fuels. Diverse chemical separations processes, specially tailored for the purpose, are used to recover and purify transplutonium elements. Plutonium is manufactured in megagram quantities; neptunium, americium, and curium in kilogram quantities; californium in gram amounts; berkelium in 100-milligram amounts; and einsteinium in milligram quantities. Chemical separations play a key role in the manufacture of actinide elements, as well as in their recovery, and analysis in the nuclear fuel cycle. This collection of timely and state-of-the-art topics emphasizes the continuing importance of actinide separations processes. Berkeley, California
G L E N N T. SEABORG
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