Chemical pretreatment of nuclear wastes refers to the sequence of separations processes used to partition such wastes into a small volume of high-level waste for deep geologic disposal and a larger volume of low-level waste for disposal in a near-surface facility. Pretreatment of nuclear wastes now stored at several U. S. Department of Energy sites ranges from simple solid-liquid separations to more complex chemical steps, such as dissolution of sludges and removal of selected radionuclides, e. g. , 90Sr, 99Tc, 137CS, and TRU (transuranium) elements. The driving force for development of chemical pretreatment processes for nuclear wastes is the economic advantage of waste minimization as reflected in lower costs for near-surface disposal compared to the high cost of disposing of wastes in a deep geologic repository. This latter theme is expertly and authoritatively discussed in the introductory paper by J. and L. Bell. Seven papers in this volume describe several separations processes developed or being developed to pretreat the large volume of nuclear wastes stored at the US DOE Hanford and Savannah River sites. These papers include descriptions of the type and amount of important nuclear wastes stored at the Hanford and Savannah River sites as well as presently envisioned strategies for their treatment and final disposal. A paper by Strachan et al. discusses chemical and radiolytic mechanisms for the formation and release of potentially explosive hydrogen gas in Tank 241-SY-101 at the Hanford site.

Radioactive wastes resulting from over 40 years of production of nuclear weapons in the U. S. are currently stored in 273 underground tanks at the U. S. Department of Energy Hanford site, Idaho National Engineering and Environmental Laboratory, Oak Ridge Reservation, and Savannah River site. Combined, tanks at these sjtes contain approximately 94,000,000 gallons of waste in a variety of forms including liquid, concrete-like salt cake, and various sludges. More than 730,000,000 curies of several radioactive isotopes are present in the underground tanks. Certainly, one of the greatest challenges facing the U. S. Department of Energy is how to characterize, retrieve, treat, and immobilize the great variety of tank wastes in a safe, timely, and cost-effective manner. For several years now, the U. S. Department of Energy has initiated and sponsored scientific and engineering studies, tests, and demonstrations to develop the myriad of technologies required to dispose of the radioactive tank wastes. In recent times, much of the Department of Energy R&D activities concerning tank wastes have been closely coordinated and organized through the Tanks Focus Area (IF A); responsibility for technical operations of the TF A has been assigned to the Pacific Northwest National Laboratory.

Macrocyclic Chemistry: Current Trends and Future Perspectives illustrates essential concepts in this expanding research field covering both basic and applied studies. Written by well-known experts from around the world, the topics of the chapters range from new macrocyclic architectures with different functions and self-assembly processes through to the modeling and dynamics of such systems. The content also reflects on application possibilities in analytical chemistry, separation processes, material preparation and medicine. Thus this book serves as a creative source of research strategies and methodic tools. Providing an excellent overview of the field, this book will be a valuable resource for researchers in industry and academic institutions as well as for teachers of science and graduate students. This book is devoted to the long-standing tradition of the International Symposia on Macrocyclic Chemistry (ISMC) and published to coincide with the 30th meeting, Dresden, Germany.

Extractions of Metals from Soils and Waters represents a new emphasis in the series Modern Inorganic Chemistry, namely the impact inorganic chemistry can have on the environment. Also, this is the first volume ever to introduce the reader to all aspects of heavy metal extraction. While the primary emphasis is on complexation chemistry, attention is also paid to phase transfer aspects. Particular methods of note include electrokinetics, phytoremediation, and sensors. Aimed primarily at chemists, this book will also appeal to engineers, plant biochemists, environmental health specialists, and practitioners or students of environmental law.

This thematic issue devoted to 'Template Effects and Molecular Organization' is based on a special symposium recently organized by the American Chemical Society in Philadelphia. The authors contributed oral presentations and are experts in their fields. Each chapter is fully referenced Contains comprehensive reviews written by leading experts in the field Includes new information on the important advances in inorganic and bioinorganic chemistry

The purpose of this technical seminar was to evaluate the present state of the art in matter of advanced separation techniques like solvent extraction, ion-exchange, chemical precipitation, membrane and electrical processes for the treatment of radioactive liquid waste and a selection of some specific industrial non-radioactive effluents. Through this initiative, the organisers aimed at promoting the exchange of information between scientists from various origins (universities, research centres and industries) while contributing to the necessary overcoming of the artificial barriers which too often limit the "technology transfer" between the nuclear and non-nuclear sectors. Vll CONTENTS PREFACE ........................................ V ABBREVIATIONS ...................................... xiv OPENING SESSION WELCOME ADDRESS C. MANCINI (ENEA) .................................... 3 OPENING ADDRESS S. FINZI (CEC) ....................................... 7 AREAS WHERE ADVANCED SEPARATION TECHNIQUES ARE DESIRABLE G. GROSSI (ENEA), L. CECILLE (CEC) ....................... 11 REVIEW OF NEW EXTRACT ANTS POTENTIALLY APPLICABLE TO THE PROCESSING OF RADIOACTIVE LIQUID WASTES (Summary) P.R. DANESI, International Atomic Energy Agency, Vienna, Austria . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 . . . . . . . . . .

Readings from the Treatise on Geochemistry offers an interdisciplinary reference for scientists, researchers and upper undergraduate and graduate level geochemistry students that is more affordable than the full Treatise. For professionals, this volume will provide an overview of the field as a whole. For students, it will provide more in-depth introductory content than is found in broad-based geochemistry textbooks. Articles were selected from chapters across all volumes of the full Treatise, and include: The Origin and Earliest History of the Earth, Compositional Evolution of the Mantle, Evolution of Sedimentary Rocks, Soil Formation, Geochemistry of Groundwater, Geologic History of Seawater, Hydrothermal Processes, and Biogeochemistry of Primary Production in the Sea. Comprehensive, interdisciplinary and authoritative content selected by leading subject experts Robust illustrations, figures and tables Affordably priced sampling of content from the full Treatise on Geochemistry

In recent times the nuclear industry has thrown up challenges which cannot be met by the application of conventional civil and materials engineering knowledge. The contributions in this volume investigate all aspects of cement performance. The scope of the papers demonstrate the current balance of activities which have as their objective the elucidation of kinetics and immobilization, determining material interactions and of assessing future performance. The papers reflect the varied goals of the sponsors who include national governments, the Commission of the European Communities and the nuclear industries, coming together to keep each other at the forefront of advanced technology.

Separation Techniques in Nuclear Waste Management is an up-to-date, comprehensive survey of processes for separation of nuclear wastes. Comprised of articles by scientists and engineers at universities and national laboratories in the U.S. and overseas, the book provides excellent reference information for individuals working in nuclear waste management. Specifically, the book covers current separation technologies and techniques for waste liquid, solid, and gas streams that contain radionuclides. Such wastes are typical of those produced as a result of nuclear materials processing and spent fuel reprocessing. Chapters on promising new technologies and state-of-the-art processes currently in use provide valuable information for design engineers, as well as for research scientists. The articles in Separation Techniques in Nuclear Waste Management are brief and concise - designed for quick access to pertinent information. Many of the contributors are leaders in their fields. It is the most current survey available of the latest nuclear waste management techniques.