Recovery and Refining of Precious Metals


Book Description

This book is the product of 50+ years of hands-on physiochemical work with both ferrous and nonferrous metals and with the metallurgy of refining, extracting, and casting. Its purpose is to cover the various methods of recovery and refining of precious metals. Both primary sources (placer gold, black sand, and ores) and secondary sources (scrap jewelry, electronic scrap, old films, buffings, spent plating and stripping solutions, catalytic automobile converters, and old eyeglass frames) are covered. The information contained in this volume is very basic and is intended for hands-on application and use. It is for nonchemist and chemist alike. I will not discuss the mathematical formulas for the various chemical reactions that take place-I leave them to the reader who wants to increase his working knowledge and understanding of chemistry. There are many courses offered in chemistry and extractive metallurgy, as well as a number of books available for self-study. The purpose of this book is to teach you how to perform various extractive, refining, and testing operations on precious metals (in various forms and states), with a resulting end product. You will learn how to perform operations in assaying and extraction, qualitative analysis, quantitative analysis, testing, classifying, and concentration-some of a purely mechanical nature, some of a chemical nature.




Biosorption for Wastewater Contaminants


Book Description

Pollution due to various anthropogenic activities continues to increase. In terms of water pollutants, organic and inorganic pollutants are the most problematic. Although several measures have been proposed and implemented to prevent or reduce contamination, their increased concentration in water bodies has created serious concerns. Over the years, the problem has been aggravated by industrialization, urbanization and the exploitation of natural resources. The direct discharge of wastewater contaminants and their geographical mobilization have caused an increase in concentration in ground, surface, fluvial and residual waters. Extensive information about detection and disposal methods is needed in order to develop technological solutions for a ­variety of environments, both urban and rural. This book provides up-to-date information on wastewater contaminants, aimed at researchers, engineers and technologists working in this field. Conventional physicochemical techniques used to remove contaminants from wastewater include ion exchange, precipitation, degradation, coagulation, coating, membrane processes and adsorption. However, these applications have technological and economic limitations, and involve the release of large amounts of chemical reagents and by-products that are themselves difficult to remove. Biosorption - the use of organically generated material as an adsorbent – is attracting new research and scholarship. Thermally-treated calcined biomaterials may be treated to remove heavy metals from wastewater. To ensure the elimination of these contaminants, existing solutions must be integrated with intelligent biosorption functions. Biosorption for Wastewater Contaminants will find an appreciative audience among academics and postgraduates working in the fields of environmental biotechnology, environmental engineering, wastewater treatment technology and environmental chemistry.




Gold Refining


Book Description




Metal Sustainability


Book Description

The sustainable use of natural resources is an important global challenge, and improved metal sustainability is a crucial goal for the 21st century in order to conserve the supply of critical metals and mitigate the environmental and health issues resulting from unrecovered metals. Metal Sustainability: Global Challenges, Consequences and Prospects discusses important topics and challenges associated with sustainability in metal life cycles, from mining ore to beneficiation processes, to product manufacture, to recovery from end-of-life materials, to environmental and health concerns resulting from generated waste. The broad perspective presented highlights the global interdependence of the many stages of metal life cycles. Economic issues are emphasized and relevant environmental, health, political, industrial and societal issues are discussed. The importance of applying green chemistry principles to metal sustainability is emphasized. Topics covered include: • Recycling and sustainable utilization of precious and specialty metals • Formal and informal recycling from electronic and other high-tech wastes • Global management of electronic wastes • Metal reuse and recycling in developing countries • Effects of toxic and other metal releases on the environment and human health • Effect on bacteria of toxic metal release • Selective recovery of platinum group metals and rare earth metals • Metal sustainability from a manufacturing perspective • Economic perspectives on sustainability, mineral development, and metal life cycles • Closing the Loop – Minerals Industry Issues The aim of this book is to improve awareness of the increasingly important role metals play in our high-tech society, the need to conserve our metal supply throughout the metal life cycle, the importance of improved metal recycling, and the effects that unhindered metal loss can have on the environment and on human health.







How To Smelt Your Gold & Silver


Book Description

What's Inside? The only smelting information currently available. A complete plain English step-by-step guide for the amateur or professional. Illustrated in both color and B&W. Includes flux formulas for gold, Silver and alloys of both. Information on smelting precipitates, placer gold, scrap, concentrate, amalgam, and carbon ash. This book has a complete glossary, a supplier's index, conversion tables, equipment sources, information on what can or can't be smelted, and a comprehensive chapter on safety. Hints on how to sell your gold for more money, security, record keeping, dealing with the IRS, and more. Very easy to use and understand. Price includes technical support by the author.




Gold Refining for the Amateur Chemist


Book Description

This is a book designed for the home chemist. Are you tired of big refineries taking half of your metals? Then the processes described in this book are for you. You will learn detailed ways to recover and refine your own precious metals at home.




Rare Metal Technology 2017


Book Description

This collection presents papers from a symposium on extraction of rare metals as well as rare extraction processing techniques used in metal production. Topics include the extraction and processing of elements like antimony, arsenic, gold, indium, palladium, platinum, rare earth metals including yttrium and neodymium, titanium, tungsten, and vanadium. Rare processing techniques are covered, including direct extraction processes for rare-earth recovery, biosorption of precious metals, fluorination behavior of uranium and zirconium mixture of fuel debris treatment, and recovery of valuable components of commodity metals such as zinc, nickel, and metals from slag.