Recycling of metals

F. Veys, Proceedings of the Second International Conference on the Recycling of Metals, Amsterdam, the Netherlands, Oct. 19—21, 1994, ASM International, Materials Park, Ohio, pp. 31—42. 

The initial step in the recycle of metals is the physical segregation of the metals from other materials. Eor new scrap this process is straightforward for old scrap it can be expensive. This classification and segregation of scrap is of importance to the producers of the metals from secondary materials. Historically, much of the classification has rehed on hand sorting which can be rehable, but it is labor intensive. The recycling of automotive scrap is illustrative of the... 

This shift in emphasis by the mining iadustry has led to the development and use of a variety of improved techniques, in particular the commercial avadabihty of several metal specific extractants. These techniques are particularly useful in the separations and recycling of metals from metal sludges and metal salt solutions. 

Some recycling of metals occurs much more is possible, and substitution of materials requiring less energy for those requiring more has much potential. 

A Management, Minimization, and Recycling of Metal Casting Wastes... 

Recently, the electrochemical recycKng of allyltin reagents has been realized for the first time in protic solvents. Difhculties in the recycling of metallic allyl reagents in situ are due to the fact that reaction conditions that allow... 

Production, Import/Export, Use, and Release and Disposal. Information on the production, import, export, and use of nickel metal and nickel alloys is readily available (Chamberlain 1985 Kirk 1988a, 1988b NTD 1996 Tien and Howson 1981). However, information on the production, import, and use patterns of other nickel compounds is not generally available and is needed to assess human exposure to these compounds. Except for recycling of metal scrap, little information is available regarding the disposal of nickel and its compounds. 

Enantioselective hydrogenation in ILs is of particular interest as it could provide a means for facile recycling of metal complexes of expensive chiral ligands. In their original study, Chauvin et al reported that [Rh (cod)(2)-(diop)][Pp6] catalyzed the enantioselective hydrogenation of oc-acetamidocinnamic acid to ( S)-phenylalanine with 64% ee, in a biphasic... 

Rosenbaum, S.W. September 1989. "Hydrometallurgical Recycling of Metal Sludge."... 

Use of ck clrieil counted at Kl.ftlK) Bui/kWti t liru — 11,252 kiloBfitm-c.iInne or IU55 joules Stum t "Kncru) F spendiiuros Associated uuh rhv Production and Recycle of Metals. ... 

Another aspect of concern is the limit of resources in the world. Some decades ago, the term recycling was almost unknown. At the present time recycling is a household term and recycling of metal products, paper and plastics has been recognized for the important role it plays in conserving our resources. We have reached a level of maturity to be able to recognize that our natural resources are limited and finite in our world, and that methods to conserve these resources by recycling and other methods have a prominent role to play. 

Fig. 2. 23 During early degradation Ej (L) of the leaf titter is kept close to -0.15V allowing for unfractionated recycling of metal ions which got thereby back to the soil interface. Rather than modifying functional groups, C/O (carbohydrate) or C/N (protein) or C/C (polyphenol) backbones extended lines) are cleaved by hydrolysis or oxidation products with broken lines) while the functional groups squares linked to the line(-parts) perpendicularly) remain active towards metal ions round dots)...

In this case, pst is proportional to the mass-transport coefficient km, which can be increased by forced convection, for example, through agitation of the solution, enhanced electrolyte flow, turbulence promoters, or setting the electrodes in motion. Equations (12) and (14) are the key formula for the optimization of electrochemical cell design. Equation (14) is of particular importance for reactions with low concentrations, for example, recycling of metals from spent solutions or wastewater. 

W. Pietsch, Agglomeration. Key to the recycling of metal bearing fines , in Proceedings of International Symposium on Recycle and Secondary Recovery of Metals, Fort Lauderdale, Fla., USA, The Metallurgical Society of AIME, 1985, pp.683-99. 

Metal items constitute an appreciable amount of solid waste, with their percentage varying between 5 and 15 percent in most cases. As the revenue from solid-waste processing plants is derived from the sale of the separated products, among which ferrous and nonferrous metal items, the recovery and recycling of metallic objects support considerably the construction and operation of solid-waste treatment plants. The recycling of metal items is very important, as it contributes in mineral deposits conservation and in the prevention of environmental pollution from the oxidation and dissolution of various metals, being in alloyed form. 

G. Martin, A. Siegmund, Recycling of Metals and Engineering Materials, The Minerals, Metals and Materials Society, 2000, pp. 93-101. 

R. Leiby, M. Bricker, Proc. 1995 International Symposium on Recycling of Metals and Engineered Materials Recycling Symposium, Point Clear, AL, USA, 1995. 

W. Pietsch, Briquetting of non-ferrous waste for economic recycle. Proc. 2nd IntT Symposium Recycling of metals and engineered materials (J.H.L. van Linden, D.L. Stewart, Y. Sahai, eds.), TMS, Warrendale, PA (1990), 667-670. 

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