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Recycling silver

The cost of various silver compounds is a function of the silver market price. In 1980, the estimated usage of silver ia the United States was 3730 metric tons (120 X 10 troy oz) (23). This silver is derived from silver mined within the United States silver recycled or reclaimed from secondary sources, eg, coiaage, flatware, jewelry, and photographic materials and imported silver. In 1980, Canada, Mexico, and Pern, the principal exporters of silver to the United States, shipped 1670 tons (53.8 x 10 troy oz) as silver buUion and silver compounds. U.S. imported 2799 t and exported 964 t ia 1988 (23). [Pg.91]

Construction Waste oA Demolition Debris Recycling—A Primer, PubHcation. No. GR-REC 300, The SoHd Waste Association of North America, Silver Spring, Md., Oct. 1993. [Pg.557]

New silver accounts for only a portion of the silver used ia the United States. Recycled silver makes up the difference. AvailabiUty of recycled silver depends on market price. As the market price iacreases, so does the flow of recycled silver (see Recycling, nonferrous metals). The New York price reached an all-time high of 1543/kg ( 48.00/troy oz) onjanuary 21, 1980, primarily as a result of speculation. The price fell to 347.30/kg ( 10.80/troy oz) four months later as the pressure of speculative activity ia the silver market lessened. Comprehensive reviews of the silver market are published yearly the New York prices between 1985 and 1988 were as follows (23). [Pg.91]

Catalyst lifetime for contemporary ethylene oxide catalysts is 1—2 years, depending on the severity of service, ie, ethylene oxide production rate and absence of feed poisons, primarily sulfur compounds. A large percentage (>95%) of the silver in spent catalysts can be recovered and recycled the other components are usually discarded because of thek low values. [Pg.202]

In the case of phenylchlorosilanes some modifications are made to the process. Chlorobenzene is passed through the reaction tube, which contains a mixture of powdered silicon and silver (10% Ag), the latter as catalyst. Reaction temperatures of 375-425°C are significantly higher than for the chloro-methylsilanes. An excess of chlorobenzene is used which sweeps out the high boiling chlorophenysilanes, of which the dichlorosilanes are predominant. The unused chlorobenzene is fractionated and recycled. [Pg.819]

Silver, Ag, is rarely found as the metal. Most is obtained as a by-product of the refining of copper and lead, and a considerable amount is recycled through the photographic industry. Silver has a positive standard potential, and so it does not... [Pg.786]

A different concept is the idea of manufacturing at point of use rather than transporting materials. A simple and familiar example is the office water cooler. The majority that you see around use large bottles of water. These need to be transported and stored and the empty bottles recycled. More than 600 kT of bottled water were imported into the UK in 1999, creating a significant transport impact. The alternative is to chill and filter mains water on-site. The water needs to be filtered and purified to meet consumer perceptions and expectations. These systems use a mixture of purification techniques including advanced filters, UV-disinfection and silver-treated surfaces to give users the confidence they require. [Pg.54]

As mentioned above, approximately 7% of the total sulfur present in lead ore is emitted as S02. The remainder is captured by the blast furnace slag. The blast furnace slag is composed primarily of iron and silicon oxides, as well as aluminum and calcium oxides. Other metals may also be present in smaller amounts, including antimony, arsenic, beryllium, cadmium, chromium, cobalt, copper, lead, manganese, mercury, molybdenum, silver, and zinc. This blast furnace slag is either recycled back into the process or disposed of in piles on site. About 50 to 60% of the recovery furnace output is slag and residual lead, which are both returned to the blast furnace. The remainder of this dross furnace output is sold to copper smelters for recovery of the copper and other precious metals. [Pg.90]

Precious metals reclamation Precious metals reclamation is the recycling and recovery of precious metals (i.e., gold, silver, platinum, palladium, iridium, osmium, rhodium, and ruthenium) from hazardous waste. Because U.S. EPA found that these materials will be handled protectively as valuable commodities with significant economic value, generators, transporters, and storers of such recyclable materials are subject to reduced requirements. [Pg.441]

Recycle waste batteries if possible. Batteries with high levels of mercury or silver can be recovered for the refining process. The mercuric oxide batteries can be targeted for recollection and... [Pg.1228]

Mercury oxide and silver oxide button batteries are sometimes collected by jewelers, pharmacies, hospitals, and electronic or hearing aid stores for shipping them to companies that reclaim mercury or silver. Some batteries cannot be recycled. If recycling is not possible, batteries should be saved for disposing of at a hazardous waste collection. Battery recycling and button battery collection may be good options at present, but may change as the mercury concentration in the majority of button batteries continues to decrease. [Pg.1229]

Manufacture of cell phones and personal computers consumes 3% of gold and silver mined worldwide each year, and 13% of palladium and 15% of cobalt as well. Electronics contain approximately 60 elements, some valuable and hazardous, or both [13], Recycling the valuable elements is the driving force behind the intensive activities engaged in disposal of e-waste. [Pg.281]

Silver chloride separation and economic recovery of silver for recycling back to the process. [Pg.26]

Based on the test runs, AEA concluded that catholyte-to-anolyte recycle and periodic removal of an anolyte purge stream (to simulate IRS operation) controlled the anolyte acid concentration, as well as the catholyte silver and organics concentrations. The catholyte silver ion concentration was held at the target 1 M level proposed for the full-scale system. [Pg.69]

A continuous recycle stream from the catholyte to the anolyte circuit in the main process system has been added. This recycle stream is needed to maintain concentrations of silver, organic material, dissolved metals, and other acids at acceptably low levels in the catholyte. [Pg.79]

The realistic potential foroff-site recycling/reuse of silver salts and concentrated nitric acid must be evaluated, including recyclers ability to accept, handle, and treat these materials. [Pg.90]

Compressed oxygen, and fresh and recycled ethylene, are heated, mixed, and then passed through a reactor with fixed beds of catalyst— silver oxide deposited on alumina pellets. In recent years the catalyst has been improved by the addition of promoters and inhibitors. (Promoters—in this case compounds of alkali or alkaline rare earth metals—enhance the activity of the catalyst inhibitors—in this case chlorine compounds—chloroethane, or vinyl chloride, reduce its rate of activity decline.)... [Pg.148]


See other pages where Recycling silver is mentioned: [Pg.90]    [Pg.86]    [Pg.90]    [Pg.86]    [Pg.493]    [Pg.494]    [Pg.494]    [Pg.379]    [Pg.304]    [Pg.47]    [Pg.139]    [Pg.458]    [Pg.459]    [Pg.509]    [Pg.80]    [Pg.455]    [Pg.42]    [Pg.256]    [Pg.490]    [Pg.274]    [Pg.1713]    [Pg.40]    [Pg.383]    [Pg.400]    [Pg.500]    [Pg.514]    [Pg.515]    [Pg.541]    [Pg.823]    [Pg.844]    [Pg.305]    [Pg.59]    [Pg.79]    [Pg.79]   
See also in sourсe #XX -- [ Pg.690 ]

See also in sourсe #XX -- [ Pg.747 ]

See also in sourсe #XX -- [ Pg.36 ]

See also in sourсe #XX -- [ Pg.781 ]




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