| 摘要 |
Silver from used manufactured organic materials such as photographic film, sensitized paper and printed circuit boards, is recovered by placing the material in an enclosed retort and subjecting the retort to a noncombustible atmosphere such as steam and then increasing the temperature of the material to a final temperature between 500 DEG and 960 DEG C. to vaporize the volatile constituents and carbonize the organic material to leave a silver and carbon residue. The silver is then separated from the carbon by burning the carbon in a combustible atmosphere to transform the residue into silver and ash. The silver and resulting ash may be efficiently separated by conventional flux or flotation processes.
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