Plating with Trivalent Chrome
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چکیده
Hexavalent chromium wastes need to be chemically reduced to trivalent chrome in the shop’s treatment plant. This necessitates the use of expensive chemicals such as sulfur dioxide, sodium metabisulfite or sodium borohydride. Also considerable hazardous sludge is generated during the neutralization step of the treatment process due to the high chromium concentration of the plating solutions. Hazardous waste haulage and disposal.costs are rising dramatically each year. Thus, it’s becoming harder to use hexavalent systems profitably.
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