Non-Cyanide Plating Solutions

While attractive from a cost and liability standpoint when waste disposal is included, this substitution is still thwarted by technical challenges. These are summarized for non-cyanide zinc plating in the following table, along with benefits, projected and realized. 

Zinc chloride 97-100% efficiency (higher production rates) (lower energy costs) bright finish accept most chromaters low cost chemistry Reduced ductility over. 5 mil thickness reduced plate distribution high capital cost for equipment (corrosion resistance) tighter chemical control required 

Alkaline zinc Good throwing power no special equipment required lower waste treatment costs Reduced ductility over. 5 mil thickness does not plate well over cast iron and heat-treated steel tighter chemical control required 

It may be possible to improve the operation of zinc cyanide process solutions and effect enormous reductions in waste generation.[12][13] After improving operations, it may be further possible to capture and return escaped process solution from the rinsing system. However, even if cyanide plating systems could be close-looped and the process solutions successfully maintained using standard purification techniques, the trend is definitely towards the substitutes. It may be necessary to operate 

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