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Where did the cyanide go?

I RUN A SILVER ELECTROPLATER.IT IS NEW.EVERYTHING WAS GOING WELL UNTIL TODAY.THURSDAY I ADDED THE FIRST CYANIDE ADD SINCE I FIRST MADE THE BATH(32 HOURS OF RUN TIME ON BATH).IT TESTED AT 8.2 11 IS OPTIMAL THE BATH ALSO TESTED LOW FOR SILVER SO I REPLENISHED ALL 105 LBS I'D USED AND ADDED 3 MORE BASKETS HALF FULL OF ANODES.MY CALCULATIONS SHOWED 50 LBS OF CYANIDED WAS NEEDED.TODAY 24 HRS AFTER THE ADD THE PLATING THICKNESS DROPPED TO A TENTH WHAT IT SHOULD BE.I CHECKED EVERYTHING.VOLTS AND AMPS ARE STABIL.ALL MECHANICS ARE WORKING.I CLEAN WITH SODIUM HYDOXIDE,ALL WAS WELL THERE TO.SO WITH NOTHING LEFT TO CHECK BUT THE BATH,I DID.IT TESTED AT 7.6 AND VERY LOW FOR SILVER(YES ALL THE SILVER IS STILL IN THE BASKETS)WHERE DID THE CYANIDE GO?THE BATH IS UNHEATED AND THE PROCESS USES A STRIKE BEFORE FINAL PLATING,ALL NUMBERS WERE OPTIMAL THERE.ALL THE WIERD QUIRKS I'VE WORKED OUT OF THIS MACHINE WERE "FUN" BUT NOW I'M LOST.CAN SOMEONE PLEASE POINT ME IN THE RIGHT DIRECTION?

DONALD HITMAN
I RUN A SILVER ELECTROPLATER - Lisbon, New Hampshire, USA
November 5, 2010

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Hi, Donald. Lose the all-caps please! Between them and no spaces for punctuation, I literally can't read your posting, and hope others can, and will help you. Did you plate successfully between the cyanide add and the next morning? Any possibility that you added 50 pounds of caustic flake instead of cyanide? Any heavy sludge at the bottom of the tank?

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
November 10, 2010

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High cyanide will really slow down the plating rate! There is an optimum of each, silver, cyanide and caustic to get a good plate rate and not cause other problems. A little off makes a huge difference for good plate.
I question your analysis. Bring in a plating chemist or tech services from the company that you bought the plating solution from. If it is a home brew, definitely bring in a superior plating chemist for a consult.

James Watts
- Navarre, Florida
November 11, 2010