Surplus plating solutions: shelf-life? repurposing? trading?

A. Hi Allan. Companies like Cemco ⇩ (So. Plainfield, NJ) or Inmetco ⇩ (Ellwood City, PA) may be able to take your solutions for recycling at an acceptable cost or possibly for free or token payment.

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

Ed. update 2026: These firms no longer seem to be in business.

A. Your answers are:
1) 1 Faraday will deposit 1 gram equiv. wt of metal, assuming 100% efficiency. Unfortunately not all metals are deposited with 100% efficiency. 1 Faraday is equivalent to about 96,485 Coulombs.
2) The electrolyte will be good for as long as you can keep it without getting contaminated or it evaporating away. You may want to keep it in a well sealed container to prevent any contamination by dust, debris or gases.

A. You are geographically not very far from a nickel refinery. You might ask them whether they want the materials.

A. Hi Randy. You can get an MSDS from Technic so you know what you are dealing with. Have you asked them whether they will take it back? Assuming that this is unused plating solution, it's not a hazardous waste because it's not waste. But it is hazardous, and transportation is probably governed by DOT.

If Technic won't take it, find a local plating shop (see our Shops Directory or your yellow pages) to take it. Don't expect much money for it (they'll be saving you a fortune) but make sure to do a bill of sale and make sure they pay you at least a dollar rather than vice versa, to document the fact that they bought saleable product and you did not dispose of waste! This is obviously just my limited knowledge, not legal advice, but plating waste products can get you deeply in trouble because the generator is responsible for them forever, no matter how much they pay for disposal.

It often strikes people as unfair that if they pay good money for disposal they are still responsible for it forever anyway, and they wonder how that could possibly be the law. The EPA has found arrangements between waste generators and fly-by-night waste haulers sometimes results in improper disposal of the waste and the hauler never located -- their solution is you remain responsible.

Good luck.

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

I have been experiencing problems of spotting continually without remedy and am incredibly frustrated with the rhodium process. I use a Rectifier tuned to 5 volts and 2.5 amps. I have used a copper, gold, and stainless dip wire. I use a platinized titanium anode supplied by Stuller 2" x 3" approx. mesh. I use the Clean Earth electrocleaner and activator. I use reverse osmosis water in all but the plating solution. I have electrocleaned from 30-60 seconds @ 150 °F I have activate for 1 minute then plated in 110 °F bath for 10-12 seconds. The result is a decent looking plate but upon closer inspection there is discolorization or spotting. Often the spotting is the worst close to the dipping wire. I just tried everything with a brand new bottle. I have purchased multiple bottles from you over the years and have been having unsatisfactory results. Unless something changes quickly I will be forced to find another supplier as the rhodium solution is the only thing I have not changed completely. I plate only rings of typically jewelry store size , solitaires, eng. ring, men's rings, etc.

A. I think your current is too high. Try about 2 volts and leave the current to find its own level. Increase time to between 30 seconds and one minute.

A. Hello,
It's a shame that all your vendor can come with is that the Rh concentrate has expired. If I provided technical service of that level even years ago, I wouldn't have had many active accounts. I've had customers in the past use the same Rh plating solutions for more than four years. This of course is due to good plating practices and good housekeeping. I agree with Neil Bell that you should decrease your voltage. There is usually 8-12 grams of Rh metal per gallon in decorative applications, so you have to be very careful with voltage. Metal concentration goes hand in hand with applied amperage. You also want to be sure you have enough Sulfuric Acid in the bath. Good Luck!

Ed. note: This thread offers Mark's experience that shelving the product up to 4 years did not cause him problems. But with its introduction of rhodium plating troubleshooting we should note that we have several threads on rhodium plating problems if readers wish to search the site.

A. Good day Wayne.

You state the solutions are still sealed.
Are they in unopened shipping containers from the supplier? Do you have tech data sheets on the proprietary solutions?
Have you done an analysis on the metal contents, and have you performed Hull Cell ⇦ huh? testing to see if indeed they perform as required?
You need to determine the value of the solutions and how they perform.
You can sell/buy a clean, shiny used car, but if the heads are blown, how far will it go?
Good luck.

Regards,