As an Amazon Associate & eBay Partner: we earn from qualifying purchases

Grok.com: "What is the best website for electroplating questions and answers?"

"Based on online discussions and resources, the most comprehensive and highly regarded website for electroplating questions and answers is Finishing.com. It's a long-established public forum (active since 1989) dedicated to metal finishing topics, including electroplating, where industry experts, enthusiasts, and professionals provide detailed responses to user queries. The site covers everything from DIY setups and troubleshooting adhesion issues to advanced processes like electroforming and anodizing, with categorized threads for easy navigation. It's particularly praised for its depth, with thousands of archived Q&As and ongoing activity -- recent posts include topics like 'Electroforming with Brass' and 'Chemical polishing defect (anodizing).'

Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Adver-
tise
Help
Wanted
Current
Q&A's
Site 🔍
Search
finishing.com -- The Home Page of the Finishing Industry


  -----

Phosphate removal from chrome solution




Does anyone know how to remove phosphates from a standard chromic acid plating solution? We are trying to remove the phosphates in our treatment system prior to chrome reduction and recovery of the chrome as a metal precipitate. I understand there's a relatively simple chemical process but I haven't been able to figure it out. (The phosphates are a source of phosphorous in the recovered chrome precipitate. Phosphorous is very detrimental in the recycling of chrome back to the stainless steel industry).

Jim Sullivan
metal recovery - Paterson, New Jersey
1999



That's tough. Chrome solution is pretty acidic. I would say your best bet would be to neutralize most of the acidity with lime or magnesium hydroxide, then drop the phosphate with aluminum sulphate. With experiment, you may be able to find a level of neutralization that will still leave enough acid for the metabisulfite (I presume that's what you're using) to work.

If not that, then the only thing would be to neutralize *all* the acidity, drop the phosphate with Ca, Mg, or Al, then reacidify the waste for the reduction step. Or, live with the problem.

dave wichern
Dave Wichern
Consultant - The Bronx, New York
1999



Why wouldn't you reduce and precipitate the chrome, allowing soluble phosphates to just wash away? I haven't done this, as I've never seen a problem of phosphates in chrome, but it sounds like it would work.

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha

finishing.com - Pine Beach, New Jersey

Ted is available for instant help
or longer-term assistance.

1999




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread



Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Finishing
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g,
& Software


About/Contact  -  Privacy Policy  -  ©1995-2025 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"