topic 26547
M-nitrobenzene sulphonic acid sodium salt for stripping nickel
2004
Q. Is the product you are talking about as m-nitrobenzene sulphonic acid (nickel stripper -- see topic 11992), the same as our product m-nitrobenzene sulphonic acid sodium salt? I have a plant produce m-nitrobenzene sulphonic acid sodium salt. Please let me know if it is the same product as my english is poor.
Thks and Regards,
ALACE HANmanager - DEZHOU, SHANDONG, CHINA
2004
A. The two differ; the salt is precipitated by adding NaCl to the acid solution in water. Also, note that sulphonic is often spelled sulfonic, and nitrobenzenesulfonic may be written as a single word.
m-nitrobenzene sulphonic acid
Formula: C6H5NO5S or C6H4(NO2)(SO3H)
CAS #98-47-5
Synonyms: m-nitrobenzenesulfonic acid, 3-nitrobenzenesulfonic acid.
m-nitrobenzene sulphonic acid sodium salt
Formula: C6H4NaNO5S or C6H4(NO2)(SO3Na)
CAS #127-68-4
Synonyms: m-nitrobenzenesulfonic acid sodium salt,
3-nitrobenzenesulphonic acid sodium salt, Meta-nitro Benzene Sulfonic Acid - Sodium Salt, m-Nitrobenzene sodium sulphonate.
- Goleta, California

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The mechanism of cyanide-free nickel stripping with MNBS
2004Q. Academically speaking, what is the mechanism by which nickel plating is stripped from steel using meta-nitrobenzenesulfate, ethylenediamine, and alkaline conditions?
Scott ThompsonCeramic Manufacturer - Auburn, California, USA
A. To strip you need to oxidise the metal to be dissolved and have a solvent or complexant to solubilise the cations. In the case of chemical dissolution of nickel the MNBS is the oxidant and either cyanide or the amine is the solvent. When an amine is the solvent or complexant you also need an activator which is usually a sulphur compound e.g., thiocyanate, dithiocarbamate etc. In the case of electrolytic stripping the oxidising is done by the DC voltage and the solvent ammonium nitrate or sulphuric acid.

Geoffrey Whitelaw
- Port Melbourne, Australia
July 26, 2019
Q. Hello!
Can Sodium Meta nitrobenzene sulphonic acid be used to make non cyanide nickel stripper?
Chemi International - Mumbai,India
July 2019
A. Hi Kishore. Geoff said yes in the linked thread previously referenced (topic 11992), but Ken implied that you should double-check the actual chemical formula to avoid misunderstandings. To best attract new responses, please heed our advice, which is based on posting a quarter million questions here and monitoring their response level for 24 years :-)
Luck and Regards,

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