Non-chromated De-oxidizer
Non-chromated De-oxidizer
(OP)
Non-chromated De-oxidizer
Our company uses an in-house mixed Non-chromated De-oxidizer. The percentages are fairly simple but duplicating the formula for the initial charge is posing a problem. The person who created the mix in the first place has retired and left for places unknown.
It is:
H2SO4 5-10%
HNO3 5-10%
FeSO4 15-25%
The trick is to match the total acid to the total ferrous at around 10%-20% any one have an idea on the quantities required to make up a 2000 gallon bath?
Our company uses an in-house mixed Non-chromated De-oxidizer. The percentages are fairly simple but duplicating the formula for the initial charge is posing a problem. The person who created the mix in the first place has retired and left for places unknown.
It is:
H2SO4 5-10%
HNO3 5-10%
FeSO4 15-25%
The trick is to match the total acid to the total ferrous at around 10%-20% any one have an idea on the quantities required to make up a 2000 gallon bath?





RE: Non-chromated De-oxidizer
RE: Non-chromated De-oxidizer
RE: Non-chromated De-oxidizer
RE: Non-chromated De-oxidizer
RE: Non-chromated De-oxidizer
Grading/corrections will be appreciated.
RE: Non-chromated De-oxidizer
The more expensive deoxidizer (Oakite LNC) differs in not using (cheap) sulfuric acid but rather an acid salt (POTASSIUM PEROXYMONOSULFATE), and it also includes some HF (helps with Si-containing alloys).
The ferric sulfate's role is to prevent etching of the aluminum after the acids have removed any oxide or smut (hydroxides formed from caustic etching). It forms a very thin immersion plating of Fe via an exchange reaction with the exposed Al (since Fe is more noble). This trace of Fe contaminates the subsequent chemfilm layer, so for best corrosion resistance (& passing the salt spray test requirements) it is better to use a non-Fe-containing deox.
For some Al alloys, one can simply use 20 vol% nitric acid to desmut.