Claims
- 1. A method for protecting metallic surfaces which are in contact with a corrosive aqueous energic or thermic fluid and tend to be corroded thereby which comprises incorporating in said fluid between 3 and 500 ppm by weight of a fluorophosphate compound corrosive inhibitor selected from the group consisting of:
- (i) compound of the formula M.sub.2.sup.I PO.sub.3 F, xH.sub.2 O
- (ii) compound of the formula LiM.sup.I PO.sub.3 F, xH.sub.2 O
- (iii) compound of the formula NaM.sup.I PO.sub.3 F, xH.sub.2 O
- (iv) compound of the formula M.sup.II PO.sub.3 F, xH.sub.2 O
- (v) compound of the formula M.sub.2.sup.I M.sup.II (PO.sub.3 F).sub.2, xH.sub.2 O
- (vi) compound of the formula M.sup.I PO.sub.2 F.sub.2, xH.sub.2 O
- (vii) compound of the formula M.sup.II (PO.sub.2 F.sub.2).sub.2, xH.sub.2 O and
- (viii) mixtures thereof ;wherein M.sup.I is Na, K, Rb, Cs or HN.sub.4 ; M.sup.II is Mg, Ca, Ba, Sr, Zn, Cd, Mn, Ni or Co; and x is an integer or a fractional number comprised between 0 and 6.
- 2. A method according to claim 1 in which the corrosion inhibitor is zinc fluorophosphate.
- 3. A method according to claim 1 in which the corrosion inhibitor is potassium fluorophosphate.
- 4. A method according to claim 1 in which said corrosive fluid also contains a substance (B) selected from the group consisting of polyamines, organic polyelectrolytes resulting from polymerization and copolymeriation of a monomer having a C.dbd.C double bond, alkylenephosphonic acid derivatives, aminoalkylene phosphonic acid derivatives and mixtures thereof.
- 5. A method according to claim 4 in which there is from 1-100 parts dry weight of substance (B) per from 1-15 parts dry weight of fluorophosphate.
- 6. A method according to claim 1 in which the corrosive fluid contains zinc fluorophosphate in an amount between 5 and 200 ppm by weight.
Priority Claims (1)
Number |
Date |
Country |
Kind |
82 09426 |
May 1982 |
FRX |
|
Parent Case Info
This application is a continuation of application Ser. No. 497,572 filed May 24, 1983, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4132572 |
Parant et al. |
Jan 1979 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
0010485 |
Apr 1980 |
FRX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
497572 |
May 1983 |
|