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Abstract

A blended, apparently new, non-chromate corrosion inhibitor for cooling water systems using tap or brackish water has been developed from sodium hexametaphosphate, phosphoric acid, and sodium nitrite (in the ratio 10: 4: 1). The performance of this inhibitor in protecting carbon steel was evaluated, in simulated environments typical of local conditions in Kuwait, using electrochemical polarisation and corrosion rate measurements. Tests were conducted in circulating rigs operated at a water velocity of 1·71 m s⁻¹, a temperature of 40 ±1°C, and apH of 7·8–8·0. The nature of the corrosion product formed on the carbon steel was studied by optical microscopy, SEM, and EDS. Linear polarisation resistance corrosion rate measurements indicate that the efficiency of the blended mixture exceeds 95%. The inhibitive effect arises from formation of a coherent protective film which may contain calcium phosphate.

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References

Hatch

G. B.

and Rice

: Ind. Eng. Chem., 1939, 31, 51.

Hatch

G. B.

and Rice

: Ind. Eng. Chem., 1940, 32, 1572.

Rice

: J. Am. Water Works Assoc., 1942, 34, 1954.

Raistrick

: Chem. Ind., 1952, 408.

Uhlig

H. H.

, Triados

D. N.

, and RI. STERN: J. Electrochem. Soc., 1955, 102, 59.

Akiyamma

and Saji

: J. Electrochem. Soc. Jpn, 1971, 39, 210.

Nichols

J. D.

, Clavin

J. S.

, and BLASDEL

J. E.

: Hydrogen Proc., 1980, 59, 75.

May

B. C.

, Geiger

G. E.

, and BAUER

D. A.

: Mater. Perform., 1981, 20, 34.

Mayne

J. E. O.

and Pryor

M. J.

: J. Chem. Soc., 1949, 1831.

10.

Brasher

D. M.

, Kingsbury

A. H.

, and MERCER

A. D.

: Nature, 1951, 180, 27.

11.

Brasher

D. M.

, Beynon

J. G.

, RAJAGOPALAN

K. S.

, and THOMAS

J. G. N.

: Br. Corros. J., 1970, 5, 264.

12.

Lumsden

J. B.

and Szklarska-Smialowska

: Corrosion, 1978, 34, 169.

13.

Kahler

H. L.

: US Patent 2, 711,391, 1955.

14.

Kelly

T. E.

, Kise

M. A.

, and STEKETrEE

F. B.

: Mater. Prot. Perform., 1973, 12, 28.

15.

EL-HOSARY

A. A.

and Gawish

M. M.

: Egypt. J. Chem., 1981, 23, 67.

16.

Islam

, AL-MAZEEDI

, and Abdullah

: Proc. 8th Int. Cong. on Metallic Corrosion, Mainz, September 1981, 1233; 1981, Frankfurt am Main, Dechema.

17.

Butler

: Proc. 3rd European Symp. on Corrosion Inhibitors, Ferrara, 1970, 753; 1971, Ferrara, University of Ferrara.

18.

Winters

M. A.

: Ind. Corros., 1987, 5, (6), 13.

19.

Qian

Y. J.

and Turgoose

: Br. Corros. J., 1987, 22, 268.

20.

Rozenfeld

I. L.

: ‘Corrosion inhibitors’, 176; 1981, New York, McGraw-Hill.

21.

Poulson

: Corros. Sci., 1983, 23, 391.

22.

Roseenberg

A. M.

, Caidis

J. M.

, KOSSIVAS

T. G.

, and PREVITE

B. W.

: in ‘Chloride corrosion of steel in concrete’, STP 629, 89; 1977, Philadelphia, PA, ASTM.

23.

Pryor

M. J.

and Cohen

M. J.

: J. Electrochem. Soc., 1953, 100, 202.

Non-chromate corrosion inhibitor for cooling water systems

Abstract

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