Nickel Insitute - Nickel Alloys in Organic Acids & Related Compounds

TABLE XXXIV

Corrosion of Five Alloys in Boiling Aqueous Formic Acid Solutions

Test Conditions: Average rate of duplicate specimens ex- posed in boiling 100-107 ºC (212-223 ºF) solutions for 96 hours except as noted. No aeration or deaeration.

Corrosion Rate

Type 304 Stainless Steel

Type 316 Stainless Steel

C70600 (90-10 Cupro-Nickel)

Test A

Test B*

Test A

Test B*

Copper

Titanium

Formic Acid

mm/y mpy mm/y mpy mm/y mpy mm/y mpy mm/y mpy mm/y mpy mm/y mpy

1 5

.18 .79

7

.36

14 42 60 69 94 83 83 91 84 83

.08 .05

3 2

<.03 < 1 .20 8 .20 8 .20 8 .25 10 .28 11 .23 9 .25 10 .25 10 .28 11

.03 .03 .03 .20 .12 .25 .05 .76 .20 .23

1 1 1 8 5

.03

1 1 1

– –

– –

31 53 76

1.07 1.52 1.75 2.39 2.11 2.11 2.31 2.13 2.11

03

10 20 40 50 60 70 80 90

1.34 1.93 3.45

25

10 11

.03

13

5

.28 .10

41

16 13 21

2.41

95

136 4.24** 167** 3.45** 136** 4.04** 159** 4.29** 169** 3.28** 129**

4

.33 .53 .03 .71

– – 3.05 120 – – – – – – <.03 <1

.51** .46** .48** .48** .28**

20** 18** 19** 19** 11**

10

2

1

30

28

8 9

13

5 7

.18

*Test solution changed each 24 hours of the 96-hour test. **Test discontinued after 48 hours because of concentration of corrosion salts in solution.

TABLE XXXV

Corrosion of Alloys in Boiling Formic Acid Solutions

Test Conditions: Laboratory test results averaged from three separate 48-hour test periods in most cases. Tests conducted with and without aeration in acid concentrations noted.

Corrosion Rate

10%

50%

90%

99%

Unaerated*

Unaerated*

Aerated

Unaerated*

Aerated

Unaerated

Liquid

Vapor

Liquid

Vapor

Liquid

Vapor

Liquid

Vapor

Liquid

Vapor

Liquid

Vapor

Alloy

mm/y mpy mm/y mpy

mm/y mpy mm/y mpy mm/y mpy mm/y mpy

mm/y mpy mm/y mpy mm/y mpy mm/y mpy

mm/y mpy mm/y mpy

Mild steel

–

–

–

–

–

–

–

–

–

–

–

–

24.13 950

–

–

–

–

–

–

–

–

–

–

Type 430

–

–

–

–

–

–

–

–

–

–

–

–

11.26 444

.89

35

–

–

–

–

–

–

–

–

stainless steel Type 304 stainless steel Type 310 stainless steel Type 316 stainless steel Type 317 stainless steel CARPENTER alloy 20 HASTELLOY alloy C HASTELLOY

–

–

–

–

–

–

–

–

–

–

–

–

10.41 410

1.52

60

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

10.21 402

.61

24

–

–

–

–

–

–

–

–

.18

7

.23

9

.23

9

.53

21

<.03 <1

74

29

.36

14

.18

7

< 03 < 1

.79

31

.13

5

.10

4

–

–

–

–

–

–

–

–

–

–

–

–

.13

5

.13

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

<.03 <1

30

12

.05

2

–

–

03

<1

.66

26

–

–

–

–

–

–

–

–

–

–

–

–

.10

4

03

1

.05

2

–

–

10

4

<.03 <1

–

–

–

–

–

–

–

–

–

–

–

–

.51

20

10

4

.08

3

–

–

08

3

.03

1

–

–

–

–

alloy B INCONEL alloy 600 MONEL alloy 400 Nickel 200

–

–

–

–

–

–

–

–

–

–

–

–

.76

30

.64

25

1.24 45

.20

8

–

–

–

–

<.03 <.1

.08

3

.23

9

.08

3

–

–

–

–

.03

1

.03

1

7.62 300

.23

9

–

–

–

–

.15

6

.15

6

.36

14

.43

17

.84

33

2.24

88

.61

24

.28

11

69 27 14.30 563

.41 16 37.80 93

–

–

–

–

Copper

.08

3

.18

7

.13

5

.28

11

–

–

–

–

.25

10

.15

6

–

–

–

–

EVERDUR 1010

–

–

–

–

–

–

–

–

–

–

–

–

.18

7

.23

9

3.30 130

.69

27

–

–

–

–

Aluminum 3003 31.09

1224

21.89 862

–

–

–

–

31.70 1248

10.16 400

7.62 300

–

–

10

4

<.03 <1

–

–

–

–

Titanium

.13

5

–

–

2.92 115

–

–

–

–

–

–

<.03 <1

–

–

–

–

–

–

–

–

–

–

Chromium

.51

20

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

–

carbide with 12% nickel binder

*Boiling solution without sparging of any gas.

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