Sodium hydrogensulfite

Additional physico-chemical information

Administrative data

Endpoint:

other: corrosion test ST/SG/AC.10/11REV.4 METHOD

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: ST/SG/AC.10/11REV.4 METHOD

Deviations:

yes

Remarks:

,smaler volume of the reacting agent was used.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium hydrogensulphite

EC Number:

233-469-7

EC Name:

Ammonium hydrogensulphite

Cas Number:

10192-30-0

Molecular formula:

NH4HSO3

IUPAC Name:

Ammonium hydrogensulfite

Test material form:

other: solution

Details on test material:

- Name: Ammonium bisulfite solution
- Appearance: yellow solution

Results and discussion

Results:

During the corrosion test on aluminium, the ammonium bisulfite solution sample showed signs of moderate corrosion. The maximum weight loss was equal to 0.6 % and was found in the test-piece located in the gaseous phase of testing system A.
The value recorded is lower than the limit in the method, which is equal to 13.5 %.

Any other information on results incl. tables

EXPRESSION OF RESULTS

 

Test results were expressed in terms of weight loss percentage in the test pieces as compared with initial weight.

Weight variation % = - (initial weight - final weight) / initial weight x 100

 

RESULTS

The following table describes the results yielded by the two tests conducted in parallel on the same heating plate, but using independent systems containing two amounts of the sample referred to as A and B:

 

	Sample	Initial Weight (g)	Final Weight (g)	Weight variation %
1	Head space (A)	4.8842	4.8541	-0.616
2	Half-immersed (A)	4.9156	4.9182	0.053
3	Fully-immersed (A)	4.6620	4.6630	0.021
4	Head space (B)	4.6648	4.6416	-0.497
5	Half-immersed (B)	4.6344	4.6377	0.071
6	Fully-immersed (B)	5.4446	5.4472	0.048
7	Check in the air	4.7252	4.7251	-0.002

 

The test pieces extracted at test end were covered in a saline coat in the parts that were exposed to the gaseous phase, while the immersed portions were not coated.

The test pieces were washed in deionised water and dried using blotting paper. No significant signs of localised or overall corrosion were detected.

Prior to starting the test, the pH value of the ammonium bisulfite solution was 4.80 (at 24 °C).

At test end, the pH value of the ammonium bisulfite solutions were 4.15 in solution A and 4.20 in solution B (both taken at 25 °C), respectively.

 

The ammonium bisulfite solution concentrations before and after the test were as follows:

 

68.5 % ammonium bisulfite	(44.3 % SO2)	in the initial solution
67.5 % ammonium bisulfite	(43.6 % SO2)	in solution A at test end
65.9 % ammonium bisulfite	(42.6 % SO2)	in solution B at test end

 

Applicant's summary and conclusion

Conclusions:

During the corrosion test on aluminium, the ammonium bisulfite solution sample showed signs of moderate corrosion. The maximum weight loss was equal to 0.6 %. The value recorded is lower than the limit in the method, which is equal to 13.5 %.