Reaction mass of potassium sodium (2R,3R)-2-hydroxy-3-(phosphonatooxy)butanedioate and potassium sodium (2S,3S)-2-hydroxy-3-(phosphonatooxy)butanedioate

Additional physico-chemical information

Administrative data

Endpoint:

other: corrosive to metals

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13-20 Oct 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: UN Method C.1

Deviations:

yes

Principles of method if other than guideline:

Metal sheet (steel and aluminium coupons) immersion test at 55 °C for 1 week.
Deviations:
- At least 3 sets (9 spicemens) of each material shall be used (UN/SCETDG/20/INF.27)
- The entrance of air has to be guaranteed (UN C.1). Not achieved in closed bottles used.
- For hygroscopic substances the UN Subcommitee of Experts ofTDG recommends: “… in case, the most aggressive concentration is not known by the tester, he has to approach the concentration with the highest corrosiveness in steps of 10%. Therefore two or three tests have to be carried out at the same time". (UN/SCETDG/20/INF.27)

GLP compliance:

no

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): reaction mass of tetra (potassium and sodium) (2R, 3R)-2-hydroxy-3-(phosphonatooxy) succinate and tetra (potassium and sodium) (2S,3S)-2-hydroxy-3-(phosphonatooxy) succinate
- Appearance: white granular powder
- Analytical purity: >=84% (w/w)
- Date of production: 16 Sep 2014
- Lot/batch No.: 010-2065

Results and discussion

Results:

Concentrated aqueous solutions of the test substance can be considered as not corrosive to metals.

Any other information on results incl. tables

There was no visual damage to the coupons employed (see attached figure). No signs of localized corrosion could be detected.

Detailed results:

Specimen	Steel C1010	Aluminium AL1100H14
Test duration in days (d)	7	7
Metal sheet factor (f)	0.025	0.074
Starting weight (g)	8.2014	3.0052
Weight after test (g)	8.1990	3.0041
Mass loss (g)	0.0024	0.0011
Corrossion rate (mm/a)	0.01	0.00

The corrosion rates determined (0.01 mm/a for steel and 0.00 mm/a for aluminium) do not exceed the threshold value of 6.25 mm/a for any of the two metals tested.