Tetrakis(hydroxymethyl)phosphonium chloride, oligomeric reaction products with urea

Storage stability and reactivity towards container material

Administrative data

Endpoint:

storage stability and reactivity towards container material

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Test Methods and Criteria Relating to Substances of Class 8, Test C.1.

Principles of method if other than guideline:

Test coupons

The metal coupons used in this study were supplied by European Corrosion Supplies Ltd, Kidderminster,
(a) Aluminium - Type 7075 – T6, 50 x 25 x 1.6mm, 5mm diameter suspension hole.
(b) Steel - Type S275J2G3, 50 x 25 x 3mm, 5mm diameter suspension hole.

The test method suggests coupon sizes of 50 x 20 x 2mm and calculates weight loss limits of 13.5, 26.5, 39.2 and 51.5% for 7, 14, 21 and 28 days exposure based on a corrosion rate of 6.25 mm/year. The coupons available were of a slightly different size so the 6.25 mm/year corrosion rate gives different weight losses for the same exposure times.

Type of method:

other:

Test material

Test material information

Constituent 1

Specific details on test material used for the study:

Approximately 1 litre of Perform CC was charged to a 2 litre jacketed glass vessel fitted with reflux condenser and heated using an external Haake oil heater/circulator. Three pre-weighed test coupons were suspended by PTFE tape such that one was fully immersed in the liquid, one half-immersed and the other suspended in the vapour space above the liquid surface. Separate tests were run for aluminium and steel coupons. The vessel was heated at 55°C (oil bath set point 56.5°C) for 7 days, after which the coupons were washed, all loose deposits removed with a plastic brush, cleaned with acetone, dried and re-weighed.

Results and discussion

Any other information on results incl. tables

Aluminium 7075-T6 (50 x 25 x 1.6mm)
Coupon	#183 Fully immersed	#182 Half immersed	#181 Vapour phase
Appearance after 7 days	Mottled dull, dark grey staining.	Immersed half as coupon #183. Prominent band of dull, dark staining at liquid/air interface. Exposed half stained where splashed with liquor.	Dark staining where splashed with liquor. Otherwise bright and shiny.
Initial weight (g)	5.5052	5.4647	5.5065
Final weight (g)	5.5042	5.4640	5.5065
Weight loss (mg)	1.0	0.7	0.0
Weight loss (%)	0.02	0.01	0.00
Corrosion rate (mil/year)	2.7	1.9	0.0
Corrosion rate (μ/year)	6.8	4.8	0.0
Corrosion rate (mm/year)	0.01	<0.01	0.00
Steel S275J2G3 (50 x 25 x 3mm)
Coupon	#10 Fully immersed	#07 Half immersed	#04 Vapour phase
Appearance after 7 days	Small amount of surface deposit. Light pitting. Dull, dark grey colouration with feint light brown rust-like stains	Immersed half as coupon #10. Exposed half showed dark brown rustlike stains where splashed with liquor.	As exposed half of coupon #07. Stains feel rough to the touch compared to unstained
Initial weight (g)	28.5308	28.4180	28.4790
Final weight (g)	27.7714	28.1188	28.4791
Weight loss (mg)	759.4	299.2	-0.1
Weight loss (%)	2.66	1.05	0.00
Corrosion rate (mil/year)	671	265	0
Corrosion rate (μ/year)	1705	672	0
Corrosion rate (mm/year)	1.71	0.67	0.00

Applicant's summary and conclusion

Conclusions:

Perform CC: Aluminium coupons exhibited minimal corrosion equivalent to a maximum of only 0.01 mm/year in the fully immersed coupon. Some dark staining was evident, particularly at the air/liquid interface on the partially immersed coupon, and on surfaces in the vapour phase that became splashed with liquor owing to condensed water vapour dripping from the condenser into the test solution. There was no other visible evidence of corrosion.

Areas of the steel coupons that were directly exposed to Perform CC showed significant corrosion including light pitting. However, the measured corrosion rate of 1.71 mm/year on the fully immersed coupon was well within the 6.25 mm/year threshold specified by the test protocol. The liquor exhibited a red-brown bloom close to immersed coupon surfaces within fifteen minutes of starting the test, and was almost opaque deep red-brown in colour after three days.