Registration Dossier

Diss Factsheets

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Key study: Blanchar RW and Hossner LR (1969) 
The data show that sodium tripolyphosphate was strongly adsorbed. An estimate of the extent of hydrolysis during the sorption study was made by determining the phosphate content of the solution phase of the most concentrate sample.
Although considerable hydrolysis of TPP had taken place, an approximation of the sorption capacities were determined from the Langmuir adsorption isotherm.
The sorption capacity was 706 µg P/g soil

Key value for chemical safety assessment

Koc at 20 °C:
142.44

Additional information

The sorption capacity is equal to the amount of test substance (µg) adsorbed/amount of sorbent (g) at equilibrium

The Freundlich adsorption coefficient (Kf) is the log of this value

Koc=Kf/foc(µg/g)

Sorption capacity = 706

Kf = 2.85

focsoil = 0.02

Koc=2.85/0.02

Therefore Koc = 142.44 µg/g

Log Koc = 2.15