Reaction mass of Fatty acids, montan-wax and Fatty acids, montan-wax, sodium salts and Montan wax

Dissociation constant

Administrative data

Endpoint:

dissociation constant

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

August 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study (OECD TG 112).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 112 (Dissociation Constants in Water)

Test material

Test material information

Constituent 1

Reference substance name:

Montan waxes, type NaV 101

IUPAC Name:

Montan waxes, type NaV 101

Details on test material:

Test item. Licomont NaV 101

Results and discussion

Dissociating properties:

not determined

Any other information on results incl. tables

Test Description

Before starting with the measurements described in the SOPs some solubility tests were performed.

Different volumes of water were added to different amounts of the test item and stirred for 48 h (see Table 1).

10 ml of several solvents were added each to approximately 4-5 mg of the test item and stirred for a while (see Table 1).

Results

Table 1 summarises the results of the solubility tests with water and organic solvents.

Table 1: Solubility tests in water and organic solvents

Amount of test item (mg)	Solvent	Amount of solvent (ml)	Observations
9.79	Water	100	Not dissolved
9.82	Water	500	Not dissolved
9.33	Water	1000	Not dissolved
4-5	Methanol	10	Not dissolved
4-5	Acetonitrile	10	Not dissolved
4-5	Ethanol	10	Not dissolved
4-5	Acetone	10	Not dissolved
4-5	Toluene	10	Not dissolved
4-5	2-Propanol	10	Not dissolved
4-5	n-Heptan	10	Not dissolved
4-5	Xylene	10	Not dissolved
4-5	n-Decane	10	Not dissolved
4-5	n-Tetradecane	10	Not dissolved
4-5	2-Butanone	10	Not dissolved
4-5	1-Hexanol	10	Not dissolved
3	Propylene carbonate	25	Not dissolved

The solubility of the test item in water is <9.33 mg/L, in propylene carbonate <120 mg/L and in all other tested organic solvents <500 mg/L. No further solubility tests with lower amounts of the test item in the organic solvents were performed. Due to the fact that the test solutions for the determination of the dissociation constant can only contain 1% of a water miscible solvent, the concentration of the test item would be too low for detection either with the pH-electrode or with the UV-spectrometer. Due to the insolubility of the test item in water and organic solvents the determination of the dissociation constant could not be performed.

Applicant's summary and conclusion

Conclusions:

Due to the low solubility of the test item in water and in several organic solvents the dissociation constant pKa could not be determined according to the OECD Guideline 112 (Dissociation constants in water (1981)).

Executive summary:

The objective of this study was the determination of the dissociation constant of the test item according to OECD Guideline 112, Dissociation constants in water (1981). Due to the low solubility of the test item in water and in organic solvents, the dissociation constant pK_a could not be determined according to the OECD Guideline 112.