Registration Dossier

Diss Factsheets

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Endpoint:
adsorption / desorption
Remarks:
adsorption/desorption
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: acceptable, well documented publication which meets basic scientific principles

Data source

Reference
Reference Type:
publication
Title:
Adsorption of Substituted Nitrobenzenes and Nitrophenols to Mineral Surfaces.
Author:
Haderleln S.B. and Schwarzenbach R.P.
Year:
1993
Bibliographic source:
Environ. Sci. Technol., Vol. 27, No. 2, pp. 316-326

Materials and methods

Principles of method if other than guideline:
The adsorption of a large number of nitroaromatic compounds (NACs) (e.g. 4-chloronitrobenzene) to mineral surfaces, particularly to homoionic kaolinites, has been investigated.
GLP compliance:
no
Type of method:
HPLC estimation method
Media:
other: mineral surfaces, particulary to homoionic kaolinites

Test material

Constituent 1
Chemical structure
Reference substance name:
1-chloro-4-nitrobenzene
EC Number:
202-809-6
EC Name:
1-chloro-4-nitrobenzene
Cas Number:
100-00-5
Molecular formula:
C6H4ClNO2
IUPAC Name:
1-chloro-4-nitrobenzene

Results and discussion

Results: Batch equilibrium or other method

Adsorption and desorption constants:
Kd = 44 l/kg

Any other information on results incl. tables

An apparent sorption equilibrium was always attained within a few minutes. After this time no detectable concentration changes occurred; thus typical equilibration times between 30 ¿ 60 minutes were used in all experiments. Desorption kinetics of NACs were also investigated, and it was also found that desorption equilibrium was reached within a few minutes. The results demonstrate that nitroaromatic compounds may adsorb specifically and reversible to the negatively charged siloxane surface of kaolinite. At high surface coverage the adsorption isotherms generally exhibit a saturation-type curvature approaching a maximum surface concentration of ca. 2.5 mmol of NAC/kg of kaolinite. At low surface coverage the isothermes were linear and a constant distribution coefficient Kd (L/kg), can be defined for this part of the isotherm. The Kd calculated for p-chloronitrobenzene is 44 l/kg.

Applicant's summary and conclusion