PMID- 19534119
OWN - NLM
STAT- MEDLINE
DCOM- 20090707
LR  - 20190715
IS  - 0013-936X (Print)
IS  - 0013-936X (Linking)
VI  - 43
IP  - 9
DP  - 2009 May 1
TI  - LFERs for soil organic carbon-water distribution coefficients (Koc) at 
      environmentally relevant sorbate concentrations.
PG  - 3094-100
AB  - Organic carbon-water distribution coefficients, Koc, for organic compounds at 
      environmentally relevant, low sorbate concentrations may substantially differ 
      from those at higher concentrations due to nonlinear sorption to soil organic 
      matter. However, prediction methods for Koc such as linear free energy 
      relationships (LFERs) are currently only available for high sorbate 
      concentrations (i.e., near solubility limits), reflecting the lack of a set of 
      consistent experimental data in an environmentally more relevant concentration 
      range (i.e., orders of magnitude lower than solubilities). In this study, we 
      determined Koc for two model sorbents of soil organic matter, peat and lignite, 
      at sorbate concentrations of 4.3 and 19 mg/kg-organic-carbon, respectively, in 
      batch suspensions. The measured Koc values for organic sorbates (51 for peat, 58 
      for lignite) of varying sizes and polarities were modeled successfully with 
      polyparameter linear free energy relationships (PP-LFERs). The resulting PP-LFER 
      for peat was significantly different from the PP-LFERs in the literature 
      determined at near aqueous solubility limits of sorbates. The literature PP-LFERs 
      were found to underestimate the measured Koc values for peat at the low 
      concentration by up to 1 order of magnitude. The extent of underestimation highly 
      depends on the sorbate properties and can be explained by differing sorption 
      nonlinearities of the sorbates as predicted by a reported empirical relationship 
      between the nonlinearity in peat and the sorbate dipolarity/polarizability 
      parameter S. Lignite appearsto be a stronger sorbent toward many sorbates than 
      typical soil organic matter irrespective of the concentration range and thus may 
      not be representative for organic matter with regard to the magnitude of Koc. The 
      present study offers the first PP-LFER equation for log Koc in soil organic 
      matter at typical environmental sorbate concentrations.
FAU - Endo, Satoshi
AU  - Endo S
AD  - Center for Applied Geoscience, Eberhard-Karls-University of Tubingen, 
      Sigwartstrasse 10, D-72076 Tubingen, Germany. satoshi.endo@ufz.de
FAU - Grathwohl, Peter
AU  - Grathwohl P
FAU - Haderlein, Stefan B
AU  - Haderlein SB
FAU - Schmidt, Torsten C
AU  - Schmidt TC
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Environ Sci Technol
JT  - Environmental science & technology
JID - 0213155
RN  - 0 (Coal)
RN  - 0 (Soil)
RN  - 059QF0KO0R (Water)
RN  - 7440-44-0 (Carbon)
SB  - IM
MH  - Adsorption
MH  - Carbon/*chemistry
MH  - Coal
MH  - *Environment
MH  - Kinetics
MH  - *Soil
MH  - Thermodynamics
MH  - Water/*chemistry
EDAT- 2009/06/19 09:00
MHDA- 2009/07/08 09:00
CRDT- 2009/06/19 09:00
PHST- 2009/06/19 09:00 [entrez]
PHST- 2009/06/19 09:00 [pubmed]
PHST- 2009/07/08 09:00 [medline]
AID - 10.1021/es803157e [doi]
PST - ppublish
SO  - Environ Sci Technol. 2009 May 1;43(9):3094-100. doi: 10.1021/es803157e.