Premium
Effects of Cations on Complexation of Naphthalene by Water‐Soluble Organic Carbon
Author(s) -
Traina Samuel J.,
Spontak Donna A.,
Logan Terry J.
Publication year - 1989
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq1989.00472425001800020016x
Subject(s) - chemistry , naphthalene , inorganic chemistry , aqueous solution , ionic strength , water soluble , quenching (fluorescence) , total organic carbon , stoichiometry , fluorescence , nuclear chemistry , environmental chemistry , organic chemistry , physics , quantum mechanics
The effects of cation type (Na, Ca, or Al), pH, and stoichiometric ionic strength ( I s ) on the complexation of naphthalene (in ClO − 4 media) by water‐soluble soil organic matter extracted from a muck soil (Euic, mesic Typic Medisaprist) were investigated with a fluorescence quenching technique. Decreases in the intrinsic fluorescence of the naphthalene, resulting from additions of water soluble soil organic matter (0–28 mg L −1 C expressed as water‐soluble organic carbon or WSOC) were used to calculate conditional naphthalene‐WSOC stability constants ( c K oc ) for each of the electrolyte systems investigated. For all cases, increased aqueous concentrations of WSOC caused an increase in the formation of naphthalene‐WSOC complexes. Changes in pH value from 1.5 to 7.3 (in the presence of 0.05 mol L −1 NaClO 4 ) and changes in I s from 0.05 to 0.5 mol L −1 [in the presence of either Ca(ClO 4 ) 2 or Al(ClO 4 ) 3 ] had no effect on the binding of naphthalene by WSOC. In homoionic systems of either NaClO 4 , Ca(ClO 4 ) 2 , or Al(ClO 4 ) 3 ) (for I s = 0.05 mol L −1 ), the formation of naphthalene‐WSOC complexes decreased in the order Na = Ca > Al. The effect of Al on the binding of naphthalene by WSOC may have resulted from changes in the physical, polymeric structure of WSOC molecules caused by the presence of Al as a counter ion.