Sorption of binary mixtures of aromatic nitrogen heterocyclic compounds on subsurface materials

Journal Article · Wed Apr 01 04:00:00 EST 1987 · Environ. Sci. Technol.; (United States)

DOI:https://doi.org/10.1021/es00158a010· OSTI ID:6711628

Zachara, J M; Ainsworth, C C; Cowan, C E; Thomas, B L

Single and binary solute sorption of pyridine, quinoline, and acridine has been investigated on two low organic carbon subsurface materials with similar properties but different equilibrium pH when saturated with water. Single solute sorption for all compounds is higher in the acidic soil as compared to the basic soil, reflecting stronger sorption of the protonated organic cations. The protonated species exhibit high selectivity for the exchange complex at low aqueous concentration with selectivity increasing with ring number. Binary sorption experiments with quinoline/pyridine and quinoline/acridine demonstrate that competitive sorption occurs between compounds in the acidic subsoil where the protonated compounds species predominate in solution. In contrast, competition is minimal in the basic subsoil when the compounds are neutral. The competition between compounds is consistent with their measured single solute sorption and suggests mass action on a common set of high-affinity surface sites. A simplified model based on ideal absorbed solution theory (IAS) is used to provide simulations of binary solute sorption that are in good qualitative agreement with experimental results. It is suggested that competition between ionized solutes may significantly influence transport of organic mixtures when the groundwater pH is near the pK/sub a/ of the compounds. 31 references, 7 figures, 6 tables.

• Research Organization: Pacific Northwest Lab., Richland, WA
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6711628
• Journal Information: Environ. Sci. Technol.; (United States), Journal Name: Environ. Sci. Technol.; (United States) Journal Issue: 4 Vol. 21:4; ISSN ESTHA
• Country of Publication: United States
• Language: English

Related Subjects

510200* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACRIDINES
AROMATICS
AZAARENES
AZINES
CATIONS
CHARGED PARTICLES
CHEMISTRY
DATA
DISPERSIONS
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
IONS
MATHEMATICAL MODELS
MIXTURES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PH VALUE
PYRIDINES
QUINOLINES
SOIL CHEMISTRY
SOILS
SORPTIVE PROPERTIES
SURFACE PROPERTIES