Sorption and microbial degradation of naphthalene in soil-water suspensions under denitrification conditions

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Environmental Science and Technology; (USA)

DOI:https://doi.org/10.1021/es00013a020· OSTI ID:5936840

Mihelcic, J R ^[1]; Luthy, R G ^[2]

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1. Michigan Technological Univ., Houghton (USA)
2. Carnegie Mellon Univ., Pittsburgh, PA (USA)

The microbial degradation of naphthalene under denitrification conditions in soil-water suspensions was dependent on solute partitioning between soil and water. Soil-associated naphthalene was in equilibrium with aqueous-phase solute, with the rate of naphthalene degradation being mixed order with respect to aqueous concentration. The rate of degradation was modeled by coupling Michaelis-Menten kinetics for aqueous-phase solute with an intraaggregate radial diffusion model for naphthalene sorption and desorption with soil. It was shown by modeling and confirmed by experiment, for the soil suspension particle sizes employed in these tests, that the naphthalene sorption-desorption process was reversible and rapid compared to the rate of microbial degradation. The maximum rate of microbial degradation was proportional to the soil-to-water ratio and independent of nitrate concentration for initial nitrate concentrations greater than several hundred micrograms per gram of soil. Nitrate reduction was described by utilizing the total mass removal of naphthalene and a stoichiometric conversion factor. A coupled solute desorption-degradation model is presented for microbial degradation of hydrophobic organic compounds that are desorbed from porous soil aggregates, assuming sorbed solute is inaccessible to microorganisms and that the rate of solute release from the solid is rapid compared to the rate of retarded intraaggregate diffusion.

• OSTI ID: 5936840
• Journal Information: Environmental Science and Technology; (USA), Journal Name: Environmental Science and Technology; (USA) Vol. 25:1; ISSN ESTHA; ISSN 0013-936X
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
540320 -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
AROMATICS
BIODEGRADATION
CHEMICAL REACTIONS
CONDENSED AROMATICS
DATA
DECOMPOSITION
DENITRIFICATION
ENVIRONMENTAL TRANSPORT
EXPERIMENTAL DATA
GROUND WATER
HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
MASS TRANSFER
MEASURING METHODS
NAPHTHALENE
NUMERICAL DATA
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
SOILS
SORPTION
WATER