Surface chemical aspects of oil spill sedimentation : final report. API Publication.

American Petroleum Institute.
Wilson, David. Putnam, Frederick A.

1985

663
CIENA

Experimental study was undertaken to determine the importance of surfactants to crude oil uptake by marine sediments. Parameters varied included duration of agitation, salt concentration, sediment particle size, and type and concentration of surfactant. Other aspects of oil sedimentation were investigated via gas chromatography, mocroscopy, contact angle measurements, in the presence of surfactants. An attempt was also made to reproduce the observations of other research, where in dispersants added during similar experiments increased oil sedimentation. In the absence of surfactants, data for oil uptake was found to be very inconclusive for agitation times less than 60 min. Seawater salinity reduced oil uptake by about 50 percent compared to distilled water. This agrees with other results and is apparently caused by the kinetics of oil particle formation from the oil slick. Using smaller particle sizes greatly increased oil uptake, because of a reduction of shear forces that tend to separate flocculated oil from sediment particles. Adding even small amounts of surfactant reducen oil uptake for sediments by two orders of magnitude. Typically this required only 0.003 m1 (0.001 vol. per cent) of surfactant, regardless of its composition. This is explained in terms of the superposition of the potential energy vs. separation curves for three interparticle forces; Van der Waasls attraction, electrical double-layer repulsion, and entropic repulsion. Chromatography and microscopy results indicate that oil transport to sediments is mainly via particle-particle association, as opposed to molecular (or film-wise) adsorption...Ver documento. Fate of petroleum. Sedimentation research. Surface charge research. THEORY. Surface tension and thermodynamics. Colloidal phenomena. The van der Waals Force. Double-layer forces. Entropic repulsion. Mixing. Denting. Combined effects. Simultaneous van del Waals, double-layer, and entropic repulsion interactions. EXPERIMENTAL. Agitation experiments. Spectrophotometry. Gas chromatography. Surface tension. Contact angle. Dispersants. Attempt to duplicate reed's results. DISCUSSION. Agitation experiments. Salt effect. Sediment size. Dispersant concentration. Surface tension. Contact angle. Attempt to duplicate reed's results.

Presenta tbls. y gráfs.

GENERAL; DERRAMES DE PETROLEO; PETROLEO; SEDIMENTACION; ANALISIS QUIMICO; EXPERIMENTOS; SEDIMENTOS MARINOS;