title: Adsorption Isotherms of Bitumen/Aqueous Solutions of Intan-100
abstract: Adsorption isotherms for pure bitumen/aqueous solution of the non-ionic surfactant Intan-100 have been determined as a function of temperature using enhanced video pendant drop technique. The area/molecule occupied by the surfactant at the bitumen/water interface is about 3 times higher at 30&deg;C than at 60&deg;C at which maximum packing occurs. Isotherms for the model system heptane/aqueous solutions of Intan-100 indicate that maximum packing is not possible in the temperature range 20-60&deg;C. This fact implies that bitumen/water interface is a unique system where the natural surfactant present in the bitumen is playing a competitive role at the interface.
authors.affiliation: Department of Production, Intevep, S.A., Caracas, 1070-A, Venezuela
authors.initials: RA
authors.lastname: Mohammed
authors.initials: MD
authors.lastname: Lorenzo
authors.initials: J
authors.lastname: Mari&ntilde;o
authors.initials: J
authors.lastname: Cohen