Synthesis and evaluation of some polymeric surfactants for treating crude oil emulsions - Part I: treatment of sandy soil polluted with crude oil by monomeric and polymeric surfactants

In the present work, five surfactants were prepared; two of them were monomeric surfactants, one was anionic (tri-ethanol ammonium salt of dodecyl benzene sulfonic acid, E-1) and the second was non-ionic surfactant (nonyl phenol ethoxylate,E-2). The other three surfactants were polymeric non-ionic surfactants (ethoxylated polynonyl phenol formaldehyde mono-ethanol amine E-3, ethoxylated poly nonyl phenol formaldehyde diethanol amine E-4, and ethoxylated nonoyl phenol formaldehyde triethanol amine E-5). The gel permeation chromatography (GPC) and the elemental analysis were carried out to determine the molecular weight of the polymeric surfactants. The surface properties for these surfactants were determined by measuring the surface tension, the interfacial tension, the foaming power, cloud point and the emulsification power. The polymeric surfactants were used to treat the polluted sandy soil, which saturated with two types of crude oils (waxy and asphaltenic). From the data obtained it was found that, the increasing of surfactant concentrations led to increase the reclaimation of the waxy and asphaltinic crude oil percentages and decreased the interfacial tension. The reclaimed oil percentage increased with decreasing the hydrophilic-lipophilic balance (HLB) value of non-ionic surfactant. In general behavior, the reclamation of the asphaltenic crude oil was greater than the reclaimation of the waxy crude oil. The data were discussed on light of the chemical structure of the surfactants and composition of crude oil. (C) 2002 Elsevier Science B.V. All rights reserved.