Adsorption of Asphaltenes on Metals

Abstract

The adsorption of Athabasca and Cold Lake C 7 -asphaltenes on stainless steel (304L), iron, and aluminum powders was measured using UV-vis spectrophotometry. The effects of resins, temperature, and n-heptane-to-toluene ratio were also investigated. In all cases, Langmuir (type I) isotherms were observed, indicating that asphaltenes saturated the available surface area for adsorption. The saturation adsorptions of the asphaltenes on metals (0.25-2.7 mg/m 2 ) were of the same order of magnitude as adsorption of asphaltenes on minerals. The saturation adsorptions were less than the monolayer surface coverage observed on water-in-hydrocarbon emulsion interfaces, indicating that there are a limited number of adsorption sites on the metals. Higher molar saturation adsorptions were observed for resins and low molar mass asphaltenes, suggesting that adsorption was limited by the morphology of the metal surface. In general, higher mass saturation adsorptions were observed when asphaltenes self-associated to greater extents and consequently larger molecules adsorbed on the surface.

A model to calculate the average interaction energy and adhesion force between petroleum asphaltenes and some metallic surfaces

“…6-8 show the best-fit curves (continuous lines) as compared to the respective MM calculations (full squares) for the binary systems asphaltene-Fe, -Al, -Cr corresponding to the three metal substrates studied in this work. From these figures one can see that the well depth in the interaction energy between an asphaltene molecule and one Fe atom is deeper than for Al and Cr, this being in accordance with results from similar systems [24][25][26].…”

Asphaltene fractionation based on adsorption onto calcium carbonate: Part 1. Characterization of sub-fractions and QCM-D measurements

“…[40] Asphaltenes from Athabasca and Cold Lake have shown almost twice as high adsorption onto stainless steel than on iron. [39] Asphaltene adsorption of upto 5 mg/m 2 has been observed on iron oxide surface. [46] However, multilayer adsorption of asphaltenes onto mineral surfaces (Bedford limestone, Berea sandstone and dolomite) with adsorbed values in the range 100 -200 mg/m 2 at very high asphaltene concentrations in toluene has also been reported.…”

“…[32] The adsorption of asphaltenes onto surfaces (mineral and metallic) is an undesired phenomena in the petroleum industry as it can lead to formation damage [32], wettability alteration [33], plugging of wells and flow-lines [34,35]. Several techniques have been used to study the adsorption of asphaltenes onto solid surfaces including quartz crystal microbalance (QCM) [36][37][38] and UV-vis spectroscopy [39,40]. The ability of asphaltenes to adsorb as monolayer [41] as well as multiple layers [41][42][43][44][45] has been reported in literature.…”

Adsorption and Aggregation of Asphaltenes in Petroleum Dispersed Systems

“…Asphaltene and resin adsorption was studied by a great number of research groups (Ekholm et al, 2002;TatNIPI, 1988;Balabin&Syunyaev, 2008;Syunyaev et al, 2009;Acevedo et al, 2000;Lopez-Linares et al, 2006;Gonzalez&Middea, 1987;Drummond&Israelachvili, 2004;Toulhoat et al, 1994;Akhlaq et al, 1997;Dudasova et al, 2007;Alboudwarej et al, 2005;Batina et al, 2003;Batina et al, 2005;Castillo et al, 1998;Acevedo et al, 1998;Acevedo et al, 2000;Acevedo et al, 2003;Ekholm et al, 2002;Xie&Karan, 2005;Dudasova et al, 2008;Rudrake et al, 2009;Abdallah&Taylor, 2007;Labrador et al, 2007;Turgman-Cohen et al;. Adsorption of asphaltenes on solid surfaces has been characterized by several experimental techniques, including measurement of contact angles (Drummond & Israelachvili, 2004;Toulhoat et al, 1994;Akhlaq et al, 1997), UV and NIR spectroscopy (Dudasova et al, 2007;Alboudwarej et al, 2005), atomic force microscopy (Toulhoat et al, 1994;Batina et al, 2003;Batina et al, 2005), Fourier transform infrared microscopy (Batina et al, 2005), photothermal surface deformation Acevedo et al, 1998;Acevedo et al, 2000;Acevedo et al, 2003), quartz microbalance (Ekholm e...…”

“…Adsorption of asphaltenes on solid surfaces has been characterized by several experimental techniques, including measurement of contact angles (Drummond & Israelachvili, 2004;Toulhoat et al, 1994;Akhlaq et al, 1997), UV and NIR spectroscopy (Dudasova et al, 2007;Alboudwarej et al, 2005), atomic force microscopy (Toulhoat et al, 1994;Batina et al, 2003;Batina et al, 2005), Fourier transform infrared microscopy (Batina et al, 2005), photothermal surface deformation Acevedo et al, 1998;Acevedo et al, 2000;Acevedo et al, 2003), quartz microbalance (Ekholm et al, 2002;Xie&Karan, 2005;Dudasova et al, 2008;Rudrake et al, 2009), X-ray photoelectron spectroscopy (Dudasova et al, 2007;Abdallah&Taylor, 2007) and ellipsometry (Labrador et al, 2007;Turgman-Cohen et al, 2009). In this study we studied influence of porosity of the rock on adsorption parameters of the asphaltenes.…”