Abstract: The molecule characteristics of four resins and adsorption behavior of them on two asphaltenes are investigated.The interrelationship between the adsorption behavior of resins on asphaltenes and dispersing stability of asphaltenes is discussed.The results indicate that the adsorption isotherms of four resins follows the Freundlich equation.The shape of the curves obtained could be attributed to both multilayer adsorption of resins on asphaltene surfaces and the penetration of resins in the microporous structure of the asphaltenes.Furthermore，based on the combined results from shape of the curves and characteristics of resins，the plateau at low equilibrium concentration correspond to the formation of a close-packed monolayer at the adsorption isotherms of three resins (such as TH、BH and LH resin).As the concentration exceeds a certain threshold，there is a stronger polar of the resin，and the steeply rising part of the isotherms is related to the phase separation of resins themselves and indicates a higher affinity for the asphaltene than for the n-heptane.In contrast，HB resin can not give rise to phase separation with weaker polar，the penetration of the microporous structure of asphaltenes by HB resin and the surface available for adsorption expands proportionally with the amount of resin.The relationship between adsorption behavior and dispersing ability of the resins as asphaltene stabilizers shows that dispersing ability of the resins is not only related to their adsorbed amount on asphaltene particles but also to the molecular formation of resins.
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Key words: crude oil, asphaltene, resin, adsorption, dispersing ability