Kinetic studies of asphaltene flocculation in asphalt-solvent solutions have recently been investigated using automated flocculation titrimetry (AFT).A new method was developed to measure rates of flocculation of asphaltenes in solutions of asphalt in toluene,titrated with iso-octane (2,2,4-trimethyl pentane).The flocculation rate process described by this method may be modeled using a simple second-order rate law (a bi-molecular rate equation) defined in terms of a forward rate constant,k,and an effective maximum number of flocculated particles,n_(max).This effective maximum number of flocculated particles is actually measured in terms of the maximum amount of UV-visible light blocked,(Abs_(adj))_(max),at 740 nm due to the formation of floes as a function of time.Measured values of (Abs_(adj)_(max)) correlate closely with "n-heptane defined" asphaltene content of whole asphalt,and thus,constitute a rapid measure of asphaltene content in whole asphalts.
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