Characterization of Asphaltene Fractions: Distribution, Chemical Characteristics, and Solubility Behavior

In this work, we present a series of correlations between physical and chemical properties of asphaltenes based on extensive characterization of asphaltene solubility fractions from diverse origins. Additionally, an effort is made to identify the key chemical/molecular characteristics that make materials prone to asphaltene precipitation. It was found that high hydrogen deficiencies and uneven asphaltene fraction distributions are the main contributors to asphaltene instability. The correlations found among asphaltene properties indicate that it is possible to estimate some of these properties using the solubility profile as a unique test. In particular, this technique can provide good solubility parameter estimates without preparative isolation of the asphaltenes, and—besides providing average values—it can also give solubility parameter distribution which might be useful in considering asphaltene polydispersity for modeling purposes. The main advantage of this test is that it does not require previous separation of the asphaltenes.