The effect of hydrogen bonds between flow improvers with asphaltene for heavy crude oil

A series of chemical products with characteristic groups in molecular structures were synthesized as novel flow improvers (FIs) for heavy asphaltenic crude oil. The rheological measurement results showed that the FI-5 could behave the better performance in improving fluidity of heavy oil than FI-2 due to the former could form stronger hydrogen bonds with asphaltene in oil, which was confirmed through Fourier transform infrared spectroscopy (FTIR) and energy of simulating studies. Furthermore, X-ray diffraction (XRD) analysis results demonstrated that two products altered asphaltene structure at different degree through hydrogen bonding interaction, and the aggregation-dispersion effect of FIs on asphaltene were respectively obtained through scanning electron microscope (SEM), which beneficially weakened the stable structure of asphaltene in the heavy crude oil system . Hence, the mechanisms were tried to propose that could explain the phenomenon in rheological measurement why FI-2 was not as good as FI-5 in improving fluidity of heavy oil. Results also indicated that the asphaltene content and aggregation structure in oils were vital parameters for its viscosity.