Synthesis and performance evaluation of poly (fatty esters-co-succinic anhydride) as pour point depressants for waxy crude oils

Abstract

This research work focuses on the development of two polymeric compounds poly (n-dodecyl linoleate –co- succinic anhydride) and poly (n-dodecyl ricinoleate –co- succinic anhydride) from the naturally obtained vegetable oils fatty acids, which were subsequently evaluated as pour point depressants (PPDs) for a waxy crude oil. The developed chemical additives were characterized by FTIR and NMR spectroscopies. Significant reduction in pour point and apparent viscosities were obtained for the PPD treated crude oils compared to virgin crude oil, which indicated improvement in low temperature flow properties of the crude oil. Moreover, reduction in gelation point, storage and loss modulus of PPD treated crude oils exhibit improvement in the restart flowability of crude oil in case of pipeline shut down. Microscopic studies revealed the changes in the wax crystal structures after addition of chemical additives. One of the important studies, cold finger test showed that, wax deposition from the crude oil was considerably reduced by the addition of the two synthesized PPDs during flow through tubing, resembling the pipeline flow condition.