Allyl ester-based liquid crystal flow improvers for waxy crude oils

Abstract

Crude oil pretreatment using flow improver or pour point depressants has been accepted considerably owing to its simplicity and economy. We prepared herein new allyl 4-(dodecyloxy) benzoate I12 and allyl 4-(octadecyloxy) benzoate I18. Moreover, we synthesized the homopolymer of the prepared ester and prepared copolymers with dioctadecyl maleate by free-radical polymerization using toluene as solvent and azobisisobutyronitrile as initiator. These compounds are characterized by Fourier-transform infrared (FT-IR) and Differential scanning calorimeter (DSC) used to determine the properties of the liquid crystal. The prepared polymers at different concentrations are tested as flow improvers for Qarun crude oil (QN) through pour point depression and rheological parameters. Results demonstrate that polymers’ alkyl chain length significantly affects the pour point, where MHI18 manifests the highest pour point reduction. Effects on the rheological properties increase with the alkyl chain length increase, where the highest reduction of both yield value and apparent viscosity is attained with poly (4 Octadecyloxy allyl benzoate co Dioctadecyl maleate) MHI18. The additive efficiency increases as the additive concentration increases from 1000 to 5000 ppm. Copolymerization with dioctadecyl maleate increases the efficiency of the prepared polymers.

Graphical Abstract

Highlights

• Prepared compounds were characterized by different analyses

• Prepared compounds were used as flow improvers for Qarun waxy crude oil

• Wax crystals became small and dispersed after treatment with poly liquid crystal

• Copolymerization with dioctadecyl maleate increased the compound efficiency

Keywords:

• Allyl benzoate
• DSC
• pour point depressant
• viscosity
• wax crude oil

Additional information

Funding

The authors gratefully acknowledge financial support from Taif University Researchers Supporting Project number (TURSP-2020/135), Taif University, Taif, Saudi Arabia.