Modification of the viscosity of extra-heavy crude oil using aqueous extracts of common geranium (Pelargonium hortorum)

Abstract

The transport of extra-heavy crude oil is a severe problem in the oil industry due to its viscosity, asphaltenes content, and tendency to precipitate. These crude oil's characteristics cause clogging of the pipes and increase production costs. One of the solutions for this problem is the addition of compounds that reduce the viscosity of crude oil and the self-aggregation of asphaltenes. In recent years, new ‘green’ additives have been investigated to replace the use of traditional and more toxic substances, such as toluene. In this study, new common geranium (Pelargonium hortorum) aqueous extracts were synthesized with 1, 5, and 10% (w/v). Its effect on the Mexican extra-heavy (8 °API) crude oil blend was analyzed in a shear rate range of 0.1–60 1/s and constant temperatures of 30, 40, and 50 °C. In addition, its pH, TDS, and EC were measured on days 1 and 15 after synthesis. These synthesized compounds were qualitatively determined using phytochemical analysis. The possible relationship between these compounds and the viscosity modification was analyzed. The results suggest that using these compounds as viscosity modifiers for extra-heavy crude oil could be promising, at higher concentrations in the range of 5–10% and for a temperature range of 40–50 °C, and for lower shear rates. The conclusions suggest further investigation of the common geranium aqueous extracts to understand its effect on crude oil properties.