Analysis of the Relationship between the Low-Temperature Properties and Distillation Profiles of HEFA-Processed Bio-Jet Fuel

Abstract

The greenhouse gas (GHG) emission mandate on jet fuel requires a gradual reduction in the fuel’s GHG emissions, up to 50%, by 2050. For this reason, the demand for bio-jet fuel blended with conventional petroleum-derived jet fuel will increase. In order to meet the quality requirement of blended fuels (ASTM D7566), modeling that can predict the correlation between properties is required. Our aim was to predict the low-temperature properties using the distillation profile results obtained from Simulated Distillation (SIMDIS) according to the carbon number and chemical compositions of bio-jet fuel through correlation and regression analysis. We used hydroprocessed ester and fatty acid (HEFA) bio-jet fuel and hydrocarbon reagents that included C8, C10, and C12 carbons and five main families of hydrocarbons for blended jet fuel. This study shows an overall trend for each component, indicating that the distilled volume fraction is more affected than the carbon number. In the case of the freezing point, by composition, n-paraffin and naphthene have regression coefficients of more than 0.85 for the 50% and 60% recovery temperatures, respectively. In terms of carbon number, the C8 sample has a significant regression coefficient for the 40% recovery temperature, and C10 has a significant regression coefficient for the initial boiling point (IBP) and 10% recovery temperature. In the case of kinematic viscosity, by composition, the regression coefficient is significant for the 20% to 40% recovery temperatures. For naphthene, the kinematic viscosity exhibited no relationship with carbon number. This information can be utilized to determine the blended ratio of bio-jet fuel and conventional jet fuel in newly certified or commercial applications.

Relation of the Content of Sustainable Components (HEFAs) in Blends with Hydrotreated Straight-Run Kerosene to the Properties of Aviation Fuel

“…Several relations between the properties (their range is presented in Table 1) of commercial batches of mineral turbine fuel-JET A-1-produced by the European refinery can be derived. Distillation (ASTM D86) temperatures for the lowest boiling point components in mineral aviation fuel-both IBP and 10% distilled-are strongly correlated [33]; their squared correlation coefficient is R 2 > 0.87, with the lowest temperature being that at which the vapors above JET A-1 will ignite on the application of an ignition source-flash point. The straight line in Figure 3a describes the correlation between IBP and the flash point, the The slope of the straight line dependence between the 10% distilled and flash point is 0.92 and is pointed out in Figure 3b.…”

“…Initiative RefuelEU, its update in Regulation (EU) 2023/2405, and the period thereafter are accompanied by a detailed study on the production and effect of synthetic components [1][2][3]8, and especially HEFAs [3,7,8,[13][14][15][16][17][19][20][21][22][24][25][26][27][28]30,[32][33][34][35] on their blends with fossil aviation fuel properties. Some of the publications [14,15,20,[30][31][32] reveal the effects of chemical composition on jet fuel performance characteristics.…”

“…The arene content [14,16] seems to have a critical influence on its physicochemical properties. Bio-jet fuels possess satisfactory low-temperature fluidity [33]-low freezing point [16,20,22,30,31] (due to high content of iso-paraffins)-and viscosity [17,20,30]. They are reported in the literature [14] to have favorable thermal stability but relatively poor oxidative stability due to the absence of heteroatom-containing compounds and oxidatively stable arenes.…”

“…Other properties like total acid number, water content, differential scanning calorimetry, surface tension [17], copper corrosion rating, and existent gum [31] are infrequently reported. Most of the references [16,17,22,31,33] describe some properties only for fossil fuels, or only for SAFs, and few references [14,30] report some of the target properties of fossil/SAF blends. Not a single reference that fully characterizes (as per all ASTM D1655 requirements) fossil/SAF blends can be found.…”