Evaluation of the effect of the fatty acid esterification product of tall oils on the properties of diesel fuel

Abstract

In conformity with a constant tightening of environmental requirements, sulfur compounds are removed from the composition of diesel fuel using the hydrotreating method. However, this has led to a significant deterioration in the anti-wear properties of diesel fuel. To restore the lubricity, oxygen-containing compounds are added to diesel fuel, including carboxylic acids and their amide derivatives, as well as esters, polyamines and other organic compounds. The recommended concentration of the additive, which ranges from 0.015 to 1.0 wt %, is dependent on its specific properties. In addition to anti-wear additives, cetaneenhancing, depressant-dispersing and other additives are added to diesel fuel to correct the properties of the fuel. A method for producing an esterification product for improving the properties of diesel fuel is described. It is shown that an esterification product containing up to 65% fatty acid esters can be obtained at a temperature of 110–115 °С and a process duration of 120–240 minutes when using 3–5 wt % ion-exchange resins for fatty acids. The effect of the additive content on the lubricating properties of diesel fuel is investigated. When 0.5 wt % or more is added, the corrected wear spot diameter is reduced from 615 to 420 µm; when 1.5 wt % is added, it is further reduced to 230 µm. The addition of esterification product to the diesel fuel is shown to result in an increase in the cetane number of initial fuel. When adding 6.0 wt % of the esterification product under development, the cetane number of the fuel is increased from the original 43.0 units to 51.6. In this case, the esterification product can be used as a component for preparing a mixture of biodiesel fuel B6-B20, according to GOST 33131-2014.