The influence of the physicochemical properties of diesel fractions on the effectiveness of the action of a cetane-enhancing additive, such as density, viscosity, sulfur content, boiling point (10%, 50%, 90%), molecular weight, and the choice of the required amount of additive for effective modification of the cetane number, were studied. To increase the cetane number, three different cetane improvers were used in this work. Three samples from various refinery units were used as the main base fuel:2-EGN(additives №1); № 2- AlH and № 3-AmH.For each sample, an increase in the cetane number of  diesel fuel is shown depending on the concentration of additive № 2. It was noted that an increase in the amount of additives to 2.5% leads to an increase in the cetane number in all three samples. Of all the additives studied in the tested samples, additive № 1 turned out to be the best cetane-enhancing.The image of thecetane numbers of samples (№1 - № 3 with additives №1 - №3, are presented in the form of tables.The change in the cetane numbers of the samples is from 51 to 54. The scope of application is also indicated in the work: laboratories, and oil refineries, to obtain diesel fuel with specified cetane number parameters

doi.org/10.32737/0005-2531-2023-2-104-110