Method of producing an additive increasing the cetane number of diesel oils

1. The method of producing an additive increasing the cetane number of diesel oils for self-ignition engines. Characterized in that: Aliphatic alcohols are estrified with nitric acid, preferably an estrifying mixture, while the mass ratio of alcohol to the estrifying mixture is between 1:1 and 1:10, preferably within the range of 1:1 to 1:4. The reacting substances are mixed for up to 1 hour, preferably 15 to 30 minutes, while alcohol is proportioned at the rate, which allows the reaction temperature to be maintained under 60 degrees C, preferably at 20 degrees C to 50 degrees C, until the content of nitrogen in the ready product is within the range of 4 to 15 percent by mass, preferably between 5 and 10 percent by mass. Then, the mixture is left to settle. Then, the organic phase is separated from the inorganic phase, and the former is rinsed several times with water and dried. 7. The method of producing an additive increasing the cetane number of diesel oils for self-ignition engines. Characterized in that: In a stream reactor, the streams of aliphatic alcohols and nitric acid, preferably an estrifying mixture, are mixed. The mass ratio of alcohol to the estrifying mixture is between 1:1 and 1:10, preferably within the range of 1:1 to 1:4. The time of contact of reacting substances is between 0.1 second to 5 minutes, preferably within the range of 0.5 to 30 seconds. The speed of the heterogenic mixture flow ensures the reaction temperature is maintained under 100 degrees C, preferably under 90 degrees C. The mixture is quickly cooled down to the temperature under 40 degrees C, preferably under 30 degrees C. The mixture undergoes the process of constant phase separation. The organic phase is subjected to the neutralization process and the neutralized product, containing from 4 to 15 percent of nitrogen, preferably 5 to 10 percent, is rinsed with water.