Test Method for Oxidation Stability of Gasoline
Automotive gasoline is a hydrocarbon mixture refined from light petroleum fractions. Under normal conditions, it is a transparent or translucent clear liquid with volatile and flammable properties. Its density is usually less than that of water, approximately 0.70～0.78 g/cm³ (the specific value may vary depending on the type of gasoline and temperature), and its distillation range is 30℃ to 205℃. The main components are C5～C12 alkanes and naphthenes, which are widely used in the transportation industry.
Experimental Purpose
By determining the oxidation stability of gasoline, we can evaluate its ability to resist oxidative deterioration during storage, transportation, and use. This ensures the stability and safety of product quality, extends service life, and reduces engine failures. The experiment is conducted in accordance with the induction period method specified in GB/T 8078-2015, and the SH8018 Gasoline Oxidation Stability Tester complies with this standard, which is used for the test.
Experimental Instruments
① SH8018 Gasoline Oxidation Stability Tester
② Optional accessories such as toluene, gum solvent, and oxygen bomb that meet the requirements of GB/T 8018 and ASTM D525
Experimental Procedures
① Start the instrument, set the experimental parameters, and take the experimental sample.
② When the oxygen bomb and oil sample reach 15-25℃, place the glass sample bottle containing 50ml±1ml of oil sample into the oxygen bomb, cover the sample bottle, and tighten the oxygen bomb. Purge the gas inside the bomb with oxygen as required, then slowly introduce oxygen to adjust the pressure inside the bomb to 690kpa-705kpa, and check for leaks.
③ If there is no leakage, place the oxygen bomb into a metal bath with a temperature of 98℃-102℃. Record the time when it is immersed in the metal bath as the start time of the experiment, and continuously record the pressure inside the oxygen bomb until the inflection point is reached.
④ Automatically calculate the induction period of the sample at 100℃ and print the result.
⑤ Take out the oxygen bomb, let it cool down statically in an environment not exceeding 35℃, release the pressure, and clean and organize the instruments used in the experiment.
Experimental Results
Through measurement and analysis, the induction period of the gasoline is greater than 480 minutes under the conditions of 100℃ and oxygen pressure of 690kpa-705kpa, which meets the standard requirements.
