Influence Of Compounds Containing Nitrogen,sulfur And Oxygen On The Oxidation Stability Of Oil

Oxidation stability is an important basis for measuring the quality of fuel oils such as gasoline and diesel fuel.There are three commonly used fuel oxidation stability test methods.They are jet evaporation method and induction period method and accelerated method.These three test anti-methods reflect the oxidation stability of the fuel from the existent gum,induction period and insoluble content.There are many factors that affect the oxidation stability of oil products,such as chemical composition,processing technology,environmental factors in storage and use,among which chemical composition is the key factor affecting the oxidation stability.The chemical compositions that affect the oxidation stability of fuels are mainly unsaturated hydrocarbons,nitrogen-containing compounds,sulfur-containing compounds,and oxygen-containing compounds.In this paper,representative compounds containing nitrogen,sulfur,oxygen and unsaturated bonds was quantitatively added in a stable mineral oil(D40).The specific effects of different substances on different oxidation stability test methods were clarified,and the quantified relationship among these three elements and the effect of unsaturated bonds on the oxidation stability of oils was obtained,in which the nitrogen-containing compound diallylamine has the greatest impact on the oxidation stability.Unsaturated hydrocarbons and heteroatoms work together to affect oxidation stability more than only unsaturated hydrocarbons and only heteroatoms.The study found that the effect of the same substance on the oxidation stability exhibited by different test methods is different.It is necessary to comprehensively investigate the oxidative stability of mineral oil.Analytical instruments such as nuclear magnetic resonance,infrared spectroscopy,and ultraviolet spectroscopy were used to obtain the chemical composition of the oil before and after oxidation,and the roles played by different groups in the oxidation of oils were determined.A comparison experiment was conducted on the three oxidation stability test methods and the connection among different test methods was established.In the jet evaporation method,the change tendency of the existent gum content and the insoluble content in the acceleration method is the same.However,there is no direct connection among the induction period and the existent gum content and the insoluble content.It provides a meaningful reference for the processing,storage,transportation and use of oil products.