Submitted to: Energy and Fuels
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2004
Publication Date: 7/21/2004
Citation: Sharma, B.K., Adhvaryu, A., Sahoo, S.K., Stipanovic, A.J., Erhan, S.Z. 2004. Influence of chemical structures on low temperature rheology, oxidative stability, and physical properties of group II and III base oils. Energy and Fuels. 18(4):952-959. Interpretive Summary: Base oil is a major constituent of any lubricating oil and is derived from crude petroleum sources. Due to advancement in refining and processing technology, fluids with better performance properties are produced. Current knowledge on these fluids is limited and therefore a detailed study is required before extensive product development is planned. The current study attempts to establish structure - property relationship of these new generation fluids. Various evaluation and characterization protocols have been used to obtain molecular composition of these fluids. The structural information was used to develop meaningful relationship for cold flow, oxidation and other physical properties of these base oils. This study will directly benefit vegetable and mineral oil industry in selecting base fluids to meet future product specifications. Similar studies can be extended to various seed oils to increase their share in non-food uses and improve the local agro-economy.
Technical Abstract: The effect of base oil composition on lubricant properties has been studied to better understand low temperature rheology, oxidative stability and other physical properties. A simple approach has been adopted using low temperature rheology to develop multi-linear regression model to estimate Brookfield viscosity. Six base oils from API groups II and III were studied using different nuclear magnetic resonance spectroscopy methods. One method involved determination of average structural parameters from quantitative 13C NMR data, while the other method involved measurement of spin-lattice relaxation times at variable temperatures. The structural information obtained from these two methods was used to develop meaningful correlations for low-temperature, oxidative and physical properties of these base oils. The study suggests that a deeper knowledge of chemical composition will help in selecting base oils to meet future product specifications.