Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/21/2004
Publication Date: 1/1/2006
Citation: Erhan, S.Z., Adhvaryu, A., Sharma, B.K. 2006. Chemically functionalized vegetable oils. In: Rudnick, L.R., editor. Synthetics, Mineral Oils, and Bio-Based Lubricants, Chemistry and Technology. Boca Raton, FL: CRC Press. p. 361-387. Interpretive Summary: The uncertainty in petroleum supply along with pollution and environmental health concerns is making a way for vegetable oils to be used as fuel and lubricants. The vegetable oils have some advantages like naturally renewable resource, environmentally safe, good lubricity and viscosity-temperature characteristics along with disadvantages such as poor cold flow behavior, low oxidation stability. This chapter describes the various chemical ways to improve some of these properties of vegetable oils. The improvement in different properties and their applications is described in detail. The improved vegetable oils can be used in almost all automotive and industrial applications with additional advantage of being clean, biodegradable and non-toxic. With new strategies, policies and subsidies, a tremendous demand of these oils in lubricant sector is expected over the next few years and this will help reduce vehicle emissions, long-term environmental cleanup costs and dependence on mineral oil (a non-renewable natural source). The effect of pollution on the quality of life for people throughout the world is immeasurable.
Technical Abstract: The depletion in world petroleum reserves and uncertainty in petroleum supply due to political and economical reasons stimulated the search for alternative energy sources. In recent years, pollution and environmental health concerns have become a major debatable topic due to deliberate and accidental lubricant losses to environment including evaporation, leakages and spills. Thus, strict specifications on various environmental matters such as biodegradability, toxicity, occupational health and safety, and emissions have become mandatory in certain specific area of applications. It has been recognized for many years that vegetable oils (VO) can be used as fuel and lubricants. The use of VO as fuel has been demonstrated in 1900 at the Paris exposition, where a diesel engine was run wholly on ground-nut oil. Vegetable oils are already in use as lubricants due to their superior lubricity, good anticorrosion, better viscosity-temperature characteristics and low evaporation loss in industrial applications such as rolling, cutting, drawing and quenching operations either alone or in combination with mineral oils. Moreover, these oils are readily biodegradable and environmentally safe compared to mineral oil as it contains readily biodegradable constituents such as fatty acids. Using the EPA Shake Flask test, soybean oil degrades within 7 days, while mineral oil takes 28 days. Some other advantages of VO based lubricants include their naturally renewable resource and no dependence on foreign oils. From the environmental point of view their importance is evident especially in areas of total loss lubrication, military applications, and in outdoor activities such as forestry, mining, railroads, dredging, fishing and agriculture hydraulic systems. However, extensive VO use is restricted due to poor cold flow behavior, low thermo-oxidative and hydrolytic stability, which can be mitigated by suitable modifications of the oil structure. Recent environmental awareness has shifted the world attention towards the application of VOs as biodegradable lubricants.