Plant‐oil‐based lubricants and hydraulic fluids

Abstract

It is estimated that, at present, approximately 50% of all lubricants sold worldwide end up in the environment via total loss applications, volatility, spills or accidents. More than 95% of these materials are currently mineral oil based. In view of their high ecotoxicity and low biodegradability, mineral oil-based lubricants constitute a considerable threat to the environment. In contrast, most lubricants and hydraulic fluids based on plant oils are rapidly and completely biodegradable and are of low ecotoxicity; moreover, lubricants based on plant oils display excellent tribological properties and generally have very high viscosity indices and flashpoints. However, in order to compete with mineral-oil-based products, some of their inherent disadvantages must be corrected, such as their sensitivity to hydrolysis and oxidative attack, and their behaviour at low temperatures. Various methods to improve the undesirable properties of native plant oils will be discussed. In parallel, government regulations that encourage or enforce the use of bio-based fluids, at least in ecologically sensitive areas, will help to increase their market share. Using the numerous possibilities for selective breeding and/or chemical improvement of the double bond systems of natural fatty acids by increased R&D, the major obstacles regarding the use of plant-based raw materials for the production of lubricant base fluids can be overcome and bio-based fluids should expect a future with increasing market shares.

Human Health Concenrs of Metalworking Fluid Components

“…If these materials escape to the environment, the impacts tend to be cumulative and consequently harmful to plant, fish, and wildlife (15). Mineral oils are toxic for mammals, fish and bacteria (16). As an alternative to mineral based lubricants, several major categories of synthetic lubricants are available, including synthesized hydrocarbons; synthetic esters; phosphate esters; polyglycols; and silicones.…”

A Novel Methodology for the Synthesis of Acyloxy Castor Polyol Esters: Low Pour Point Lubricant Base Stocks

“…80W-140, bearing lubricants and positive displacement blowers, forging lubricants and metal working fluids 13 . 24,36 . However, viscosity index values were more than most of the reported acylated derivatives 13,17,22 .…”

High‐value oils from plants

“…They therefore currently capture only a narrow segment of the total lubricants market (Whitby, 2004). The low oxidative stability of vegetable oils can be improved through chemical modification of plant oils or by using speciality oils, such as castor bean oil (Ricinus communis), for high-temperature applications (Schneider, 2006). Despite a widespread demand for castor oil, however, cultivation of this crop is restricted due to the presence of a toxin (ricin) and allergenic proteins, and thus the cost of castor oil is relatively high.…”