production of wax esters in crambe

• Tackiness agents – For applications where the oil needs to adhere to the
surface extremely well. Examples are polymers of e.g. aluminium soaps
of long-chain fatty acids.
• Antiwear agents (AW) – AW agents are polar molecules that bind or
attach themselves to metal surfaces. In this way they form a layer that
protects the metal surface from wear that can occur during boundary
lubrication conditions e.g. direct contact between asperities. This reduces
friction and wear up to 250°C. Anti-wear improvements can be achieved
from adding sulphurised fatty acids to the base oil (Cao et al., 2000).
• Detergents and dispersant – Are added to a lubricant to keep compounds
and substances dissolved in the liquid and avoiding a deposition onto
metal surfaces.
• Compounded oil – A mineral oil that is blended with animal or vegetable
oil in order to improve its performance as a lubricant.
2.5.2 Performance-Enhancing additives
• Pour-point depressants – The temperature where an oil does not pour or
flow any more is referred to as the pour point. Molecules such as paraffin
waxes tend to solidify and stiffen at low temperatures. Pour point
depressants reduce the size and cohesiveness of these crystal
structures, which reduces the pour point of the base oil and increases
flow at lower temperatures.
• Viscosity index (VI) improvers – VI improvers are used to limit the rate of
change of viscosity with temperature. Their effects are generally
observed at higher temperatures where they allow the viscosity of the oil
to increase within a limited range permitted by the oils and the
concentration of the additive.
• Emulsifiers – Soluble oil requires that water can be emulsified rapidly and
form stable emulsions. Emulsifiers are used in lubricants used for cutting,
grinding, and drilling applications in machine shops.
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