Liquid Lubricants: Synthetic Oils and Lanolin

Liquid lubricants are fluids that prevent friction and wear between two machine parts. Common liquid lubricants include water-based lubricants and synthetic oils. Many liquid lubricants can pollute the environment, so proper disposal of used lubricant is essential.
 

Liquid Lubricant Uses

Liquid lubricants reduce friction between two moving objects by creating a smooth, wet layer between the two solid surfaces. The protective coating the lubricant offers also reduces the wear and tear that would occur if both objects interacted without lubrication.
 
Another unique feature of liquid lubricants is that they effectively cool hot surfaces. To do so, the lubricant must flow from the hot area of the machine into a cooler area and then back through the hot area. This flow allows the lubricant to continually cool parts as generate heat through movement.
 
Finally, liquid lubricants often contain detergents and other substances that remove debris and dirt from machine parts. A common example is motor oil, which carries engine debris to the oil filter where debris is removed from the oil.
 
Liquid lubricants are the best lubrication choice when the lubricant must flow through machinery. Not only will theses type of lubricants easily flow through a machine, but they also serve as more effective cooling agents than solid lubricants.

Water-Based Lubricants

Water-based lubricants fulfill a number of roles, including applications in metal cutting and grinding. While the simplest water-based lubricant is water itself, more complex, commercial water-based lubricants usually consist of water mixed with some type of base oil.
 
Water-based lubricants are also used as personal lubricants. Because oil-based lubricants can erode latex, water-based lubricants are better choices for safely using condoms.
 

Mineral Oils
Mineral oils are usually made from crude petroleum, which can be processed to create fluids with varying viscosity. Mineral oils are some of the most common liquids used in machinery.

Synthetic Oils

Synthetic oils are man-made lubricants that have greater operating ranges than mineral oil lubricants. AS a result, synthetic oils are better choices than mineral oils in certain circumstances.
 
Esters, silicone fluid and flurocarbons are examples of synthetic oils. Silahydrocarbons are synthetic oils composed, as the name suggested, from hydrogen, silicon and carbon. Silahydrocarbons have the potential to provide fluidity and lubrication in space machinery.

Vegetable-Based Liquid Lubricants

Liquid lubricants can also be manufactured from plant life. Sources of vegetable-based lubricants include:
  • canola
  • palm oil
  • rapeseed
  • sunflower seed.

While more environmentally friendly than mineral and synthetic oils, vegetable-based liquid lubricants are rarely used in vehicles or machinery.

Lanolin
Lanolin is one of the few liquid lubricants manufactured from animal matter. Lanolin is derived from wool grease, a naturally water repellant substance present on sheep's wool.
 
Lanolin is a naturally occurring, renewable resource that can be harvested every time a sheep is sheared. Consequently, it is non-toxic, making it an ecologically friendly alternative to mineral and synthetic oils. As well as reducing friction and wear, lanolin liquid lubricants have anticorrosive properties.

Additives and Liquid Lubricants

Many liquid lubricants contain additives. Examples of lubricant additives include:
  • anti-foaming agents
  • antioxidants
  • anti-wear agents
  • corrosion inhibitors
  • demulsifying agents
  • emulsifying agents
  • rust inhibitors
  • viscosity improvers.
On average, liquid lubricants that contain additives are 90 percent base oil and 10 percent additives. Keep in mind that, because many liquid lubricant additives are toxic or carcinogenic, it's advisable to avoid direct contact with the lubricant whenever possible.

Disposing of Liquid Lubricants

Liquid lubricants must be disposed of safely and correctly. Mineral and synthetic oils can contaminate water supplies, resulting in environmental damage and potential health problems. Only a small amount of liquid lubricant is necessary to contaminate a large supply of water.
 
Used liquid lubricants can be recycled or burned as a fuel source. Burning liquid lubricants is heavily regulated and requires specially built facilities to prevent air pollution. Burning liquid lubricants at home is never recommended: Not only is it illegal in most areas, the resulting smoke is often toxic and can cause serious medical emergencies.
 
Recycling liquid lubricants has become increasingly popular, although not every locale has the recycling technology necessary for this option. When available, however, recycling is one of the most effective ways of preventing liquid lubricants from entering the environment.

Tips for Liquid Lubricant Disposal

Up to 40 percent of all lubricants, liquid or otherwise, eventually end up in the environment. While some of this pollution stems from businesses, a large percent of lubricants are introduced into the environment by individuals. If you are disposing of liquid lubricants, please consult the following suggestions:
  • Do not pour liquid lubricants down the drain.
  • Don't throw lubricants into the trash or landfill.
  • Never burn or bury liquid lubricants.
  • Seal the lubricant in a tightly closed container.
  • Transport the lubricant to a collection location or recycling facility.
Resources
 
Answers.com. (n.d.). Lubricant. Retrieved January 28, 2008, from the Answers.com Web site: www.answers.com/topic/lubricant.

Mobil Oil. (2005). FAQs for Synthetic Oils. Retrieved January 28, 2008, from the Mobil Oil Web site: www.mobiloil.com/USA-English/MotorOil/Synthetics/Synthetic_Oils_FAQs.aspx.

Nye. (n.d.). New Liquid Lubricants Show Promise for Space Mechanisms. Retrieved January 28, 2008, from the Nye Web site: www.nyelubricants.com/2001_010.htm.