Some alternatives to standard motor oil are available.
Every motor vehicle requires some sort of lubricating oil to assure that its components slide and rotate together without causing damage to themselves or the engine’s other parts. Usually, lubricating oil is made from petroleum products, but in recent years a push has occurred toward finding alternatives that are renewable and kinder to the environment. Although the vast majority of motor oils are still petroleum-based, a few alternative lubricating oils do exist.
Poly Alpha Olefins
Poly alpha olefins (PAOs) were discovered while attempting to derive fuel from oil shale or waste fuel. They provided an excellent base for lubricating oils. These oils had a better heat transfer capability than mineral-based oil, as well as a much larger temperature range. During the 1970s, PAOs were seen as a viable possibility, but a couple major synthetic brands proved to have bad side effects and PAO-based oils were all but abandoned. However, in recent years these lubricants have come back into wide use, and are the most common type of synthetic lubricant.
Poly-ol ester lubricants first came into wide use in the aircraft industry. These engine lubricants are plastic-based, and are strong and durable, able to stay inside of an engine for its entire working life. These lubricants also have excellent heat transfer properties and a large temperature range. However, poly-ol ester oils are also expensive. They are primarily used in racing.
Canola-Based Motor Oils
Canola oil-based lubricants have shown a great deal of promise as a possible competitor to synthetic motor oils. In tests, they have shown themselves to have a high resistance to pressure in relation to synthetic oils, as well as allowing less friction and a 5 percent increase in fuel economy. Canola-based motor oils also price very competitively with other types of motor oils.
High Oleic Sunflower Oil
High oleic sunflower oil is another “biolube,” that is, biological lubricator, that has shown a great deal of promise in tests. Sunflower oil does not quite match the performance of synthetic oils, but studies done in the 1990s showed the sunflower approaching their performance, and outperforming mineral-based oils in emissions, fuel economy and engine wear. Sunflower oils had the best results when mixed with another type of oil called ester oil. Ester oils come from reactions between alcohols, acids and water.
Re-Refined Lubricating Oils
Re-refined lubricating oils are still mineral-based, but are recycled from already-used motor oils. In addition to simply removing impurities, the process of re-refining used motor oil also involves the removal of chemical impurities. Re-refined oil can perform just as well as virgin oil, and sometimes even better.