Synthetic Oil - Advantages & Disadvantages

A synthetic oil is an oil manufactured for enhanced lubrication performance using the Fischer-Tropsch process which converts carbon dioxide, carbon monoxide, and methane into liquid hydrocarbons of various forms. The carbon dioxide and carbon monoxide is generated by partial oxidation of coal and wood-based fuels. This process was developed and used extensively in World War II by Germany, which had limited access to crude oil supplies. Germany's yearly synthetic oil production reached more than 90 million tons in 1944. It is today used in South Africa to produce most of that country's diesel from coal. There are several companies developing the process to enable practical exploitation of so-called stranded gas reserves, those reserves which are impractical to exploit with conventional gas pipelines and LNG technology..

The majority of oil lubricants are mineral oils, mixtures of refined fractions of crude oil.

Synthetic oils are fabricated by polymerizing short chain hydrocarbon molecules into longer single chain hydrocarbons. Their lubrication characteristics can be adjusted by controlling the spectrum molecular weights that go into the finished formulation, which usually also includes thickeners.

Synthetic Oil first became commercially available in the mid 1970's. The first company to make synthetic oil available in the United States was Amsoil Inc.

Advantages

Manufacturers claim the following benefits for synthetic oils:

Improved viscosity at low temperatures. Mineral oils tend to include wax impurities which coagulate at lower temperatures. A typical 10W-30 oil remains liquid at -50 °C (-58 °F)
* Better high temperature performance. Synthetic oils have few low molecular weight hydrocarbons which evaporate at high temperatures.
* Higher purity
* Decreased oil consumption
* Reduced friction and engine wear
* Improved fuel consumption through better engine lubrication
* Longer intervals between oil changes
* Resistance to oil sludge problems
* Crude oil doesn't have to be used for the production of the lubricants

Disadvantages

The primary disadvantage of synthetic oils is that they cost significantly more than mineral oils. The manufacturers of synthetic oils argue that this is offset by an extended working life. As synthetic oils tend to be more fluid they are also more prone to leak through worn seals.

Many argue that the advantages of synthetic oils are only significant in high performance applications such as motor racing and aviation, road haulage, or for general lubrication in extreme environments.

Semi-Synthetic oil

A semi-synthetic oil is a blend of mineral oil with a small percentage of synthetic oil. They are designed to provide many of the benefits of synthetic oil without increasing the cost too much.