With time and distance travelled, passenger car motor oils (PCMOs) become dirty but the underlying base oils do not wear out. In fact, it is the additives package (i.e., dispersants, detergents, antioxidants, etc.) in the PCMO that breaks down, while additional contaminants (i.e., metal filings, etc.) are introduced from the engine. To maintain maximum engine efficiency, PCMOs need to be changed on a regular basis. The re-refining process is able to remove the spent additives and contaminants and return the base oil to its original state for blending into new PCMO formulations.

An estimated 2.4 billion gallons of motor and industrial lubricants are sold in the United States each year, generating 1.36 billion gallons of UMO available for collection and recycling. Of this, 72% is collected, leaving the possibility that 380 million gallons of uncollected oil makes its way into the environment. Of the ~980 million gallons collected, over 400 million gallons per year is processed into industrial fuels, resulting in nearly 800 million gallons per year, or 58%, of all UMO generated being burned or dumped.(1) In addition to the environmental impacts of this practice, this represents the lowest value end use for used motor oil. Re-refining produces high-quality end products that are indistinguishable from virgin crude products, while diverting a harmful waste stream and contributing to resource sustainability.

History of Re-refining

Oil re-refining has been around for decades, but it was the OPEC oil embargo in the 1970s that forced innovation in the sector. Before this time oil recycling technologies were not able to produce base oils that met the market’s quality standards. However, a tripling of crude prices incentivized technological development to meet the demand.

In the 1980’s hydrotreating was introduced to the industry in the form of the Phillips Re-refined Oil Process. This first commercial scale re-refining technology demonstrated the viability of hydrotreating and was used by other companies in their emerging used oil management facilities. As more companies entered the market they began to improve on the technology, incorporating another refining technology called vacuum distillation and making further process improvements, resulting in a process that became industry standard for three decades.

From 1991-2008 there were no new re-refining projects in North America. However, the oil boom following this period, combined with a shift towards higher-quality lubricants has caused the industry to innovate once again, and ReGen III is leading the way with its breakthrough ReGen™ re-refining technology.

ReGen™ Technology

ReGen™ combines proven refining technologies into a proprietary process that is able to extract a higher quantity of high-quality base lubricating oils than traditional re-refineries, including approximately 53% Group III base oil production.

Used motor oil will arrive at the ReGen III facility where it will go through a series of refining processes to remove contaminants and restore the base oils to their original state. As the UMOs are processed, the highest-quality base oils are separated from other petroleum by-products, such as ultra-low sulphur diesel.

The end result is Group III and Group II base oils that meet the American Petroleum Institute’s standards. These base stocks will be sold to lubricant producers to be mixed with additives packages to create high-quality finished PCMOs.


(1) Used Oil Management and beneficial Reuse Options to Address Section 1: Energy Savings from Lubricating Oil Public Law 115-345” (available at 2022 value based on 2008 – 2018 growth rates and data, extrapolated from 2018.