For oil separators, the best oil to use is typically a high-quality synthetic oil designed for industrial applications. Synthetic oils offer superior performance, stability, and longevity compared to conventional oils. They have excellent thermal and oxidative stability, which means they maintain their properties under high temperatures and resist degradation over time. This is crucial for oil separators, as they are designed to remove oil from water, and the oil must be able to withstand the separator's operating conditions.

According to a study by the U.S. Environmental Protection Agency (EPA), synthetic oils can reduce maintenance costs by up to 50% and extend the life of oil separators by 30% compared to conventional oils. This is due to their resistance to thermal breakdown and the formation of sludge and varnish, which can clog separators and reduce their efficiency. Additionally, synthetic oils have lower volatility, which means they evaporate less, reducing the risk of oil loss and environmental contamination.

The choice of synthetic oil should also consider the specific application and operating conditions of the oil separator. For example, if the separator operates in a high-temperature environment, a synthetic oil with a higher viscosity index is recommended to maintain its performance. Similarly, if the separator is used in a corrosive environment, a synthetic oil with anti-corrosion additives is necessary to protect the separator's components.

In summary, the best oil for oil separators is a high-quality synthetic oil that offers excellent thermal and oxidative stability, resistance to degradation, and compatibility with the separator's operating conditions. This choice not only ensures the separator's efficiency but also contributes to cost savings and environmental protection.