ABSTRACT
Turbine oils are required to have good oxidation stability. The importance of the low temperature properties of industrial oils is dependent on their intended use. The literature reports that there is no need for low pour points of oils to be used inside heated plants or in a continuous service, such as steam turbine (Bock, 2001). Turbine oils are also required to have good interfacial properties, such as resistance to foaming, good air separation properties, good demulsibility, and good rust-and corrosion-preventive properties. High quality turbine oils are formulated from highly refined paraffinic base stocks and have high viscosity-temperature characteristics. Gas turbines for industrial applications require high temperature-operating conditions, and, for particularly high temperature, the use of synthetic base stocks is required (Kajdas, 1997). The early literature reports on the oxidation stabilities of solvent-refined and clay-finished paraffinic base stocks, and the hydrotreated oil used to formulate turbine oils (Beuther, Donaldson, and Henke, 1964). According to the literature, the term “hydrotreated” mineral base stock refers to the removal of undesired components, such as condensed aromatics and polar compounds, by passing the oil over a catalyst in the presence of hydrogen at a temperature ranging between 50°C and 500°C and a pressure ranging between 200 and 4000 psi (Butler and Henderson, 1990).
