Oilers/Plant Tenders (HHC) Civil Service Exam 2026 – 400 Free Practice Questions to Pass the Exam

Demulsibility of oil refers to its ability to separate from an emulsion, which is a mixture of two liquids that are typically not soluble in each other, such as water and oil. When oil has good demulsibility, it means that it can effectively break away from water or other impurities present in an emulsion. This property is essential in various applications, particularly in lubrication and hydraulic systems, where the presence of water can lead to decreased system efficiency and potential damage.

Enhanced lubrication efficiency, reduction of engine wear, and improvement of oil viscosity are important characteristics of lubricants but do not directly relate to the concept of demulsibility. While these factors can contribute to the overall performance of oil, they do not address the specific ability of the oil to separate from emulsified water or other substances. Therefore, the correct focus on the ability to separate from an emulsion clarifies why this answer is accurate in the context of demulsibility.