Hydrotreating is a chemical process used in the oil refining industry to improve the quality of petroleum products. It involves treating crude oil fractions with hydrogen gas in the presence of a catalyst. This process helps remove impurities such as sulfur, nitrogen, and metals, which can negatively affect fuel quality and emissions. The main goal of hydrotreating is to produce cleaner fuels, such as diesel and jet fuel, that meet environmental regulations. By reducing harmful components, hydrotreating enhances the performance and stability of fuels, making them safer for both engines and the environment.