Hydroprocessing is a critical process used in the petroleum refining industry to remove impurities from crude oil and other feedstocks. It involves the use of hydrogen gas in the presence of a catalyst to remove sulfur, nitrogen, and other unwanted contaminants from the feedstock, resulting in cleaner and more valuable products. The two most common types of hydroprocessing are hydrocracking and hydrotreating. Hydrocracking is used to break down heavy, high-boiling feedstocks into lighter, more valuable products like gasoline and diesel fuel. Hydrotreating, on the other hand, is used to remove sulfur, nitrogen, and other impurities from lighter feedstocks like naphtha and diesel fuel. Hydroprocessing is a complex process that requires careful control of temperature, pressure, and catalyst activity. The process typically takes place in a reactor vessel, where the feedstock is mixed with hydrogen gas and passed over a bed of catalyst. The catalyst helps to facilitate the chemical reactions that remove impurities from the feedstock.