Importance of Hydrotreating in Petroleum Refining

In the first step of petroleum refining, crude oil is fed to the atmospheric fractionation tower to obtain straight-run distillates such as naphtha, kerosene, and gas oil. Such raw products cannot be used directly as transportation fuels due to several technical limitations such as high amounts of impurities (sulfur, nitrogen, and aromatics) and low octane and cetane numbers in the cases of gasoline and diesel fuels, respectively. These streams 

FIGURE 7.1 Importance of hydrotreating in a typical petroleum refinery. 

HDT process has gained significant relevance in the industry due to the growing demand for transportation fuels and the strict environmental legislations. Its major applications in current refinery operations (downstream sector) and petroleum production (upstream sector) can be grouped into the following categories  

Feed pretreatment for conversion processes such as isomerization, catalytic reforming, catalytic cracking, and HDC, aiming at reducing the amount of sulfur, nitrogen (particularly basic nitrogen), metals, and polynuclear 

Upgrading of heavy crude oils. This is a relatively recent application of HDT, in which the heavy petroleum is directly hydrotreated to  

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