Hydrotreating

Hydrotreating is the process of removal of organic sulfur, nitrogen, oxygen and metals from petroleum crude at high hydrogen pressure. This process is also used for hydrogenation of unsaturates. Examples of sulfur, nitrogen and metal containing compounds as found in pertoleum crude are shown in Fig 4. Importance of hydrotreating is increasing due to decrease in availability of light and sweet crudes. Heavier crudes contain more sulfur, nitrogen and metal compounds requiring increasing treatment for removal of these compounds which act as poison for downstream processes. More and more stringent emission standard for sulfur and nitrogen content in fuels is another reason for higher interest in hydrotreating processes.

Fig. 4. Examples of sulfur, nitrogen and metal containing compounds in petroleum crude