hydrodesulfurization

Hydrodesulfurization is a process used in oil refineries to remove sulfur from petroleum products like crude oil and natural gas. This is done to make the products more efficient and to reduce harmful emissions when they are burned.1

The process involves mixing the sulfur-containing oil with hydrogen and a catalyst, typically cobalt and molybdenum oxides on an alumina base. This mixture is heated to high temperatures (260–425 °C) and pressures (14–70 bars). The sulfur is converted into hydrogen sulfide, and nitrogen impurities are converted into ammonia. The hydrogen sulfide is then removed and can be used to produce pure sulfur, while the ammonia can be processed into fertilizers.12