hüdrodesulfuratsioon

Hydrodesulfurization, often abbreviated as HDS, is a common chemical process used in petroleum refineries. Its primary purpose is to remove sulfur compounds from various petroleum fractions, such as naphtha, kerosene, diesel fuel, and gas oils. Sulfur is an undesirable element in fuels because its combustion produces sulfur dioxide (SO2), a major air pollutant contributing to acid rain and respiratory problems. Additionally, sulfur compounds can poison catalysts used in downstream refining processes and reduce the quality of the final fuel products.

The HDS process typically involves reacting the sulfur-containing feedstock with hydrogen gas at elevated temperatures and pressures in the presence of a catalyst. Common catalysts include transition metal sulfides, such as molybdenum disulfide (MoS2) or tungsten disulfide (WS2), often supported on alumina (Al2O3). During the reaction, the sulfur atoms in the organic molecules are converted into hydrogen sulfide (H2S). This H2S is then separated from the desulfurized hydrocarbon stream. The H2S is subsequently treated in other refinery units, most commonly in a Claus process, to recover elemental sulfur, which can then be sold or used elsewhere.

The severity of the HDS process, including temperature, pressure, hydrogen partial pressure, and catalyst type, is adjusted based on the specific feedstock and the desired level of sulfur removal. Modern environmental regulations often require very low sulfur content in transportation fuels, necessitating highly efficient HDS operations. HDS is a critical step in producing cleaner fuels and minimizing the environmental impact of petroleum products.