hydrokrakování

Hydrokrakování is a catalytic chemical process used primarily in the petroleum industry to convert heavier hydrocarbon fractions into lighter, more valuable products. The term combines "hydrogenation" and "cracking," referring to the simultaneous addition of hydrogen (hydrogenation) and breaking of larger hydrocarbon molecules into smaller ones (cracking). This process is essential for upgrading residual oils, vacuum gas oils, and other heavy feedstocks into diesel, jet fuel, and other middle distillates.

The reaction typically occurs at high temperatures (350–450 °C) and pressures (50–200 bar) in the presence of a catalyst, often a mixture of metals such as molybdenum, nickel, or cobalt supported on alumina or silica. Hydrogen gas is supplied to saturate aromatic compounds and stabilize the resulting products, improving their stability and reducing sulfur, nitrogen, and metal content. Unlike catalytic cracking, hydrokrakování does not rely on acid catalysts but instead uses hydrogen to prevent coke formation and extend catalyst lifespan.

Hydrokrakování is particularly advantageous for producing high-quality diesel fuels with low sulfur and aromatic content, meeting stringent environmental regulations. It is also employed in the production of lubricating oils and petrochemical feedstocks. The process is energy-intensive but highly efficient for converting low-value heavy residues into more profitable products, making it a key technology in modern refinery operations. Variations of hydrokrakování, such as hydrocracking with zeolite catalysts, further enhance selectivity and yield for specific applications.