Cracking is a widely used chemical method of processing crude oil. The process emerged as a consequence of increased gasoline demand and increased the yield of gasoline fractions of oil to 50-60%. Cracking can be applied not only to crude oil, but also to its distillate fractions.
There are thermal and catalytic cracking processes. In the former case, the process occurs at high temperature, in the latter case it requires a catalyst. The efficiency of cracking is also influenced by pressure and duration.
Catalytic cracking is considered more efficient than thermal. This is due to the transformation of some unsaturated hydrocarbons to saturated, which improves the quality of the product. The method also has drawbacks, such as the quick exhaustion of catalyst, which must be quickly regenerated to restore its performance.
There is a method of ebullated bed cracking. It differs in the design of the reactor, which is combined with a regeneration unit. There are also designes with moving catalyst and circulation of catalyst between the reactor and the regenerator.