Fluid catalytic cracking in the context of "Carbon black"

Marine diesel oil (MDO) is a type of distillate diesel oil. Marine diesel oil is also called distillate marine diesel. MDO is widely used as motor fuel by medium speed and medium/high speed marine diesel engines. It is also used in the larger low speed and medium speed propulsion engine which normally burn residual fuel. Those fuels result from a catalytic cracking and visbreaking refinery. Marine diesel oil has been condemned for its high sulfur content, so many countries and organizations established regulations and laws on MDO use. Due to its lower price compared to more refined fuel, MDO is favored particularly by the shipping industry.

Butene, also known as butylene, is an alkene with the formula C₄H₈. The word butene may refer to any of the individual compounds. They are colourless gases that are present in crude oil as a minor constituent in quantities that are too small for viable extraction. Butene is therefore obtained by catalytic cracking of long-chain hydrocarbons left during refining of crude oil. Cracking produces a mixture of products, and the butene is extracted from this mixture by fractional distillation.

Butene can be used as the monomer for polybutene, but this polymer is more expensive than alternatives with shorter carbon chains such as polypropylene. Polybutene is therefore used in more specialized applications. Butenes are more commonly used to make copolymer (mixed with another monomer such as ethylene).