In-depth analysis: The coking mechanism in ethylene cracking! ! !
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Please discuss the mechanism of radical coking! ! Or there might be other mechanisms! ! ! Everyone is welcome to discuss
It is generally believed that there are three mechanisms for coking in furnace tubes: metal-catalyzed coking, free-radical uncatalyzed coking, and tar uncatalyzed coking. In the early stages of operation of the pyrolysis furnace, metal-catalyzed coking on the inner surface of the furnace tubes is the dominant factor, resulting in the formation of a dense layer of coke on that inner surface. Thereafter, the heavy aromatic hydrocarbons attached to the coke are dehydrogenated by free radicals to form carbon, while tar particles formed in the gas phase adhere to the tube wall as coking.
Coking generally occurs in three stages: first, surface coking takes place at the beginning; then, operation continues at a steady pace while maintaining the initial state of coking; and after another period, deposition-based coking begins.
Three, namely through acetylene coking, aromatic polycondensation coking, and catalytic coking mechanisms.
Catalytic coking? Where exactly?