Formation during gasoline production

The combustion of gasoline air mixtures in the combustion chamber of spark ignited engines leads essentially to the fonnation of total oxidation products, but also to CO, H2, NO, a hydrocarbon (HC) mixture and SO2. Several HC emissions formation mechanisms are possible to explain the origin of tlie hydrocarbon mixture [1,2], such as flame quenching at tlie cylinder walls or at crevice entrance, adsorption-desorption in the oil film and incomplete combustion (partial or complete misfire) particularly during transient operations. The HC that are not combusted (about 1 % of the gasoline) are either exliausted unmodified or... 

The discovery of conjunct polymerization, whereby hydrogen transfer occurs between molecules of olefins, leading to the formation of saturated hydrocarbons and polyenes, became the forerunner of the discovery of alkylation and isomerization of paraffins. During World War II these processes were used for the manufacture of high octane aviation gasoline to be used in pursuit planes, and presently products from the alkylation reaction assumed new importance as a major component of unleaded gasoline (Figure 4). 

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