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In the initiation step, a hydrocarbon (RH) reacts with oxygen (O2) to make a hydrocarbon
radical (Râ˘), which reacts with oxygen to make a peroxy radical (RO2â˘). (Radical species are
denoted by the ââ˘â symbol next to the character.) Next, an internal hydrogen-atom abstrac-
tion takes place (i.e. the abstraction of a hydrogen atom from the molecule itself). Following
the internal abstraction, the radical â˘Râ˛OOH reacts internally to eliminate (eject) OH and
forms a compound without free valences (unpaired electrons) such as an aldehyde or ketone
(Reaction (4)). The mechanism continues with a second O2 addition to the peroxy radical
initially formed (Reaction (5); [23]). After a few steps, keto-hydroperoxide (HO2RâO) is
formed (Reaction (10)). Keto-hydroperoxide decomposes at around 800 K, producing further
hydroxyl (OHâ˘) that consumes the fuel (Reaction (11)). In the hydrogen abstraction reac-
tion (Reaction (3)), the molecule isomerizes by âreaching aroundâ and abstracting a hydrogen
Figure 4. An example of HCCI combustion for (a) overall heat-release rate, (b) magnified view of heat-release rate, (c)
in-cylinder temperature and (d) mole fraction.
Advanced Chemical
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book Advanced Chemical Kinetics"
Advanced Chemical Kinetics
- Title
- Advanced Chemical Kinetics
- Author
- Muhammad Akhyar Farrukh
- Editor
- InTech
- Location
- Rijeka
- Date
- 2018
- Language
- English
- License
- CC BY 4.0
- ISBN
- 978-953-51-3816-7
- Size
- 18.0 x 26.0 cm
- Pages
- 226
- Keywords
- Engineering and Technology, Chemistry, Physical Chemistry, Chemical Kinetics
- Categories
- Naturwissenschaften Chemie