Kinetics study of H-atom abstraction from 3-pentanone by Ḣ and ĊH3 radicals and the subsequent isomerization reactions. (15th January 2019)

• Record Type: Journal Article
• Authors: Cheng, Jia; Zou, Chun; Liu, Yang; Liu, Shibo; Jia, Huiqiao; You, Xiaoqing
• Is Part Of: Fuel. Volume 236(2019)
• Page Start: 1018
• Page End: 1025
• Publication Date: 2019-01-15
• Subjects: 3-Pentanone -- Kinetic -- H-atom abstraction reaction -- Isomerization reaction -- MS-T; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2018.09.011
• Languages: English
• ISSNs: 0016-2361

Abstract

Abstract: 3-Pentanone has been recently identified as a promising biofuel candidate. H-atom abstraction from 3-pentanone by H ̇ and C ̇ H 3 radicals and the subsequent isomerization reactions are important in chemical mechanism of 3-pentanone. In the present study, the potential energy surfaces were calculated at M06-2X/ma-TZVP//M06-2X/6-311+G(2df, 2p). The rate constants of these reactions were calculated using the conventional transition state theory (TST) including the multi-structural torsional (MS-T) anharmonicity and tunneling corrections with the Eckart approximation. The results show that the updated rate constants deviate from previous data by up to a few orders of magnitude. Tunneling effect increases the rate constants at low temperatures significantly. Torsional anharmonicity was taken into consideration by the MS-T method. Hydrogen from the methylene in 3-pentanone is easier to be abstracted than from the methyl group. Hydrogen abstraction by H ̇ from the methylene in 3-pentanone is the fastest reaction among them. The calculated rate constants of the five reactions are updated in the Dames-2014 mechanism, and the predictions of ignition delay time of the updated mechanism agree better with the previous experimental data.