Theoretical Study Of The Hydrogen Abstraction Reactions Kinetics From Substituted Phenolic Fuels And Thermodynamic Properties Of Halogenated Aromatic Hydrocarbon

Currently,about 85%of the world’s energy demand comes from combustion,and it is widely used in engineering and life.Although solar energy and biomass energy are gradually being developed and utilized as new energy sources,fuel combustion will still be the world’s main source of energy for a long time to come.The study of the chemical reaction mechanism of various fuel combustion is of great significance to the combustion chamber,pollutant control and the research of alternative fuels.The chemical reaction mechanism of fuel combustion is composed of elementary reactions and kinetic parameters（i.e.,rate constants）,thermodynamics parameters of a substance（such as entropy,enthalpy）and transport coefficients involved in combustion.The accuracy of the kinetic simulation based on the combustion reaction mechanism depends on the rationality of the reaction mechanism and the accuracy of the kinetics,thermodynamics and transport coefficients.The detailed combustion reaction mechanism of macromolecular fuel usually includes hundreds of components and thousands of elementary reactions.It is unrealistic to carry out precise experimental measurement of the kinetics of all elementary reactions and the thermodynamics of substances included in the detailed combustion reaction mechanism,theoretical computational chemistry has become the main source of the thermodynamics and kinetic parameters of the combustion reaction mechanism.Based on this,this work uses computational chemistry methods to study the hydrogen abstraction reactions kinetics from substituted phenolic fuels and thermodynamic properties of halogenated aromatic hydrocarbon,which consists of five chapters.Chapter One:Introduction.The background and significance of this research,the research status of the hydrogen abstraction reactions kinetics from substituted phenolic species and thermodynamic properties of halogenated polycyclic aromatic hydrocarbon are introduced in this chapter.Chapter Two:Basic theory and methods.This chapter mainly introduces the theories and methods related to the subject,including ab initio calculation,composite method,density functional theory,basis set,intrinsic reaction coordinates,transition state theory,tunneling correction,etc.Chapter Three:In this chapter,the hydrogen abstraction reactions kinetic properties by H/CH₃/O（³P）/OH/HO₂ radicals on anisole,o-guaiacol,m-guaiacol,p-guaiacol and phenol were calculated.The abstraction reactions by H/CH₃/O（³P）radicals exhibit similar reaction trend.The abstraction reactions by H radical,the rate constants on the OCH₃ group in anisole and on the OH group in phenol are large than that on the aromatic ring,the rate constants on the OCH₃ group in anisole are large than that on the OH group in phenol.For the three isomers of guaiacol,the rate constants on OCH₃ and OH groups are both lower than that in anisole and phenol.OH/HO₂ radicals show different trends due to the influence of the formed van der waals complexes.Chapter Four:Using CBS/QB3,G3MP2,G3,G4 combination method and 9 kinds of density functional method to caculation the single point of the structure and the atoms,then get the bond dissociation enthalpy of the halogenated aromatic hydrocarbons,the formation enthalpy of halogenated aromatic hydrocarbons by atomization method to obtained,and the caculated bond dissociation of enthalpy and formation enthalpy were compared with the existing experimental values,the results show that the minimum absolute average errors of bond dissociation enthalpy calculated by M06-2X/6-311++g（d,p）method is 1.61 kcal/mol,the minimum absolute average errors of the enthalpy of formation calculated byωB97XD/cc-p VTZ method is 6.97 kcal/mol.And analyzed the two methods get the bond dissociation of enthalpy and formation enthalpy,the results show that the bond dissociation enthalpy of chlorinated aromatic hydrocarbons is greater than the brominated aromatic hydrocarbons,and the enthalpy of formation of chlorinated aromatic hydrocarbons is less than the brominated aromatic hydrocarbons,except for 4-halogenated phenanthrene,1-halogenated acenaphthylene,9-halogenated fluorene,1-halogenated acenaphthene,the position of the halogen atom and the number and type of the ring have little effect on the bond dissociation enthalpy.Except for 4-halogenated phenanthrene,the halogen atom of different positions of the same structure has little effect on the enthalpy of formation.But the number and type of rings have a greater influence on the enthalpy of formation.Chapter Five:This chapter mainly introduces the conclusions and prospects of this research.