Study on reaction mechanism and kinetics of NO and SH radical
In order to explore the influence of interaction between nitrogen and sulfur components on the evolu-tion of sulfur components in the operation of coal-fired power generation units during deep peak shaving,the detailed reaction mechanism of NO and SH radical was studied.B3LYP/6-311++G(d,p)method was used to optimize the geometry of all stationary species on the reaction path between SH radical and NO,and IRC verified the correctness of the reaction path.At the CCSD(T)/def2-TZVPP level,the energy of each stationary point on the reaction path was calculated,and the potential energy surfaces of the reaction in the singlet state and trip-let state were obtained by frequency correction and zero-point energy correction.The calculation results show that there are eight reaction paths and three possible products,respectively P1(SN+OH),P2(3SO+3NH),P3(3S+HNO).The channel(7)(R →3IM8→3IM9→P1)is the dominant channel of this reaction,and the main product of the reaction is P1.The reaction rate constants of this reaction channel in the range of 298～2000 K were calculated according to the traditional transition state theory and the variable transition state theory and com-bined with tunnel correction,and the three parameters of the reaction rate constant were fitted as kCVT/Eckart=1.203 x 10-2T4 25exp(-108.29/RT)cm3·molecule-1·s-1 with a positive temperature coefficient effect.The calculated rate constants are in good agreement with literature values and apply to a wider temperature range,and the resulting kinetic parameters and thermodynamic data can be used for the establishment of the sulfur evolution mechanism in combustion.
SH radicalNOReaction mechanismRate constantDensity functional theoryDeep peaking shaving
国家科技期刊平台
NSTL
万方数据
维普
