Theoretical Studies on Mechanism and Rate Constant of Gas Phase Hydrolysis of Glyoxal Catalyzed by Sulfuric Acid  

硫酸催化乙二醛气体相查化反应机理和速率常数理论计算研宄

作　　者：黄明强[1,2,3] 蔡顺有 廖颖敏[3] 赵卫雄 胡长进 王振亚[4] 张为俊[4] 

机构地区：[1]闽南师范大学化学与环境学院,漳州363000 [2]福建省现代分离分析科学与技术重点实验室,漳州363000 [3]厦门大学嘉庚学院环境科学与工程系,漳州363105 [4]中国科学院安徽光学精密机械研究所大气物理化学实验室,合肥230031

出　　处：《Chinese Journal of Chemical Physics》2016年第3期335-343,I0001,I0002,共11页化学物理学报（英文）

摘　　要：The gas phase hydration of glyoxal （HCOCHO） in the presence of sulfuric acid （H2SO4） were studied by the high-level quantum chemical calculations with M06-2X and CCSD（T） theoretical methods and the conventional transition state theory （CTST）. The mechanism and rate constant of the five different reaction paths are consid- ered corresponding to HCOCHO＋H2O, HCOCHO＋H2O… H2O, HCOCHO… H2O＋H2O, HCOCHO＋H2O… H2SO4 and HCOCHO… H2O＋H2SOa. Results show that H2SO4 has a strong catalytic ability, which can significantly reduce the energy barrier for the hydration reaction of glyoxal. The energy barrier of hydrolysis of glyoxal in gas phase is lowered to 7.08 kcal/mol from 37.15 kcal/mol relative to pre-reactive complexes at the CCSD（T）/6- 311＋＋G（3df, 3pd）//M06-2X/6-311＋＋G（3df, 3pd） level of theory. The rate constant of the H2SO4 catalyzed hydrolysis of glyoxal is 1.34×10-11 cm3/（molecule.s）, about 1013 higher than that involving catalysis by an equal number of water molecules, and is greater than the reaction rate of glyoxal reaction with OH radicals of 1.10×10-11 cm3/（molecule·s） at the room temperature, indicating that the gas phase hydrolysis of glyoxal of H2SO4 catalyst is feasible and could compete with the reaction glyoxal＋OH under certain atmospheric condi- tions. This study may provide useful information on understanding the mechanistic features of inorganic acid-catalyzed hydration of glyoxal for the formation of oligomer.

关 键 词：GLYOXAL HYDROLYSIS Sulfuric acid Acid-catalyzed mechanism 

分 类 号：O[理学]