几种催化剂对HN(NO_2)_2→HONONNO_2氢迁移反应的影响  

The effect of several kinds of catalysts on hydrogen transfer process of HN(NO_2)_2→HONONNO_2 cracked reaction

作　　者：王睿[1] 张梦甜 蓝新广 杨晨 刘金花 

机构地区：[1]陕西理工学院化学与环境科学学院陕西省催化基础与应用重点实验室,陕西汉中723000

出　　处：《西北师范大学学报（自然科学版）》2017年第4期74-79,共6页Journal of Northwest Normal University(Natural Science)

基　　金：陕西理工学院大学生创新创业训练计划项目(UIRP15095)

摘　　要：采用CBS-QB3方法对HN(NO_2)_2→HONONNO_2氢迁移反应机理和速率常数进行了理论研究,并在此基础上考虑了H_2O,CH_3OH,HCOOH,HONO_2和H_2SO_4对该反应过程的影响.结果表明,HN(NO_2)_2→HONONNO_2氢迁移过程需克服162.76kJ·mol-1的能垒.H_2O,CH_3OH,HCOOH,HONO_2和H_2SO_4等催化剂的加入改变了原有反应机理,即由裸反应中的直接抽氢变为双氢原子转移.就能垒而言,上述催化剂的加入均使HN(NO_2)_2→HONONNO_2的能垒降低了36.68~96.42kJ·mol^(-1),其中CH_3OH的参与降低的幅度最大.此外在200~420K范围内CH_3OH参与通道R3的速率常数k_(R3)比相同温度下裸反应通道R1的速率常数k_(R1)大1.7×10~5~6.1×10^(28)倍,说明在200~420K时CH_3OH的催化效果最好.In this article , the hydrogen abstraction mechanisms of HN （NO2 ）2 to HONONNO2 without and with catalyst X（X= H2 O ,CH3 OH ,HCOOH ,HONO2 and H2 SO4 ） have been investigated theoretically at the CBS-QB3 level of theory , coupled with rate constant calculations by using conventional transition state theory . The results show that the hydrogen abstraction reaction of HN （NO2 ）2 to HONONNO2 without catalysts overcomes the barrier height of 162.76 kJ·mol^-1 . With the addition of catalyst X , the direct hydrogen abstraction mechanism changes to double hydrogen abstraction . Compared to the hydrogen abstraction mechanisms of HN （NO2 ）2 to HONONNO2 without catalysts , the energy barrier of the reaction with catalyst X reduces by 36.68-96.42 kJ·mol^-1 , and the energy barrier of the reaction with CH3 OH is the lowest . Besides , the rate constant of CH3 OH-assisted the reaction of HN （NO2 ）2 to HONONNO2 is predicted to be faster by 1.7 × 10^5 -6.1 × 10^28 times than that of the naked reaction at the temperature range of 200-420 K . This indicates that CH3 OH is the most positive catalytic for the title reaction in temperature range 200-420 K .

关 键 词：二硝酰胺酸(HDN) 催化剂 氢迁移 反应机理 

分 类 号：O643.322[理学—物理化学]