Low-Pressure and Nascent Yields of Thermalized Criegee Intermediate in Ozonolysis of Ethene
Low-Pressure and Nascent Yields of Thermalized Criegee Intermediate in Ozonolysis of Ethene
复制标题
乙烯臭氧分解热化 Criegee 中间体的低压和初期产率
DOI：
10.1021/acs.jpclett.2c02940
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Zhang, Jingsong
中科院分区：
文献类型：
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作者：
Yang, Lei;Campos-Pineda, Mixtli;Zhang, Jingsong
采用光腔衰荡光谱法（CRDS）和化学滴定法，以过量的二氧化硫（SO2）间接测定了乙烯在低压下臭氧分解生成的热氧化甲醛（CH 2 OO，最简单的Criegee中间体）的产率。监测SO2作为清除剂的消耗的方法允许在低压和短停留时间下更好地表征CH 2 OO。乙烯臭氧化热分解产物CH_2OO的产率随压力的降低而降低。通过将7-19托测量值外推到零压力极限，确定了热化CH 2 OO的新生产率为20.1 ± 2.5%。动力学模型可以更好地评估和理解热化Criegee中间体的不同测量方法。从这项工作的低压产率的信息作为一个基准的理论计算，有利于更好地理解烯烃臭氧分解反应机制。
The yields of thermalized formaldehyde oxide (CH2OO, the simplest Criegee intermediate) produced from ozonolysis of ethene at low pressures were measured indirectly using cavity ringdown spectroscopy (CRDS) and chemical titration with an excess amount of sulfur dioxide (SO2). The method of monitoring the consumption of SO2as a scavenger allows better characterization of the CH2OO at low pressure and short residence time. The yield of thermalized CH2OO from ethene ozonolysis was found to decrease with decreasing pressure. The nascent yield of thermalized CH2OO was determined to be 20.1 ± 2.5% by extrapolation of the 7–19 Torr measurements to the zero-pressure limit. Kinetic models enable better evaluation and understanding of the different measurement methods of thermalized Criegee intermediates. The information on the low-pressure yields from this work serves as a benchmark for theoretical calculations and facilitates a better understanding of the alkene ozonolysis reaction mechanisms.