二元混合工质的氧化分解机理研究

基于量子化学密度泛函理论对低全球变暖潜值工质R152a与R600a进行了氧化分解机理研究. 通过对它们的主要起始反应路径分析及能量变化情况计算，结果表明：R152a与R600a热分解的起始反应可以分为工质自身热分解和与氧气碰撞分解两类，其中工质自身热分解的反应能垒比工质与氧气反应的能垒高，并且R600a比R152a更容易发生氧化分解；在二者混合后的起始反应阶段，R600a更容易先发生分解，而链式反应中R152a与自由基的反应更占优势；两种工质与自由基的反应大部分为放热反应，可以向反应体系提供热量，促进链式反应的进行. 相关结果可为新型混合工质的氧化分解机理研究提供参考.

Study on Oxidation Decomposition Mechanism of Binary Mixtures

Based on density functional theory, the oxidative decomposition mechanism of R152a and R600a with low global warming potential (GWP) was studied. Through the calculation and analysis of their main initial reaction paths and energy changes, the results showed that the initial reactions of thermal decomposition of R152a and R600a could be divided into two categories: the thermal decomposition of the working fluid itself and the collision decomposition with oxygen. The reaction energy barriers of the thermal decomposition of the working fluids are higher than that of the reaction between the working fluids and oxygen, and R152a is more prone to oxidative decomposition than R600a. In the initial reaction stage after mixing, R600a is more likely to decompose first, and the reaction between R152a and free radicals is more dominant in the chain reaction. Most of the reactions between the two working fluids and free radicals are exothermic, which can provide heat to the reaction system and promote the chain reaction. The results can provide a reference for the study of the oxidation decomposition mechanism of new mixed working fluids.