Influence of water on HFO-1234yf oxidation pyrolysis via ReaxFF molecular dynamics simulation

ABSTRACT

The effect of water molecules on HFO-1234yf oxidation pyrolysis was investigated by ReaxFF-molecular dynamics simulation from 1900 to 4200 K. The initial pyrolysis of HFO-1234yf starts around 2500 K and the water molecules participate in chemical reactions at 2800 K when the reactants pyrolysis reached the highest reaction rate. The primary products including HF, COF₂ and CO₂ are observed at 2600, 2700 and 2900 K, respectively. The influence of water molecules on products is mainly reflected in the promotion activity on the conversion from COF₂ to CO₂ and the generation of HF molecules. Four formation pathways are observed and calculated to further elucidate the procedure of pyrolysis. The main conversion process from H₂O to HF is the •F + H₂O = HF+•OH reaction, and the paths from H₂O to •OH radical and COF₂ to •CFO radical which are promoted by •F and •H radical, respectively, have relatively low energy barriers of 10.44 and 40.29 kJ/mol, and both reaction processes released HF molecules.

GRAPHICAL ABSTRACT

KEYWORDS:

• HFO-1234yf
• molecular dynamics simulation
• water
• promotion

Additional information

Funding

This work is supported by the National Natural Science Foundation of China [grant number 51576019] and the Graduate Research and Innovation Foundation of Chongqing, China [grant number CYB17013].