Citation

Zhu Y, Qian Y, Xu W, Jiang J, Shi N, Wang Z. China Saf. Sci. J. 2019; 29(11): 32-38.

Copyright

(Copyright © 2019, China Occupational Safety and Health Association, Publisher Gai Xue bao)

DOI

10.16265/j.cnki.issn1003-3033.2019.11.006

PMID

unavailable

Abstract

Nitric acid oxidation is the key technology for the decolorization and refining of crude styrene. In order to investigate the thermal stability, adiabatic runaway characteristics, thermal runaway dynamics and runaway initiation mechanism of the reaction system, C600 thermal scanner, VSP2 adiabatic calorimeter, ReactIR in-situ FTIR spectrometer, combined with ReaxFF molecular dynamics simulation method were used to carry out experiments. The results show that θ0 of styrene self-polymerization runaway is 132 ℃, the Δθad is 209 ℃, the Pmax is 1. 2 MPa, the Ea is 131. 3 kJ / mol, and the reaciton order is 3. 6. The runaway process containing nitric acid is divided into two stages. The first stage is the styrene side chain oxidation reaction, and the θ0 is 51 ℃, the Δθad is 70 ℃, the Ea is 71. 3 kJ / mol, and the reaciton order is 0. 3. The second stage is styrene self-polymerization runaway, and the θ0 is 131 ℃, Δθad is 152 ℃, and Pmaxis 2. 1 MPa. In the industrial production process, it is necessary to strictly control the proportion of nitric acid in decolorization reaction, lower the reaction temperature, and prevent side reactions such as nitrification and oxidation. © 2019 China Safety Science Journal. All rights reserved.

Language: zh