Study on the thermal decomposition behavior of methyl ethyl ketone peroxide in acid, alkali and water environments

Abstract

Methyl ethyl ketone peroxide (MEKPO) is a highly reactive chemical substance that exhibits different thermal decomposition behaviors under different environmental conditions such as acid, alkali, and water. This article uses a microcalorimeter (C80) and a thermogravimetric infrared mass spectrometry (TGA-IR-GC/MS) system to study the thermal decomposition characteristics of MEKPO doped with different mass fractions of water (H₂O), dilute sulfuric acid (H₂SO₄), and sodium hydroxide solution (NaOH), including changes in kinetic parameters and reaction pathways. The results indicate that MEKPO pyrolysis is divided into two steps, with the first stage being the main one. The reaction rate is highest at the beginning of the reaction and then decreases continuously with the increase of conversion degree. The increase in acid and water content promotes the two-step decomposition of MEKPO, reducing the initial decomposition temperature of its main exothermic peak (Peak I) by 11.8℃ and 9.3℃, respectively The total heat release increased by 40.5 % and 37.9 %. Adding alkali will make the thermal decomposition of MEKPO more concentrated in the early stage of the reaction (50–150℃), and induce two unseparated exothermic peaks during this stage. The pyrolysis products of MEKPO mainly include CH₂O₂, CH₃O, C₂H₄O₂, C₄H₈O, C₃H₆O₂, C₅H₁₂O, C₄H₁₀O₃, etc. Adding acid, alkali, and water can affect the peak time of some products, and even cause some products to completely disappear, thereby affecting the mechanism of the entire decomposition reaction.