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Several severe fires and explosions have happened in the past couple of decades. The major cause is addressed to the process reaction initiator. The cumulative heat effect can occur during processing, storage, and transportation. Acetic anhydride, one of the most crucial polymerization initiators, has been investigated in the present paper regarding its high thermal hazard risk. To analyze the thermal stability of acetic anhydride, a reaction calorimeter was used to determine the thermal parameters for stability assessment. We examined acetic anhydride samples under isothermal conditions of 40, 50, and 60 °C and considered factors such as stirring rate, feed rate, and temperature. The findings imply that the optimum operating environment for hydrolysis of acetic anhydride is 50 °C. The Arrhenius equation was used to determine the apparent activation energy of acetic anhydride hydrolysis as 57.77 kJ mol–1. A multiple nonlinear regression model was established to further confirm that the acetic anhydride reaction system was autocatalytic, along with an n-order reaction. [ABSTRACT FROM AUTHOR]

Propylene Glycol Alginate Sodium Sulfate (PSS) is widely produced and used in medicine as a marine drug for treating hyperlipidemia. During the sulfonation synthesis of PSS, the sulfonation of chlorosulfonic acid is exothermic. At high temperatures, the process can easily produce a large amount of ammonium sulfate. Ammonium sulfate adheres to PSS in crystal and participates in the sulfonation reaction. In this study, the sulfonation process of commercial PSS was reproduced in the laboratory using chlorosulfonic acid and formamide. We used differential scanning calorimetry and thermogravimetric analyzer to examine the thermal stability of PSS, and we used both differential and integral conversional methods to determine the appropriate thermokinetic models for this substance. We also established an autocatalytic model to study the conversion limit time and the maximum rate time of this substance. After calculation, the activation energy of this substance is no more than 60 kJ/mol, and it has other exothermic performances at different heating rates. The results help to optimize the sulfonation process of PSS and analyze the thermal risk of PSS with ammonium sulfate. [ABSTRACT FROM AUTHOR]

In recent years, a number of cosmeceutical incidents have occurred both domestically and internationally. These incidents range from minor burns on the skin to the explosion of a cosmeceutical factory. In most of these incidents, benzoyl peroxide (BPO) was reported as one of the hazardous compounds involved. Even after dilution, BPO still poses a hazard. This study examined the thermal stability parameters of BPO by using differential scanning calorimetry, thermogravimetric analyzer, and thermal activity monitor III. Advanced thermokinetic models were integrated and calculated, and complete thermal stability analysis of low concentration of BPO was conducted. The findings of this study may be used as a reference in future research on BPO decomposition. [ABSTRACT FROM AUTHOR]

1,1-Bis( tert-butylperoxy)-3,3,5 trimethylcyclohexane (TMCH), a typical organic peroxide, is normally an initiator agent and cross-linking agent of styrene and polyethylene. Metal ions, used as catalysis substances, can affect the thermal stability of TMCH. However, they are commonly found everywhere in processing areas such as in rusty rotating equipment, metal containers, and aging pipelines. Thus, we investigated the thermal stability of TMCH mixed with metal ions and acquired thermokinetic parameters using calorimetric data. Through isoconversional kinetic analysis simulations, thermokinetic parameters were obtained under isothermal conditions using nonisothermal experimental data. In DSC experiments, the E of TMCH mixed with CuCl was lower than that of pure TMCH. TMR of pure TMCH was shorter than that of TMCH mixed with CuCl in isothermal experiments. The results of the simulations and experiments were compared and discovered to be similar. The results can be a reference for TMCH mixing with metal ions during its storage and transportation. [ABSTRACT FROM AUTHOR]