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Abstract  

Methyl ethyl ketone peroxide (MEKPO) is an unstable material above certain limits of temperature, decomposing into chain reactions by radicals. The influence of runaway reactions on this basic characteristic was assessed by evaluating kinetic parameters, such as activation energy (E a), frequency factor (A), etc., by thermal activity monitor III (TAM III). This was done under three isothermal conditions of 70, 80, and 90 °C, with MEKPO 31 mass% combined with nitric acid (HNO3 6 N) and sodium nitrate (NaNO3 6 N). Nitric acid mixed with MEKPO gave the maximum heat of reaction (△H d) and also induced serious reactions in the initial stage of exothermic process under the three isothermal temperatures. The time to maximum rate (TMR) also decreased when HNO3 was mixed with MEKPO. Thus, MEKPO combined with HNO3 6 N forms a very hazardous mixture. Results of this study will be provided to relevant plants for alerting their staff on adopting best practices in emergency response or accident control.

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rate of decomposition was shown to exponentially increase with temperature and pressure. Determining time to maximum rate (TMR), SADT, maximum temperature ( T max ), exothermic onset temperature ( T 0 ), and heat of decomposition ( ΔH d ) is essential

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temperature ( T 0 ), time to maximum rate ( TMR ), maximum temperature ( T max ), maximum pressure ( P max ), Δ H d , activation energy ( E a ), maximum self-heating rate ((d T d t −1 ) max ), and maximum pressure rise rate ((d P d t −1 ) max ) can be

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Journal of Thermal Analysis and Calorimetry
Authors: Sheng-Hung Wu, Hung-Cheng Chou, Ryh-Nan Pan, Yi-Hao Huang, Jao-Jia Horng, Jen-Hao Chi, and Chi-Min Shu

reaction rate. (11) (12) (13) where Q acc is heat of accumulation that was used to investigate the critical development in three cooling system circumstances. Typically, time to maximum rate (TMR) is adopted to analyze the degree of safety

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Abstract  

Methyl ethyl ketone peroxide (MEKPO) possesses complex structures which have caused many incidents involving fires or explosions by mixing with incompatible substances, external fires, and others. In this study, reactivities or incompatibilities of MEKPO with inorganic acids (HCl, HNO3, H3PO4 and H2SO4) were assessed by differential scanning calorimetry (DSC) and vent sizing package 2 (VSP2). Parameters obtained by the above-mentioned devices could be readily employed to discuss the runaway reaction, such as onset temperature (T 0), heat of reaction (ΔH d), time to maximum rate (TMR), maximum self heat rate (dT/dt)max, adiabatic temperature rise (ΔT ad), maximum pressure of decomposition (P max) and so on. Mixing MEKPO with hydrochloric acid resulted in the lowest T 0 among inorganic acids. Nitric acid not only lowered the T 0 but also delivered the highest heat releasing rate or self heat rate (dT/dt), which was concluded to be the worst case in terms of contamination hazards during storage or transportation of MEKPO.

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Abstract  

Over 90% of the cumene hydroperoxide (CHP) produced in the world is applied in the production of phenol and acetone. The additional applications were used as a catalyst, a curing agent, and as an initiator for polymerization. Many previous studies from open literature have verified and employed various aspects of the thermal decomposition and thermokinetics of CHP reactions. An isothermal microcalorimeter (thermal activity monitor III, TAM III), and a thermal dynamic calorimetry (differential scanning calorimetry, DSC) were used to resolve the exothermic behaviors, such as exothermic onset temperature (T 0), heat power, heat of decomposition (ΔH d), self-heating rate, peak temperature of reaction system, time to maximum rate (TMR), etc. Furthermore, Fourier transform infrared (FT-IR) spectrometry was used to analyze the CHP products with its derivatives at 150 °C. This study will assess and validate the thermal hazards of CHP and incompatible reactions of CHP mixed with its derivatives, such as acetonphenone (AP), and dimethylphenyl carbinol (DMPC), that are essential to process safety design.

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Abstract  

Cumene hydroperoxide (CHP) being catalyzed by acid is one of the crucial processes for producing phenol and acetone globally. However, it is thermally unstable to the runaway reaction readily. In this study, various concentrations of phenol and acetone were added into CHP for determination of thermal hazards. Differential scanning calorimetry (DSC) tests were used to obtain the parameters of exothermic behaviors under dynamic screening. The parameters included exothermic onset temperature (T 0), heat of decomposition (ΔH d), and exothermic peak temperature (T p). Vent sizing package 2 (VSP2) was employed to receive the maximum pressure (P max), the maximum temperature (T max), the self-heating rate (dT/dt), maximum pressure rise rate ((dP/dt)max), and adiabatic time to maximum rate ((TMR)ad) under the worst case. Finally, a procedure for predicting thermal hazard data was developed. The results revealed that phenol and acetone sharply caused a exothermic reaction of CHP. As a result, phenol and acetone are important indicators that may cause a thermal hazard in the manufacturing process.

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of 1, 2, 4, and 10 °C min −1 ) first. Then they were further simulated using TSS by n th order and autocatalytic reaction processes, respectively. In addition, the thermal hazard parameters of LPO, time to maximum rate (TMR), and a certain time

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required data. By TAM III, the obtained thermal runaway data, such as heat flow ( Q ), reaction rate constant ( k iso ), and time to maximum rate ( TMR iso ) can be fully exploited for thermal hazard evaluation and emergency planning, as well as for

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experiment is the time to maximum rate (TMR). It is the time period available before the occurrence of an incident at any specific temperature in the worst case of damage [ 10 ]. Based on this time, alarm temperatures will be set, and the time available for

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