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Abstract  

Pooling lauroyl peroxide (LPO) with nitric acid, we used differential scanning calorimetry (DSC) to assess the thermokinetic parameters, such as exothermic onset temperature (T 0), heat of decomposition (ΔH d), frequency factor (A), and the other safety parameters. When LPO was contaminated with nitric acid (HNO3), we found the exploder 1-nitrododecane. Obvious products were sensitive and hazardous chemicals. Concentration reaching 1–12 N HNO3 emitted a large amount of heat. This study combined with curve-fitting method to elucidate its unsafe characteristics and thermally sensitive structure to help prevent runaway reactions, fires and explosions in the process environment. According to the findings and the concept of inherently safer design, LPO runaway reactions could be adequately prevented in the relevant plants.

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Taiwan. The report of the investigation was applied to describe the cause involving a pipeline crack and CHP releasing. Thermal explosions and runaway reactions of CHP in the oxidation tower, reactor, and storage tank have been collected in Table 1 [ 4

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Abstract  

Tert-butyl peroxybenzoate (TBPB) is one of the sensitive and hazardous chemicals which have been popularly employed in petrifaction industries in the past. This study attempted to elucidate its unsafe characteristics and thermally sensitive structure so as to help prevent runaway reactions, fires or explosions in the process environment. We employed differential scanning calorimetry (DSC) to assess the kinetic parameters (such as exothermic onset temperature (T 0), heat of reaction (ΔH), frequency factor (A)), and the other safety parameters using four different scanning rates (1, 2, 4 and 10°C min−1) combined with curve-fitting method. The results indicated that TBPB becomes very dangerous during decomposition reactions; the onset temperature and reaction heat were about 100°C and 1300 J g−1, respectively. Through this study, TBPB accidents could be reduced to an accepted level with safety parameters under control. According to the findings in the study and the concept of inherent safety, TBPB runaway reactions could be thoroughly prevented in the relevant plants.

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Abstract  

Lauroyl peroxide (LPO) is a typical organic peroxide that has caused many thermal runaway reactions and explosions. Differential scanning calorimetry (DSC) was employed to determine the fundamental thermokinetic parameters that involved exothermic onset temperature (T0), heat of decomposition (ΔHd), and other safety parameters for loss prevention of runaway reactions and thermal explosions. Frequency factor (A) and activation energy (Ea) were calculated by Kissinger model, Ozawa equation, and thermal safety software (TSS) series via DSC experimental data. Liquid thermal explosion (LTE) by TSS was employed to simulate the thermal explosion development for various types of storage tank. In view of loss prevention, calorimetric application and model analysis to integrate thermal hazard development were necessary and useful for inherently safer design.

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Abstract  

Analytical equations related adiabatic runaway reactions to programmed scanning thermal curves from differential scanning calorimetry (DSC) were proposed. Thermal or pressure hazards can be assessed from the adiabatic trajectories expressed in the analytical equations. These industrially energetic materials include polymerizable monomers, unstable organic peroxides and nitro-compounds. Various emergency relief behaviors, such as tempered vapor, gassy, and hybrid were re-evaluated for calculating vent sizing or mass flow rates from DSC thermal curves and the related physical properties.

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time would be available for emergency response in the event of a runaway reaction. LPO is solid organic peroxide, belonging to the group of quasi-autocatalytic reactions of thermal decomposition [ 11 ]. When LPO was stored under isothermal conditions

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these reasons, MEKPO has resulted in much hazardous behavior and runaway reaction [ 12 ]. In the past, many thermal hazard incidents were caused by MEKPO in Asia, as shown in the selected serious accidents concerning MEKPO in Table 1 [ 13 , 14 ]. In

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overheating of the reaction mixture. Numerous runaway incidents are thermally initiated. It is well recognized that an exothermic runaway reaction can occur if the heat generated by the reaction exceeds that removed by the surroundings. Therefore

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Abstract  

Study of runaway reaction between tri-n-butyl phosphate (TBP) and nitric acid resulting in red-oil formation (and related problems) in the process evaporators of reprocessing plants has been a major safety concern since last 50 years. Thermal decomposition of nitrated TBP results in rapid pressurization and in close-vent condition it may lead to failure of process vessel and containment. Thermal decomposition of nitrated TBP is reported in the literature but corresponding studies for alternate PUREX/UREX solvent tri-iso-amyl phosphate (TiAP) are not available. In this work, comparative study of the thermal decomposition of nitrated solvents (TBP as well as TiAP) under adiabatic conditions in a sealed autoclave is presented. Experimental results indicate much lesser pressurization in the case of TiAP as compared to TBP.

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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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