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tert-Butyl hydroperoxide (TBHP, 70 mass %), which is a solution of liquid peroxide, has been widely employed in the chemical industry as a polymerization initiator. The smart technology for predicting the mechanism of thermal decomposition and the inhibitive or hazardous reaction of TBHP by different calorimetric tests involves using differential scanning calorimetry (DSC) nonisothermal tests versus DSC isothermal tests and vent sizing package 2 (VSP2) adiabatic tests versus DSC nonisothermal tests, respectively, for further understanding how to extinguish organic peroxide accidents under fire scenario or runaway reaction in a chemical plant. Meanwhile, TBHP mixed with inhibitive and hazardous materials, such as various protic acids to help prevent runaway reactions, was applied on fires or explosions in the fire system. The results could be available to fire-related agencies as a reference application. The fire extinguishing system must be well-designed to decrease the degree of hazard.

tert-Butyl peroxy-2-ethyl hexanoate (TBPO), an organic peroxide broadly used as initiator for polymerization of ethylene, styrene, methyl methacrylate, and acrylonitrile, has the characteristic of triggering a highly exothermic reaction. Mixing with a contaminant, such as metal ions, may result in a runaway reaction and acceleration decomposition under an abnormal situation. We investigated how Cu2+, Ni2+, and Fe2+ individually affected the thermal decomposition of TBPO. Our aim was to explore the thermal hazard of TBPO mixed with metal ions by calorimetric techniques combined with thermokinetic models. We employed nonisothermal and isothermal calorimeters to determine various thermokinetic and safety parameters, including exothermic onset temperature (To), peak temperature (Tp), final temperature (Tf), heat of decomposition (ΔHd), and maximum heat flow (Qmax) by differential scanning calorimetry (DSC) and thermal activity monitor III (TAM III). Moreover, the isothermal and nonisothermal kinetic models we...

Flammability limits are two of the most important variables used to assess the fire and explosion hazards of gases and vapors, and inerting is frequently used in industry to reduce fire and explosion hazards. A model based on the energy balance equation that takes into account thermal radiation loss and constant flame temperature was developed to estimate the flammability envelope of fuel–air–diluent mixtures tested in a constant pressure vessel. The validation of the model was done by comparing the estimated values with the corresponding experimental data for methane, ethylene, propane, propylene, isobutane, and methyl formate with nitrogen or carbon dioxide as the inert gas. The difference in the estimated flammability envelopes between the different heat loss considerations is small. The predictions of the lower flammability limits are in excellent agreement with the experimental data, except for the region approaching the limiting oxygen concentration, where the assumption of complete consumption of t...

The thermal stability of solutions of methyl ethyl ketone peroxide (MEKPO) dissolved in dimethyl phthalate (DMP), in the presence of nitric acid (HNO3) and sodium nitrate (NaNO3) as contaminants, was studied. MEKPO is extensively employed in the chemical industries, but despite its large use several severe accidents have been recorded in eastern Asia during the past four decades. This study was conducted to elucidate its essentially hazardous characteristics. We used differential scanning calorimetry (DSC) to evaluate the root cause of the runaway reactions, and kinetics-based curve fitting to assess hazardous phenomena by utilizing curve fitting to optimize the kinetic parameters. All the results indicate that the mixture of MEKPO with HNO3 dramatically increases the degree of hazard in the first exothermic peak. In terms of NaNO3, it had no effect on the thermal stability of MEKPO.

In the past 4 decades in Japan and Taiwan, many thermal explosions have been caused by methyl ethyl ketone peroxide (MEKPO) subjected to external heating including fire. Thermograms of commercialized MEKPO dimers were first screened by differential scanning calorimetry (DSC) to determine the heat of decomposition and exothermic onset temperature. Thermal runaway phenomena were then thoroughly investigated using Vent Sizing Package2. Instead of the normal one-reaction peak for the MEKPO dimer seen in the adiabatic calorimeter, two distinct exothermic peaks occurred in the DSC thermograms near 110 and 170 °C, indicative of series reactions. The onset temperature of the MEKPO monomer was determined to be about 40 °C, showing it to be extremely reactive under storage or process conditions. Thermokinetic and related data were obtained that can be used for hazard analysis to prevent thermal explosions in both the monomer and the dimer.

Cumene hydroperoxide (CHP) has been used in producing phenol and acetone by catalytic cleavage and as an initiator in polymerization. However, many severe fires and explosions have occurred because of its thermal instability and incompatibility. In fact, CHP has been given a hazard classification of flammable type or Class III by the National Fire Protection Association (NFPA). To date, however, its reactive and incompatible hazards have not yet been clearly identified. In this study, the thermal decomposition and runaway behaviors of CHP with about 1 wt % incompatibilities such as H2SO4, HCl, NaOH, KOH, Fe2O3, FeCl3, and Fe2(SO4)3 were analyzed by DSC thermal analysis and VSP2 adiabatic calorimetry. The thermokinetic data obtained via calorimetry, such as onset temperature, heat of decomposition, adiabatic temperature rise, and self-heat rate, were also compared with those of CHP in cumene. Hydroxide ion and ferric ion were found to be quite incompatible with CHP. The worst case of thermal runaway of CHP...