Explosion evaluation and safety storage analyses of cumene hydroperoxide using various calorimeters

Plenty of thermal explosions and runaway reactions of cumene hydroperoxide (CHP) were described from 1981 to 2010 in Taiwan. Therefore, a thermal explosion accident of CHP in oxidation tower in 2010 in Taiwan was investigated because of piping breakage. In general, high concentration of CHP for thermal analysis using the calorimeter is dangerous. Therefore, a simulation method and a kinetic parameter were used to simulate thermal hazard of high concentrations of CHP only by the researcher. This study was applied to evaluate thermal hazard and to analyze storage parameters of 80 and 88 mass% CHP using three calorimeters for the oxidation tower, transportation, and 50-gallon drum. Differential scanning calorimetry (DSC) (a non-isothermal calorimeter), thermal activity monitor III (TAM III) (an isothermal calorimeter), and vent sizing package 2 (VSP2) (an adiabatic calorimeter) were employed to detect the exothermic behavior and runaway reaction model of 80 and 88 mass% CHP. Exothermic onset temperature (T ₀), heat of decomposition (ΔH _d), maximum temperature (T _max), time to maximum rate under isothermal condition (TMR_iso) (as an emergency response time), maximum pressure (P _max), maximum of self-heating rate ((dT/dt)_max), maximum of pressure rise rate ((dP/dt)_max), half-life time (t _1/2), reaction order (n), activation energy (E _a), frequency factor (A), etc., of 80 and 88 mass% CHP were applied to prevent thermal explosion and runaway reaction accident and to calculate the critical temperature (T _c). Experimental results displayed that the n of 80 and 88 mass% CHP was determined to be 0.5 and the E _a of 80 and 88 mass% CHP were evaluated to be 132 and 134 kJ mol^?1, respectively.     

Effects of cumene hydroperoxide on phenol and acetone manufacturing by DSC and VSP2

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.     

Reactivity in the solid-state between ZnWO<Subscript>4</Subscript> and some rare-earth metal molybdates RE<Subscript>2</Subscript>MoO<Subscript>6</Subscript> (<Emphasis Type="Italic">RE</Emphasis>=Y,Sm, Eu,Gd, Dy,Ho, Er and Lu)

Organic peroxides (OPs) have caused many momentous explosions and runaway reactions, resulting from thermal instability, chemical pollutants, and even mechanical shock. In Taiwan, dicumyl peroxide (DCPO), due to its unstable reactive nature, has caused two thermal explosions and runaway reaction incidents in the manufacturing process. To evaluate thermal hazards of DCPO in a batch reactor, we studied thermokinetic parameters, such as heat of decomposition (†H _d), exothermic onset temperature (T ₀), maximum temperature rise ((dT/dt)_max), maximum pressure rise ((dP/dt)_max), self-heating rate (dT/dt), etc., via differential scanning calorimetry (DSC) and vent sizing package 2 (VSP2).     

Thermal runaway reaction evaluation of two by-products mixed with cumene hydroperoxide in the oxidation tower

Oxygen (O₂) or air is widely used to produce cumene hydroperoxide (CHP) in the cumene oxidation tower. The aim of this study was applied to analyze thermal hazard of two by-products including alpha-methylstyrene (AMS) and acetophenone (AP) in a CHP oxidation tower. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were operated to evaluate thermal runaway reaction of CHP mixed with AMS and AP. Exothermic onset temperature (T ₀), maximum temperature (T _max), activation energy (E _a), etc., that were employed to prevent and protect thermal runaway reaction and explosion in the manufacturing process and storage area. In view of proactive loss prevention, the inherently safer handling procedure and storage situation should be maintained in the chemical industries. The T ₀ of 30 mass% CHP was determined to be 105 °C by DSC. Therefore, the T ₀ of 30 mass% CHP mixed with AMS was determined to be 60–70 °C by DSC. The exothermic reaction of CHP/AP and CHP/AMS by DSC under N₂ reaction gas is thermal decomposition of oxygen–oxygen bond (–O–O–) because of the anaerobic reaction.     

Evaluation of thermal hazard for lauroyl peroxide by VSP2 and TAM III

When above certain temperature limits, lauroyl peroxide is an unstable material. If the thermal source cannot be properly governed during any stage in the preparation, manufacturing process, storage or transport, runaway reactions may inevitably be induced immediately. In this study, the influence of runaway reactions on its basic thermal characteristic was assessed by evaluating thermokinetic parameters, such as activation energy (E _a) and frequency factor (A) by thermal activity monitor III (TAM III). This was achieved under five isothermal conditions of 50, 60, 70, 80, and 90?°C. Vent sizing package 2 (VSP2) was employed to determine the maximum pressure (P _max), maximum temperature (T _max ), maximum self-heating rate ((dT?dt ^?1)_max), maximum pressure rise rate ((dP?dt ^?1)_max), and isothermal time to maximum rate ((TMR)_iso) under the worst case. Results of this study will be provided to relevant plants for adopting best practices in emergency response or accident control.     

Thermal hazard evaluation for methyl ethyl ketone peroxide mixedwith inorganic acids

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.     

Evaluation of adiabatic runaway reaction of methyl ethyl ketone peroxide by DSC and VSP2

Methyl ethyl ketone peroxide (MEKPO) is generally applied to manufacturing in the polymerization processes. Due to thermal instability and high exothermic behaviors of MEKPO, if any operation is undertaken recklessly or some environmental effect is produced suddenly during the processes, fires and explosions may inevitably occur. In this study, thermal analysis was evaluated for MEKPO by differential scanning calorimetry (DSC) test. Vent sizing package 2 (VSP2) was used to analyze the thermal hazard of MEKPO under various stirring rates in a batch reactor. Thermokinetic and safety parameters, including exothermic onset temperature (T ₀), maximum temperature (T _max), maximum pressure (P _max), self-heating rate (dT dt ⁻¹), pressure rise rate (dP dt ⁻¹), and so on, were discovered to identify the safe handling situation. The stirring rates of reactor were confirmed to affect runaway and thermal hazard characteristics in the batch reactor. If the stirring rate was out of control, it could soon cause a thermal hazard in the reactor.     

Thermokinetic model simulations for methyl ethyl ketone peroxide contaminated with H2SO4 OR NaOH by DSC and VSP2

In this study, a mixture of methyl ethyl ketone peroxide (MEKPO) with various contaminants, such as H₂SO₄ and NaOH, was prepared in order to elucidate the cause of these accidents and the results of upset conditions. Thermokinetic parameters were acquired by both differential scanning calorimetry (DSC) and vent sizing package 2 (VSP2). In addition, we simulated the thermokinetic parameters and created kinetic models for the specific contaminants. The results indicate that the thermal hazard of MEKPO is less than that of the mixed MEKPO with the above-mentioned contaminants. Consequently, the evaluated parameters could be used to prevent any unexpected exothermic runaway reaction or to alleviate hazards to an acceptable extent, if such a reaction occurs.     

Kinetics and thermodynamics of thermal decomposition of synthetic AlPO<Subscript>4</Subscript>·2H<Subscript>2</Subscript>O

Cumene hydroperoxide (CHP) and its derivatives have caused many serious explosions and fires in Taiwan as a consequence of thermal instability, chemical contamination, and even mechanical shock. It has been employed in polymerization for producing phenol and dicumyl peroxide (DCPO). Differential scanning calorimetry (DSC) was used to analyze the thermal hazard of CHP in the presence of sodium hydroxide (NaOH), sulfuric acid (H₂SO₄), and sodium bisulfite (Na₂SO₃). Thermokinetic parameters for decomposition, such as exothermic onset temperature (T ₀ ), maximum temperature (T _max ), and enthalpy (ΔH), were obtained from the thermal curves. Isothermal microcalorimetry (thermal activity monitor, TAM) was employed to investigate the thermal hazards during CHP storage and CHP mixed with NaOH, H₂SO₄, and Na₂SO₃ under isothermal conditions in a reactor or container. Tests by TAM indicated that from 70 to 90 °C an autocatalytic reaction was apparent in the thermal curves. According to the results from the TAM test, high performance liquid chromatography (HPLC) was, in turn, adopted to analyze the result of concentration versus time. By the Arrhenius equation, the activation energy (E _a ) and rate constant (k) were calculated. Depending on the process conditions, NaOH was one of the incompatible chemicals or catalysts for CHP. When CHP is mixed with NaOH, the T ₀ is induced earlier and the reactions become more complex than for pure CHP, and the E _a is lower than for pure CHP.     

Thermal explosion simulation of methyl ethyl ketone peroxide in three types of vessel under the same volume by explosion models

Methyl ethyl ketone peroxide (MEKPO), which has highly reactive and exothermically unstable characteristics, has been extensively employed in the chemical industries. It has also caused many thermal explosions and runaway reaction accidents in manufacturing processes during the last three decades in Taiwan, Japan, Korea, and China. The goal of this study was to simulate thermal upset by MEKPO for an emergency response. Vent sizing package 2 (VSP2) was used to determine the thermokinetics of 20 mass% MEKPO. Data of thermokinetics and hazard behaviors were employed to simulate thermal explosion in three types of vessel containing 20 mass% MEKPO under various scenarios at the same volume. To compare and appraise the difference of important parameters, such as maximum temperature (T _max), maximum pressure (P _max), etc. This was necessary and useful for investigating the emergency response procedure associated with industrial applications.     

Reaction hazard analysis for cumene hydroperoxide with sodium hydroxide or sulfuric acid

Organic peroxides (OPs) are very susceptible to thermal sources, chemical pollutants or even mechanical shock. Over the years, they have caused many serious explosions. Cumene hydroperoxide (CHP) is widely employed to produce phenol and dicumyl peroxide (DCPO) in the manufacturing process. Differential scanning calorimetry (DSC) and thermal activity monitor (TAM) were employed to determine the potential thermal hazards and thermokinetic parameters (such as exothermic onset temperature (T ₀), maximum temperature (T _max), and enthalpy (ΔH)) of CHP mixed with sodium hydroxide (NaOH) and sulfuric acid (H₂SO₄). High performance liquid chromatography (HPLC) was used to analyze the concentration vs. time of CHP.When CHP is mixed with NaOH, the T ₀ is induced earlier and reactions become more intricate than the pure CHP solution. CHP added to NaOH or H₂SO₄ is more dangerous than pure CHP alone. Depending on the operating conditions, NaOH and H₂SO₄ are the incompatible chemicals for CHP.     

Runaway effects of nitric acid on methyl ethyl ketone peroxide by TAM III tests

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.     

Reaction hazard analysis for the thermal decomposition of cumene hydroperoxide in the presence of sodium hydroxide

Organic peroxides have caused many serious explosions and fires that were promoted by thermal instability, chemical pollutants, and even mechanical shock. Cumene hydroperoxide (CHP) has been employed in polymerization and for producing phenol and dicumyl peroxide (DCPO). Differential scanning calorimetry (DSC) has been used to assess the thermal hazards associated with CHP contacting sodium hydroxide (NaOH). Thermokinetic parameters, such as exothermic onset temperature (T ₀), peak temperature (T _max), and enthalpy (ΔH) were obtained. Experimental data were obtained using DSC and curve fitting using thermal safety software (TSS) was employed to obtain the kinetic parameters. Isothermal microcalorimetry (thermal activity monitor, TAM) was used to investigate the thermal hazards associated with storing of CHP and CHP mixed with NaOH under isothermal conditions. TAM showed that in the temperature range from 70 to 90°C an autocatalytic reaction occurs. This was apparent in the thermal curves. Depending on the operating conditions, NaOH may be one of the chemicals or catalysts incompatible with CHP. When CHP was mixed with NaOH, the T ₀ is lower and reactions become more complex than those associated with assessment of the decomposition of the pure peroxide. The data by curve fitting indicated that the activation energy (E _a) for the induced decomposition is smaller than that for decomposition of CHP in the absence of hydroxide.     

Thermal hazard evaluations of 18650 lithium-ion batteries by an adiabatic calorimeter

In this study, the thermal hazard features of various lithium-ion batteries, such as LiCoO₂ and LiFePO₄, were assessed properly by calorimetric techniques. Vent sizing package 2 (VSP2), an adiabatic calorimeter, was used to measure the thermal hazards and runaway characteristics of the 18650 lithium-ion batteries under an adiabatic condition. The thermal behaviors of the lithium-ion batteries were obtained at normal and abnormal conditions in this study. The critical parameters for thermal hazardous behavior of lithium-ion batteries were obtained including the exothermic onset temperature (T ₀), heat of decomposition (ΔH), maximum temperature (T _max), maximum pressure (P _max), self-heating rate (dT/dt), and pressure rise rate (dP/dt). Therefore, the result indicates the thermal runaway situation of the lithium-ion battery with different materials and voltages in view the of TNT-equivalent method by VSP2. The hazard gets greater with higher voltage. Without the consideration of other anti-pressure measurements, different voltages involving 3.3, 3.6, 3.7, and 4.2 V are evaluated to 0.11, 0.23, 0.88, and 1.77 g of TNT. Further estimation of thermal runaway reaction and decomposition reaction of lithium-ion battery can also be confirmed by VSP2. It shows that the battery of a fully charged state is more dangerous than that of a storage state. The technique results showed that VSP2 can be used to strictly evaluate thermal runaway reaction and thermal decomposition behaviors of lithium-ion batteries. The loss prevention and thermal hazard assessment are very important for development of electric vehicles as well as other appliances in the future. Therefore, our results could be applied to define important safety indices of lithium-ion batteries for safety concerns.     

Effects of various fire-extinguishing reagents for thermal hazard of triacetone triperoxide (TATP) by DSC/TG

Acetone, hydrogen peroxide (H₂O₂), and sulfuric acid (H₂SO₄) are easily to produce triacetone triperoxide (TATP), which is an organic peroxide and a hazardous material. The aim of this study was to analyze the thermal hazard of various fire-extinguishing reagents mixed with TATP. Various functions of fire-extinguishing reagents may have different extent of reactions with TATP. Differential scanning calorimetry (DSC) and thermogravimetric analyzer (TG) were used to detect the thermal hazard and to evaluate the effect of fire-extinguishing reagents mixed with TATP under fire condition. TATP decomposed rapidly and final decomposition was calculated before 200 °C. Therefore, heat of decomposition (ΔH _d) of TATP was evaluated to be 2,500 J g^?1 by DSC under 2 °C min^?1 of heating rate. H₂O₂, acetone, and H₂SO₄ should not be mixed in a wastewater drum. TATP decomposed at 50 °C by DSC using O₂ of reaction gas that is an exothermic reaction and can decompose a large amount of heat. Therefore, TATP was applied to assess thermal pyrolysis by DSC employing N₂ of reaction gas that can analyze an endothermic reaction. Mass loss percentage of TATP was evaluated to be 100 % when the ambient temperature exceeds 110 °C by TG using O₂ or N₂ of reaction gas.     

Self-reactive rating of thermal runaway hazards on 18650 lithium-ion batteries

Vent sizing package 2 (VSP2) was used to measure the thermal hazard and runaway characteristics of 18650 lithium-ion batteries, which were manufactured by Sanyo Electric Co., Ltd. Runaway reaction behaviors of these batteries were obtained: 50% state of charge (SOC), and 100% SOC. The tests evaluated the thermal hazard characteristics, such as initial exothermic temperature (T ₀), self-heating rate (dT?dt ^?1), pressure-rise rate (dP?dt ^?1), pressure temperature profiles, maximum temperature, and pressure which were observed by adiabatic calorimetric methodology via VSP2 using customized test cells. The safety assessment of lithium-ion cells proved to be an important subject. The maximum self-heating rate (dT?dt ^?1)_max and the largest pressure-rise rate (dP?dt ^?1)_max of Sanyo 18650 lithium-ion battery of 100% SOC were measured to be 37,468.8???C?min^?1 and 10,845.6?psi?min^?1, respectively, and the maximum temperature was 733.1???C. Therefore, a runaway reaction is extremely serious when a lithium-ion battery is exothermic at 100% SOC. This result also demonstrated that the thermal VSP2 is an alternative method of thermal hazard assessment for battery safety research. Finally, self-reactive ratings on thermal hazards of 18650 lithium-ion batteries were studied and elucidated to a deeper extent.     

Thermal hazard evaluation of tert-butyl hydroperoxide mixed with four acids using calorimetric approaches

Possessing thermal instability inherently, organic peroxides have caused many severe accidents in chemical industries all over the world. tert-Butyl hydroperoxide (TBHP) is usually used as initiator or oxidant because of its strong oxidizing ability in the chemical process. In this study, the thermal hazard analysis of TBHP mixed with various acids was investigated. Differential scanning calorimetry (DSC) and vent sizing package 2 were used to figure out the thermal runaway behaviors of TBHP. Thermokinetic parameters, such as exothermic onset temperature (T ₀), maximum temperature (T _max), and enthalpy (ΔH), were obtained from thermal curves. In addition, the activation energy (E _a) and rate constant (k) were calculated by the Arrhenius equation. Therefore, the T ₀ was determined to be 91.6 °C for exothermic reaction using DSC under 4 °C min^?1 of heating rate. The E _a for exothermic reaction was calculated to be 92.38 kJ mol^?1 by DSC in this study. As far as loss prevention is concerned, thermokinetic parameters are crucial to the relevant processes in the chemical industries, particularly under process upsets.     

Thermal hazard evaluation of tert-butyl peroxide using non-isothermal and adiabatic calorimetric approaches

Tert-butyl peroxide (TBPO), is a typical organic peroxides (OPs),which is widely applied as initiator in poly-glycidyl methacrylate (PGMA) reaction, and is employed to provide a free-radical in frontal polymerization, and which has also caused many thermal runaway reactions and explosions worldwide. To find an unknown and insufficient hazard information for an energetic material, differential scanning calorimetry (DSC) and vent sizing package 2 (VSP2) were employed to detect the fundamental thermokinetic parameters involving the exothermic onset temperature (T ₀), heat of decomposition (??H _d), temperature rise rate (dT · dt ^?1), time to maximum rate under adiabatic situation (TMR_ad), pressure rise rate (dP · dt ^?1), and maximum pressure (P _max), etc. The T ₀ was calculated to be 130?°C using DSC and VSP2. Activation energy (E _a) of TBPO was evaluated to be 136?kJ?mol^?1 by VSP2. In view of the loss prevention, calorimetric applications and model evaluation to integrate thermal hazard development are adequate means for inherently safer design.     

Role of interlayer M k atoms and H2O molecules in the structure formation of M k (VUO6) k · nH2O uranovanadates

M ^k (VUO₆) _k · nH₂O uranovanadates of alkali (Li, Na, K, Rb, Cs), alkaline-earth (Mg, Ca, Sr, Ba), 3d transition (Mn, Fe, Co, Ni, Cu, Zn), and rare-earth (Y, La, Ln) elements were prepared by precipitation from solutions under hydrothermal conditions and in solid-phase reactions. The composition and structure of these compounds and the role of M ^k atoms and H₂O molecules in the formation of their structure were studied by X-ray diffraction, IR-spectroscopy, thermal analysis, and chemical analysis.     

Effects of mixing metal ions for the thermal runaway reaction of TMCH

1,1-bis(tert-Butylperoxy)-3,3,5-trimethylcyclohexane (TMCH) is commonly used as a crosslinking agent or an initiator of the heat-curing agent for polybutadiene rubber. Metal ions that remain in the pipelines or containers of manufacturing processes may affect the thermal stability of the organic peroxides. Moreover, pipelines or metal containers may contain some metal ions because of inner corrosive chemicals or surface deterioration, which may induce a chemical reaction, while TMCH is mixed with them. To avoid these unexpected chemical reactions, we focused on the thermal hazard analysis of TMCH mixed with metal ions, such as nickel(II) bromide or copper(II) bromide. The experiments can determine thermokinetic parameters, including exothermic onset temperature (T ₀), maximum temperature (T _max), and heat of decomposition (ΔH _d), under non-isothermal conditions by differential scanning calorimetry. Non-isothermal experimental results combined with isoconversional kinetic analysis can acquire further safety parameters, such as apparent activation energy (E _a) and time to maximum heating rate. The results of this study could be used as a proactive case for the storage of TMCH mixed with metal ions.