The Experts below are selected from a list of 5181 Experts worldwide ranked by ideXlab platform
Tsungchih Wu - One of the best experts on this subject based on the ideXlab platform.
-
isothermal versus non isothermal calorimetric technique to evaluate thermokinetic parameters and thermal hazard of tert butyl peroxy 2 ethyl hexanoate
Journal of Thermal Analysis and Calorimetry, 2012Co-Authors: Lungchang Tsai, Yunting Tsai, Tsungchih WuAbstract:Liquid organic peroxides have been broadly employed in the process industries such as tert-butyl peroxy-2-ethyl hexanoate (TBPO). This study investigated the thermokinetic parameters of TBPO, a typical liquid organic peroxide, by isothermal kinetic algorithms and non-isothermal kinetic algorithms with thermal activity monitor III, and differential scanning calorimetry, respectively. An attempt has been made to determine the thermokinetic parameters by simulation software, such as exothermic onset temperature (T0), maximum temperature (Tmax), decomposition (∆Hd), activation energy (Ea), self-accelerating decomposition temperature, and isothermal time to maximum rate (TMRiso). A liquid thermal explosion model was established for a reactor containing liquid organic peroxide of interest. From experimental results, liquid organic peroxides’ optimal conditions for avoiding a violent runaway reaction of storage and transportation were created.
-
Thermal explosion simulation of methyl ethyl ketone peroxide in three types of vessel under the same volume by explosion models
Journal of Thermal Analysis and Calorimetry, 2011Co-Authors: Kun-yue Chen, Wei-ting Chen, Chen-wei Chiu, Tsungchih WuAbstract: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.
Akinwale O Aboyade - One of the best experts on this subject based on the ideXlab platform.
-
non isothermal kinetic analysis of the devolatilization of corn cobs and sugar cane bagasse in an inert atmosphere
Thermochimica Acta, 2011Co-Authors: Akinwale O Aboyade, Thomas Hugo, Johannes H. Knoetze, Marion Carrier, Edson L Meyer, R Stahl, Johann Ferdinand GörgensAbstract:Abstract Corn cobs and sugar cane bagasse are two of the most important agricultural residues in South Africa in terms of availability and potential for use as a bioenergy resource. The thermal devolatilization of samples of these two fuels in an inert atmosphere was studied by non-isothermal thermogravimetric analysis in the heating rate range of 10–50 °C min −1 . Friedman's isoconversional method was applied using the AKTS Thermokinetics software to obtain the dependence of activation energy on conversion. The same method was also applied to the kinetic analysis of lignocellulosic pseudocomponents derived from the mathematical deconvolution of the original DTG curves. The results showed that apparent activation energy in the 0.1–0.8 conversion interval ranged from 170–225 kJ mol −1 to 75–130 kJ mol −1 for sugar cane bagasse and corn cobs respectively. The range of apparent activation energy obtained for the pseudocomponents representing hemicelluloses, cellulose and lignin derived from sugar cane bagasse were given as 200–300 kJ mol −1 , 163–245 kJ mol −1 , and 80–180 kJ mol −1 , while for corn cobs the values were 85–110 kJ mol −1 , 80–140 kJ mol −1 , and 10–60 kJ mol −1 respectively. The derived thermokinetic parameters from both global and pseudocomponent analyses satisfactorily reproduced the experimental curves used for the analysis and could also successfully predict reaction progress at a heating rate outside what was used in the analysis. The fits obtained between simulated and experimental results were comparable to what has been reported in the literature based on conventional model-fitting techniques.
Chi-min Shu - One of the best experts on this subject based on the ideXlab platform.
-
Thermokinetic parameters and thermal hazard evaluation for three organic peroxides by DSC and TAM III
Journal of Thermal Analysis and Calorimetry, 2011Co-Authors: Shang-hao Liu, Chun-ping Lin, Chi-min ShuAbstract:The thermokinetic parameters were investigated for cumene hydroperoxide (CHP), di-tert-butyl peroxide (DTBP), and tert-butyl peroxybenzoate (TBPB) by non-isothermal kinetic model and isothermal kinetic model by differential scanning calorimetry (DSC) and thermal activity monitor III (TAM III), respectively. The objective was to investigate the activation energy ( E _a) of CHP, DTBP, and TBPB applied non-isothermal well-known kinetic equation to evaluate the thermokinetic parameters by DSC. We employed TAM III to assess the thermokinetic parameters of three liquid organic peroxides, obtained thermal runaway data, and then used the Arrhenius plot to obtain the E _a of liquid organic peroxides at various isothermal temperatures. In contrast, the results of non-isothermal kinetic algorithm and isothermal kinetic algorithm were acquired from a highly accurate procedure for receiving information on thermal decomposition characteristics and reaction hazard.
-
Thermal explosion simulation and incompatible reaction of dicumyl peroxide by calorimetric technique
Journal of Thermal Analysis and Calorimetry, 2010Co-Authors: Sunju Shen, Yihwen Wang, Jen-hao Chi, Chi-min ShuAbstract:Dicumyl peroxide (DCPO) is usually employed as an initiator for polymerization, a source of free radicals, a hardener, and a linking agent. In Asia, due to its unstable reactive nature, DCPO has caused many thermal explosions and runaway reaction incidents in the manufacturing process. This study was conducted to elucidate its essentially thermal hazard characteristics. In order to analyze the runaway behavior of DCPO in a batch reactor, thermokinetic parameters, such as heat of decomposition (Δ H _d) and exothermic onset temperature ( T _0), were measured via differential scanning calorimetry (DSC). Thermal runaway phenomena were then thoroughly investigated by DSC. The Thermokinetics of DCPO mixed with acids or bases were determined by DSC, and the experimental data were compared with kinetics-based curve fitting of thermal safety software (TSS). Solid thermal explosion (STE) and liquid thermal explosion (LTE) simulations of TSS were applied to determine the fundamental thermal explosion behavior in large tanks or drums. Results from curve fitting indicated that all of the acids or bases could induce exothermic reactions at even an earlier stage of the experiments. In order to diminish the extent of hazard, hazard information must be provided to the manufacturing process. Thermal hazard of DCPO mixed with nitric acid (HNO_3) was more dangerous than with other acids including sulfuric acid (H_2SO_4), phosphoric acid (H_3PO_4), and hydrochloric acid (HCl). By DSC, T _0, heat of decomposition (Δ H _d), and activation energy ( E _a) of DCPO mixed with HNO_3 were calculated to be 70 °C, 911 J g^−1, and 33 kJ mol^−1, respectively.
-
Thermokinetic model simulations for methyl ethyl ketone peroxide contaminated with H2SO4 OR NaOH by DSC and VSP2
Journal of Thermal Analysis and Calorimetry, 2006Co-Authors: R. H. Chang, Chi-min Shu, J.m. Tseng, Jih-mirn Jehng, H. Y. HouAbstract: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.
Johann Ferdinand Görgens - One of the best experts on this subject based on the ideXlab platform.
-
non isothermal kinetic analysis of the devolatilization of corn cobs and sugar cane bagasse in an inert atmosphere
Thermochimica Acta, 2011Co-Authors: Akinwale O Aboyade, Thomas Hugo, Johannes H. Knoetze, Marion Carrier, Edson L Meyer, R Stahl, Johann Ferdinand GörgensAbstract:Abstract Corn cobs and sugar cane bagasse are two of the most important agricultural residues in South Africa in terms of availability and potential for use as a bioenergy resource. The thermal devolatilization of samples of these two fuels in an inert atmosphere was studied by non-isothermal thermogravimetric analysis in the heating rate range of 10–50 °C min −1 . Friedman's isoconversional method was applied using the AKTS Thermokinetics software to obtain the dependence of activation energy on conversion. The same method was also applied to the kinetic analysis of lignocellulosic pseudocomponents derived from the mathematical deconvolution of the original DTG curves. The results showed that apparent activation energy in the 0.1–0.8 conversion interval ranged from 170–225 kJ mol −1 to 75–130 kJ mol −1 for sugar cane bagasse and corn cobs respectively. The range of apparent activation energy obtained for the pseudocomponents representing hemicelluloses, cellulose and lignin derived from sugar cane bagasse were given as 200–300 kJ mol −1 , 163–245 kJ mol −1 , and 80–180 kJ mol −1 , while for corn cobs the values were 85–110 kJ mol −1 , 80–140 kJ mol −1 , and 10–60 kJ mol −1 respectively. The derived thermokinetic parameters from both global and pseudocomponent analyses satisfactorily reproduced the experimental curves used for the analysis and could also successfully predict reaction progress at a heating rate outside what was used in the analysis. The fits obtained between simulated and experimental results were comparable to what has been reported in the literature based on conventional model-fitting techniques.
Sunju Shen - One of the best experts on this subject based on the ideXlab platform.
-
Thermal explosion simulation and incompatible reaction of dicumyl peroxide by calorimetric technique
Journal of Thermal Analysis and Calorimetry, 2010Co-Authors: Sunju Shen, Yihwen Wang, Jen-hao Chi, Chi-min ShuAbstract:Dicumyl peroxide (DCPO) is usually employed as an initiator for polymerization, a source of free radicals, a hardener, and a linking agent. In Asia, due to its unstable reactive nature, DCPO has caused many thermal explosions and runaway reaction incidents in the manufacturing process. This study was conducted to elucidate its essentially thermal hazard characteristics. In order to analyze the runaway behavior of DCPO in a batch reactor, thermokinetic parameters, such as heat of decomposition (Δ H _d) and exothermic onset temperature ( T _0), were measured via differential scanning calorimetry (DSC). Thermal runaway phenomena were then thoroughly investigated by DSC. The Thermokinetics of DCPO mixed with acids or bases were determined by DSC, and the experimental data were compared with kinetics-based curve fitting of thermal safety software (TSS). Solid thermal explosion (STE) and liquid thermal explosion (LTE) simulations of TSS were applied to determine the fundamental thermal explosion behavior in large tanks or drums. Results from curve fitting indicated that all of the acids or bases could induce exothermic reactions at even an earlier stage of the experiments. In order to diminish the extent of hazard, hazard information must be provided to the manufacturing process. Thermal hazard of DCPO mixed with nitric acid (HNO_3) was more dangerous than with other acids including sulfuric acid (H_2SO_4), phosphoric acid (H_3PO_4), and hydrochloric acid (HCl). By DSC, T _0, heat of decomposition (Δ H _d), and activation energy ( E _a) of DCPO mixed with HNO_3 were calculated to be 70 °C, 911 J g^−1, and 33 kJ mol^−1, respectively.
-
thermal explosion simulation and incompatible reaction of dicumyl peroxide by calorimetric technique
Journal of Thermal Analysis and Calorimetry, 2010Co-Authors: Shenghung Wu, Sunju Shen, Yihwen WangAbstract:Dicumyl peroxide (DCPO) is usually employed as an initiator for polymerization, a source of free radicals, a hardener, and a linking agent. In Asia, due to its unstable reactive nature, DCPO has caused many thermal explosions and runaway reaction incidents in the manufacturing process. This study was conducted to elucidate its essentially thermal hazard characteristics. In order to analyze the runaway behavior of DCPO in a batch reactor, thermokinetic parameters, such as heat of decomposition (ΔHd) and exothermic onset temperature (T0), were measured via differential scanning calorimetry (DSC). Thermal runaway phenomena were then thoroughly investigated by DSC. The Thermokinetics of DCPO mixed with acids or bases were determined by DSC, and the experimental data were compared with kinetics-based curve fitting of thermal safety software (TSS). Solid thermal explosion (STE) and liquid thermal explosion (LTE) simulations of TSS were applied to determine the fundamental thermal explosion behavior in large tanks or drums. Results from curve fitting indicated that all of the acids or bases could induce exothermic reactions at even an earlier stage of the experiments. In order to diminish the extent of hazard, hazard information must be provided to the manufacturing process. Thermal hazard of DCPO mixed with nitric acid (HNO3) was more dangerous than with other acids including sulfuric acid (H2SO4), phosphoric acid (H3PO4), and hydrochloric acid (HCl). By DSC, T0, heat of decomposition (ΔHd), and activation energy (Ea) of DCPO mixed with HNO3 were calculated to be 70 °C, 911 J g−1, and 33 kJ mol−1, respectively.
