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Qingsheng Wang - One of the best experts on this subject based on the ideXlab platform.
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thermal hazard assessment and ranking for Organic Peroxides using quantitative structure property relationship approaches
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Ronghua Qi, Pei He, Ruiqing Shen, Jiajia Jiang, Lei Ni, Juncheng Jiang, Qingsheng WangAbstract:Chemical reactivity hazards of Organic Peroxides are major concerns of the chemical industry due to many serious incidents every year. Thermal hazard assessment for Organic Peroxides is of great importance for safe operations in chemical process industries. A new hazard evaluation method based on quantitative structure–property relationship (QSPR) was proposed to assess thermal hazard of Organic Peroxides from their molecular structures. Optimal molecular descriptors were determined to characterize thermal hazard parameters, including onset temperature (To), time to maximum rate under adiabatic condition (TMRad) and heat of reaction (ΔH), respectively. Both the probability and severity of the thermal risk were considered to evaluate the thermal hazards of Organic Peroxides comprehensively. To and TMRad were employed to describe the probability of thermal risk, while ΔH was used to describe the severity. Then, the thermal hazard rating was developed based on the molecular descriptors and a corresponding ranking criterion was also proposed with the thermal hazards being divided into five levels. After comparing and verifying with previously developed evaluation methods, the proposed assessment method in this work would be reasonably expected to provide an accurate ranking of the thermal hazards for Organic Peroxides.
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Thermal hazard assessment and ranking for Organic Peroxides using quantitative structure–property relationship approaches
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Ronghua Qi, Pei He, Ruiqing Shen, Jiajia Jiang, Lei Ni, Juncheng Jiang, Qingsheng WangAbstract:Chemical reactivity hazards of Organic Peroxides are major concerns of the chemical industry due to many serious incidents every year. Thermal hazard assessment for Organic Peroxides is of great importance for safe operations in chemical process industries. A new hazard evaluation method based on quantitative structure–property relationship (QSPR) was proposed to assess thermal hazard of Organic Peroxides from their molecular structures. Optimal molecular descriptors were determined to characterize thermal hazard parameters, including onset temperature (To), time to maximum rate under adiabatic condition (TMRad) and heat of reaction (ΔH), respectively. Both the probability and severity of the thermal risk were considered to evaluate the thermal hazards of Organic Peroxides comprehensively. To and TMRad were employed to describe the probability of thermal risk, while ΔH was used to describe the severity. Then, the thermal hazard rating was developed based on the molecular descriptors and a corresponding ranking criterion was also proposed with the thermal hazards being divided into five levels. After comparing and verifying with previously developed evaluation methods, the proposed assessment method in this work would be reasonably expected to provide an accurate ranking of the thermal hazards for Organic Peroxides.
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prediction of the self accelerating decomposition temperature of Organic Peroxides using qspr models
Journal of Thermal Analysis and Calorimetry, 2017Co-Authors: Hang Yi, Beibei Wang, Kaili Xu, Qingsheng WangAbstract:Organic Peroxides are widely used unstable compounds that have caused many serious industrial incidents. Self-accelerating decomposition temperature (SADT) is one of the most important parameters to describe the thermal instability hazards of Organic Peroxides. However, it is very difficult to obtain experimental data of SADT due to high cost, the time involved and safety issues of laboratory tests. Quantitative structure–property relationship (QSPR) models have been proposed as an effective tool to predict thermal stability of Organic Peroxides. In this work, a dataset including 50 SADTs of Organic Peroxides was built and their molecular descriptors were calculated at B3LYP/6-31G(d) level using Gaussian 09. Two novel predictive models were successfully developed by multiple linear regression (MLR) and support vector machine (SVM). Both models were validated to have an excellent goodness of fit, internal robustness and external predictive ability. The MLR model was a linear equation with the average absolute error of training set and test set being 9.78 and 9.91, while the SVM model was a nonlinear model with the two values being 4.33 and 5.75, respectively. The SVM model has higher accuracy and is much more effective than the MLR model. This research provides general guidelines and methodology of establishing QSPR models to predict SADTs for other Organic Peroxides and unstable hazardous chemicals.
D. Huang - One of the best experts on this subject based on the ideXlab platform.
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Organic Peroxides gas-particle partitioning and rapid heterogeneous decomposition on secondary Organic aerosol
Atmospheric Chemistry and Physics Discussions, 2015Co-Authors: H. Li, Z. M. Chen, L. B. Huang, D. HuangAbstract:Abstract. Organic Peroxides, important species in the atmosphere, will promote secondary Organic aerosols (SOA) aging, affect HOx radicals cycling, and cause adverse health effects. However, the formation, gas-particle partitioning, and evolution of Organic Peroxides are extremely complicated and still unclear. In this study, we investigate in the laboratory the production and gas-particle partitioning of Peroxides from the ozonolysis of α-pinene, which is one of the major biogenic volatile Organic compounds in the atmosphere and is an important precursor for SOA at a global scale. We have determined the molar yields of hydrogen peroxide (H2O2), hydroxymethyl hydroperoxide (HMHP), peroxyformic acid (PFA), peroxyacetic acid (PAA) and total Peroxides (TPO, including unknown Peroxides) and the fraction of Peroxides in SOA. Comparing the gas-phase and particle-phase Peroxides, we find that gas-particle partitioning coefficients of PFA and PAA are 104 times higher than theoretical prediction, indicating that Organic Peroxides play a more important role in the SOA formation than expected previously. Here, we give the partitioning coefficients of TPO as (2–3) × 10-4 m3μg-1. Even so, more than 80 % of the Peroxides formed in the reaction remain in the gas phase. Water does not affect the total amount of Peroxides in either the gas or particle phase, but can change the distribution of gaseous Peroxides. About 18 % gaseous Peroxides undergo rapid heterogeneous decomposition on SOA particles in the presence of water vapor, resulting in the additional production of H2O2. This process can partially interpret the unexpected high H2O2 yield under wet conditions. Transformation of Organic Peroxides to H2O2 also saves OH in the atmosphere, helping to improve the understanding of OH cycling.
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Organic Peroxides gas particle partitioning and rapid heterogeneous decomposition on secondary Organic aerosol
Atmospheric Chemistry and Physics, 2015Co-Authors: H. Li, Zhongming Chen, D. Huang, Liubin HuangAbstract:Abstract. Organic Peroxides, important species in the atmosphere, promote secondary Organic aerosol (SOA) aging, affect HOx radicals cycling, and cause adverse health effects. However, the formation, gas-particle partitioning, and evolution of Organic Peroxides are complicated and still unclear. In this study, we investigated in the laboratory the production and gas-particle partitioning of Peroxides from the ozonolysis of α-pinene, which is one of the major biogenic volatile Organic compounds in the atmosphere and an important precursor for SOA at a global scale. We have determined the molar yields of hydrogen peroxide (H2O2), hydromethyl hydroperoxide (HMHP), peroxyformic acid (PFA), peroxyacetic acid (PAA), and total Peroxides (TPOs, including unknown Peroxides) and the fraction of Peroxides in α-pinene/O3 SOA. Comparing the gas-phase Peroxides with the particle-phase Peroxides, we find that gas-particle partitioning coefficients of PFA and PAA are 104 times higher than the values from the theoretical prediction, indicating that Organic Peroxides play a more important role in SOA formation than previously expected. Here, the partitioning coefficients of TPO were determined to be as high as (2–3) × 10−4 m3 µg−1. Even so, more than 80 % of the Peroxides formed in the reaction remain in the gas phase. Water changes the distribution of gaseous Peroxides, while it does not affect the total amount of Peroxides in either the gas or the particle phase. Approx. 18 % of gaseous Peroxides undergo rapid heterogeneous decomposition on SOA particles in the presence of water vapor, resulting in the additional production of H2O2. This process can partially explain the unexpectedly high H2O2 yields under wet conditions. Transformation of Organic Peroxides to H2O2 also preserves OH in the atmosphere, helping to improve the understanding of OH cycling.
Juncheng Jiang - One of the best experts on this subject based on the ideXlab platform.
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thermal hazard assessment and ranking for Organic Peroxides using quantitative structure property relationship approaches
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Ronghua Qi, Pei He, Ruiqing Shen, Jiajia Jiang, Lei Ni, Juncheng Jiang, Qingsheng WangAbstract:Chemical reactivity hazards of Organic Peroxides are major concerns of the chemical industry due to many serious incidents every year. Thermal hazard assessment for Organic Peroxides is of great importance for safe operations in chemical process industries. A new hazard evaluation method based on quantitative structure–property relationship (QSPR) was proposed to assess thermal hazard of Organic Peroxides from their molecular structures. Optimal molecular descriptors were determined to characterize thermal hazard parameters, including onset temperature (To), time to maximum rate under adiabatic condition (TMRad) and heat of reaction (ΔH), respectively. Both the probability and severity of the thermal risk were considered to evaluate the thermal hazards of Organic Peroxides comprehensively. To and TMRad were employed to describe the probability of thermal risk, while ΔH was used to describe the severity. Then, the thermal hazard rating was developed based on the molecular descriptors and a corresponding ranking criterion was also proposed with the thermal hazards being divided into five levels. After comparing and verifying with previously developed evaluation methods, the proposed assessment method in this work would be reasonably expected to provide an accurate ranking of the thermal hazards for Organic Peroxides.
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Thermal hazard assessment and ranking for Organic Peroxides using quantitative structure–property relationship approaches
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Ronghua Qi, Pei He, Ruiqing Shen, Jiajia Jiang, Lei Ni, Juncheng Jiang, Qingsheng WangAbstract:Chemical reactivity hazards of Organic Peroxides are major concerns of the chemical industry due to many serious incidents every year. Thermal hazard assessment for Organic Peroxides is of great importance for safe operations in chemical process industries. A new hazard evaluation method based on quantitative structure–property relationship (QSPR) was proposed to assess thermal hazard of Organic Peroxides from their molecular structures. Optimal molecular descriptors were determined to characterize thermal hazard parameters, including onset temperature (To), time to maximum rate under adiabatic condition (TMRad) and heat of reaction (ΔH), respectively. Both the probability and severity of the thermal risk were considered to evaluate the thermal hazards of Organic Peroxides comprehensively. To and TMRad were employed to describe the probability of thermal risk, while ΔH was used to describe the severity. Then, the thermal hazard rating was developed based on the molecular descriptors and a corresponding ranking criterion was also proposed with the thermal hazards being divided into five levels. After comparing and verifying with previously developed evaluation methods, the proposed assessment method in this work would be reasonably expected to provide an accurate ranking of the thermal hazards for Organic Peroxides.
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Prediction of the self-accelerating decomposition temperature of Organic Peroxides based on support vector machine
Procedia Engineering, 2018Co-Authors: Pei He, Juncheng JiangAbstract:Abstract Organic Peroxides are self-reactive substances that are susceptible to decomposition and redox reactions under external energy, causing catastrophic accidents such as fires and explosions. Self-accelerating decomposition temperature (SADT) is one of the most important parameters for describing the thermal hazard of Organic Peroxides in process industries. This study presented a quantitative structure-property relationship (QSPR) model to predict the SADT of 71 Organic Peroxides through their molecular structures. All molecular descriptors are calculated by DRAGON 6.0 software. Genetic algorithm (GA), along with multiple linear regression (MLR) was employed to select the optimal subset of descriptors. Two different models are developed by employing multiple linear regression (MLR) and support vector machine (SVM), respectively. Both models are considered to be valid and able to predict the SADT of Organic Peroxides through rigorous model validations. The average absolute error of the MLR model for the training set and test set is 7.976 ℃ and 8.585 ℃, while that for the SVM model is 5.676 ℃ and 8.172 ℃, respectively. The predicted results showed that the SVM model has an obvious superiority in prediction performance when comparing to the MLR one. This study could provide a new method for predicting the SADT of Organic Peroxides for engineering.
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the Organic Peroxides instability rating research based on adiabatic calorimetric approaches and fuzzy analytic hierarchy process for inherent safety evaluation
Process Safety Progress, 2016Co-Authors: Lei Ni, Juncheng Jiang, Zhirong Wang, Yuan Song, Yuan YuAbstract:This article proposes a new method of instability classification of Organic Peroxides (ICOP) for assessing the risk of decomposition reaction of Organic Peroxides, based on the adiabatic calorimetric approaches and fuzzy analytic hierarchy process (FAHP). Tonset is set as instability possibility index. Maximal power density, adiabatic temperature rise, maximum pressure rate, and maximum pressure are set as instability severity index (ISI) with proper weightings by FAHP. Instability possibility index and ISI are converted into ICOP based on risk matrix. The Organic Peroxides instability can, therefore, be quantified and divided into four levels, acceptable, moderate risk, highly dangerous, and seriously dangerous. Thermal decomposition of di-tert-butyl peroxide 25 mass % and tert-butyl hydroperoxide 68.4 mass % are tested with Vent Sizing Package 2 and Phi-Tech 1 which has the function of Accelerating Rate Calorimeter, respectively. Thermal decompositions of other Organic Peroxides are presented from citation. The instability rating results of these Organic Peroxides are presented to illustrate the validity of the method. © 2015 American Institute of Chemical Engineers Process Saf Prog, 2015
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prediction of the self accelerating decomposition temperature of Organic Peroxides using the quantitative structure property relationship qspr approach
Journal of Loss Prevention in The Process Industries, 2014Co-Authors: Yinyan Zhang, Juncheng Jiang, Li DingAbstract:Abstract The reactivity hazard of Organic Peroxides has been reported as one of the main causes for fire and explosion in process industries. The self-accelerating decomposition temperature ( SADT ) is one of the most important thermal hazard parameters for risk assessment and safe management of Organic Peroxides during storage and transportation. This study proposed a quantitative structure–property relationship (QSPR) model to predict the SADT of Organic Peroxides for the estimation of their thermal stability and reactivity hazards, from only the knowledge of their molecular structures. Various kinds of molecular descriptors were calculated to represent the molecular structures of Organic Peroxides. Genetic algorithm based multiple linear regression is employed to select optimal subset of descriptors that have significant contribution to the overall SADT property. The best resulted model is a six-variable multilinear model with the average absolute error for the external test set being 5.7 °C. Model validation was performed to check the stability and predictivity of this model. The results showed that the model is valid and predictive. The mean effect method was also performed to identify the relative significance of each descriptor contributing to the thermal hazards of Organic Peroxides. The proposed study can provide a new, quick and easy applicable way to predict the SADT of Organic Peroxides for identifying the reactivity hazards that may lead to safe practices in the process industries for engineering.
Carlo Adamo - One of the best experts on this subject based on the ideXlab platform.
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prediction of the thermal decomposition of Organic Peroxides by validated qspr models
Journal of Hazardous Materials, 2014Co-Authors: Vinca Prana, Patricia Rotureau, Guillaume Fayet, David Andre, Patricia Vicot, Carlo AdamoAbstract:Abstract Organic Peroxides are unstable chemicals which can easily decompose and may lead to explosion. Such a process can be characterized by physico-chemical parameters such as heat and temperature of decomposition, whose determination is crucial to manage related hazards. These thermal stability properties are also required within many regulatory frameworks related to chemicals in order to assess their hazardous properties. In this work, new quantitative structure–property relationships (QSPR) models were developed to predict accurately the thermal stability of Organic Peroxides from their molecular structure respecting the OECD guidelines for regulatory acceptability of QSPRs. Based on the acquisition of 38 reference experimental data using DSC (differential scanning calorimetry) apparatus in homogenous experimental conditions, multi-linear models were derived for the prediction of the decomposition heat and the onset temperature using different types of molecular descriptors. Models were tested by internal and external validation tests and their applicability domains were defined and analyzed. Being rigorously validated, they presented the best performances in terms of fitting, robustness and predictive power and the descriptors used in these models were linked to the peroxide bond whose breaking represents the main decomposition mechanism of Organic Peroxides.
Klausdieter Wehrstedt - One of the best experts on this subject based on the ideXlab platform.
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prediction of the self accelerating decomposition temperature sadt for liquid Organic Peroxides from differential scanning calorimetry dsc measurements
Journal of Hazardous Materials, 2005Co-Authors: Marcus Malow, Klausdieter WehrstedtAbstract:We present a prediction (estimation, calculation, screening) method for the estimation of the self-accelerating decomposition temperature (SADT) for liquid Organic Peroxides from differential scanning calorimetry (DSC) measurements based on the concepts of thermal explosion theory originally introduced by Semonov which are adopted to our problem assuming nth-order reaction kinetics. For the Peroxides under investigation, we demonstrate good agreement with the experimental SADT. This method can be used as a quick and easy applicable method for the estimation of the critical temperatures.
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evaluation of the validity of the un sadt h 4 test for solid Organic Peroxides and self reactive substances
Journal of Hazardous Materials, 2005Co-Authors: M Steensma, Marcus Malow, P Schuurman, Ulrich Krause, Klausdieter WehrstedtAbstract:Abstract Many self-accelerating decomposition temperatures (SADTs) of solid Organic Peroxides and self-reactive substances have been determined with the UN test method H.4, which is a scaled down test in a small Dewar vessel. For solid Organic Peroxides and solid self-reactive substances Fierz has questioned this procedure in a recent paper. Fierz concluded that the Dewar test results should not be extrapolated to beyond 8 l packages, owing to the thermal insulation value of solids. On the other hand, long term experience with the test, with a great variety of solid Organic Peroxides and self-reactive substances show about equal critical temperatures in the small Dewar vessel and on 50 kg scale. In the present work, we first checked, by numerical simulations, the Dewar scale versus the larger scale, in a way comparable with Fierz’ method: both scales are simulated by spheres, consisting of a number of annular layers, for the large scale the usual external heat loss term is used but for the small scale the outside heat transfer is strongly limited. The outcome of these simulations, covering a variety of physical parameters, supports the concerns expressed by Fierz. After this, we performed accurate cooling and heating experiments with solid Organic peroxide in the usual Dewar vessel, provided with a large set of thermocouples. The results of these experiments showed that the simulation model for the Dewar vessel has to be changed from a spherical analogue to a short cylinder of solid material with heat exchange mainly via its top ( U top ∼ 3.5 W/(m 2 K), overall heat transfer coefficient) and some heat exchange ( U side ∼ 0.29 W/(m 2 K)) through its cylindrical and bottom part. With this “modified cylinder” model (being neither an infinitely long cylinder nor a slab) of the Dewar vessel, we found that the UN method H.4 enables an accurate prediction of the SADT, with small deviations of 0 ± 2.5 °C. Further, by performing a truly three-dimensional (3D) finite element calculation in FEMLAB, the new heat characteristics of the Dewar vessel as well as a 50 kg package of dilauroyl peroxide, a solid Organic peroxide, were checked. The outcome was compared with the critical ambient temperatures known for various package sizes, which agreed well.
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the mini closed pressure vessel test mcpvt as a screening or classification test for explosive properties of Organic Peroxides
Journal of Loss Prevention in The Process Industries, 2003Co-Authors: Klausdieter Wehrstedt, Annett Knorr, P SchuurmanAbstract:Tests according to the UN Recommendations on the Transport of Dangerous Goods for the determination of explosive properties of Organic Peroxides have been compared with screening criteria for explosivity based on measurements in a closed mini-autoclave (MCPVT). It will be shown that an additional screening test may be helpful but the information obtained from the UN tests are more important to characterise the specific properties of a substance under different conditions.