PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2021
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IF 6.158
Xiao-Qiao Zhao,Wen-Qian Wu,Hua-bo Li,Zi-Chao Guo,Wang-Hua Chen,Li-Ping Chen
As a self-reactive substance, benzaldehyde oxime (BO) is prone to a highly exothermic runaway reaction and thermal hazard analysis and the reaction kinetics calculation of BO have great significance. In this work, the decomposition products of BO in nitrogen atmosphere were identified by GC–MS and HPLC techniques. The impact of the decomposition products on the decomposition behaviors of BO were analyzed by comparison of the ARC test results of pure BO and mixture of BO and decomposition products. It was found that N-benzylidene benzylamine was the intermediate decomposition product and benzoic acid , benzamide, N-benzyl benzamide, and 2,4,5-triphenylimidazole were the final products of BO. A two-step continuous autocatalytic reaction model was established to depict the decomposition process of BO. The kinetic parameters of the model were calculated by applying the nonlinear optimization method. Finally, thermal behaviors under different process temperature were predicted based on the kinetic model , and the time to maximum rate (TMR ad ) was predicted as 112.04 °C under 24 h, and 122.19 °C of 8 h, which offer crucial safety information to optimize the safety conditions of BO during usage, storage and transportation, which minimizes the industrial disasters.
研究领域:
化学工程
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安全科学
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DOI
高影响因子
AICHE JOURNAL
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2020
·Vol. 67
·期 1
·e17089
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IF 3.519
Wei Jiang,Lei Ni,Juncheng Jiang,Qiang Chen,Zhiquan Chen,Shuliang Ye
In this study, various calorimetric and analytical techniques were used to evaluate the thermodynamics of the preparation of adipic acid through the oxidation with hydrogen peroxide. The reaction exotherm was combined with the reaction mechanism. Differential scanning calorimetry revealed that the hydrogen peroxide was relatively stable when Na 2 WO 4 .2H 2 O and H 2 SO 4 were used as cocatalysts. Reaction calorimetry, in situ Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry (GC/MS) results indicated a possible macroscopic reaction pathway at 73 and 90°C stage. Furthermore, the results obtained through adiabatic calorimeter (Phi-TEC II) and GC/MS indicated the possibility of catastrophic accidents if control of the target reaction was lost. The criticality classes of this reaction were of Grade 5. The results of this study can be further used to improve the inherent safety of its operating measures, as a result, this reaction process can be scaled up.
研究领域:
化学工程
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安全科学
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分析化学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2016
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IF 4.836
Qi Sun,Lin Jiang,Liang Gong,Jin-Hua Sun
During PUREX spent nuclear fuel reprocessing, mixture of tributyl phosphate (TBP) and hydrocarbon solvent are employed as organic solvent to extract uranium in consideration of radiation contaminated safety and resource recycling, meanwhile nitric acid is utilized to dissolve the spent fuel into small pieces. However, once TBP contacts with nitric acid or nitrates above 130 °C, a heavy “red oil” layer would occur accompanied by thermal runaway reactions, even caused several nuclear safety accident. Considering nitric acid volatility and weak exothermic detection, C80 micro calorimeter technique was used in this study to investigate thermal decomposition of TBP mixed with nitric acid. Results show that the concentration of nitric acid greatly influences thermal hazard of the system by direct reactions. Even with a low heating rate, if the concentration of nitric acid increases due to evaporation of water or improper operations, thermal runaway in the closed system could start at a low temperature.
研究领域:
化学工程
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核能安全
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热分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Case Studies in Thermal Engineering
·
2023
·
IF 6.8
Haijun Cheng,Haoping Chen,Qilin Huang,Qiaoni Luo,Min Liang,Suyi Dai,Fang Lai,Li Ma,Weiguang Li,Xiongmin Liu
Although pinane has a wide range of uses, there are no reports on the safety of pinane oxidation. The thermal oxidation properties of pinane were investigated through MCPVT. The primary oxidation products of pinane were separated and structurally characterised, and its decomposition properties were assessed by MCPVT and DSC. The results showed that pinane had an initial oxygen uptake temperature of 123.5 °C and exploded when the temperature rose to 132.7 °C. Pinane autoxidised at 110 °C for 9 h formed a high level of peroxide (81.18 mmol/kg) with an activation energy of 138.77 kJ/mol. The oxidation of pinane occurs mainly at the tertiary carbon atom attached to the methyl group, and the main peroxide produced is pinane hydroperoxide (PHP). PHP has an exothermic onset temperature (T onset ), a heat of decomposition (Q DSC ) and an activation energy of decomposition of 114.6 °C, 1878.0 J/g and 109.4 kJ/mol respectively, which should classify it as a hazardous substance. PHP has a lower activation energy than pinane and is the determining factor for the safety of the pinane oxidation reaction. The products of thermal runaway of pinane are relatively complex and consist mainly of 1-(2, 2-dimethyl-3-ethylcyclobutyl) ethanone, nopinone, 2, 3-pinanediol and pinonic acid.
研究领域:
化学
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安全科学
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2018
·
IF 2.189
Jun-Cheng Jiang,Li Li,Jia-Jia Jiang,Yan Wang,Siu-Ming Lo,Yong Pan,Xu-Hai Pan,Lei Ni
Tert-butyl peroxybenzoate (TBPB) is thermally unstable organic peroxide, which may cause disasters such as fire or explosion when excessive heat released due to thermal decomposition. Ionic liquid is often used as a catalyst and inhibitor in engineering applications recently. This study investigated the thermal decomposition characteristics of TBPB when added two different ionic liquids which are 1-Propyl-3-methylimidazolium iodide ([PMIM][I]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) respectively with different mass ratio under DSC tests. Characteristic parameters such as the onset exothermic temperature (T 0 ) and heat of decomposition (ΔH d ) of samples were compared. Kinetic parameters such as activation energy E a were computed using two isoconversional methods which were Ozawa method and Friedman method respectively. The model based (zeroth order reaction) estimation method was used to estimate TMR ad at T 0 from non-isothermal DSC measurements to assess the thermal hazard of five samples. The paper aims to study the effect of ionic liquids (ILs) on the thermal decomposition of TBPB and analysis the influence of two ionic liquids on the decomposition mechanism of TBPB.
研究领域:
化学工程
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安全科学
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2022
·
IF 3.378
Wei Wang,Jiancun Gao,Yujing Li,Shengnan Wang,Chenguang Shi,Xiong Dai,Tianmeng Jiang,Guangming Sun
The thermal hazard assessment of cyclohexane-type liquid crystal monomers (CLCMs) from the Grignard cross-coupling reaction is challenging because the thermal hazard assessment involves the Grignard reagent. In this study, different calorimeters in semi-batch and batch modes were used to investigate the exothermic behaviour of CLCM. The enthalpy of formation of the Grignard reagent (320.87 - 380.46 kJ mol −1 ) was higher than that of the cross-coupling reaction (70.92 - 108.68 kJ mol −1 ). The heat accumulation in semi-batch mode decreased to 12.15% when compared with 100% observed in batch mode. Furthermore, the Grignard reagent decomposed at 470.39 K, with a low activation energy ( E a ) of 110.99 - 129.67 kJ mol −1 . Finally, based on the Stoessel criticality diagram, the thermal risk of the CLCM was found to be class 4 in batch mode and class 3 in semi-batch mode. This revealed that the semi-batch mode was the most suitable dosing method for CLCMs.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Sustainability
·
2023
·Vol. 15
·期 8
·6530
·
IF 3.9
Yinshan Liu,Lei Ni,Hang Yao,Jimi Su,Zhen Cheng
The synthesis of adipic acid, which is formed by the reaction of cyclohexene oxidized by hydrogen peroxide (H2O2), is hazardous because of the highly exothermic nature of this reaction and H2O2decomposition. The objective of this comprehensive study was to investigate and illustrate the effects of sulfuric acid (H2SO4) and H2O2stabilizer (EDTA) on the thermal hazard of H2O2decomposition and the green synthesis of adipic acid, which also provided a reference to reduce the risk of the reactions. Various calorimetry techniques were carried out to characterize the exothermic behavior of the reactions. An HPLC device was used to characterize the yield of adipic acid and the conversion rate of the raw materials, cyclohexene and H2O2. Meanwhile, density functional theory calculations were performed to understand the reaction mechanism and the associated energies of H2O2decomposition catalyzed by sodium tungstate dihydrate (Na2WO4·2H2O). Finally, combined with the calorimetry results, the risk of the adipic acid synthesis reaction was assessed using the intrinsic control index method (ITHI). The results show that the addition of H2SO4and EDTA can reduce the exothermic heat of the H2O2decomposition reaction and the green synthesis reaction of adipic acid. The yield of adipic acid was also increased. The hazard level of stage A was IV, and to remove more reaction heat, it was recommended to enhance the reflux cooling of stage A. The hazard level of stage B was I, which was very low and no further measures could be taken.Keywords:adipic acid;hydrogen peroxide decomposition reaction;hydrogen peroxide stabilizer;thermal hazard assessment
研究领域:
化学工程
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安全科学
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2013
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IF 1.989
N. Zang,X.M. Qian,P. Huang,C.M. Shu
Cyclohexanone peroxide (CYHPO) is widely used in the chemical industry, but unfortunately, as an organic peroxide, it has been involved in many serious fires and explosions in daily manufacturing, storage, and transportation. We present an advanced methodology of application of thermal analysis for thermal hazard investigation of complex chemical reactions. The applied method is based on a differential isoconversional approach and involves the combination of non-isothermal differential scanning calorimetry (DSC) and adiabatic measurements by accelerating rate calorimeter (ARC) for kinetic analysis and prediction. The kinetic parameters and heat balance were analyzed and used for a simulation of the adiabatic behavior: time to maximum rate under adiabatic conditions ( TMR ad ) and self-accelerating decomposition temperature ( SADT ). Applications of finite element analysis (FEA) for heat balance and accurate kinetic description allowed us to determine the effect of scale, geometry, heat transfer, thermal conductivity, and ambient temperature on the heat accumulation process. The presented explosion simulations of the thermal behavior of 100 kg storage tank at different temperatures, related to the possible storage scenarios, may help in the elucidation of a real accident which occurred in Beijing during CYHPO storage.
研究领域:
化学工程
·
安全科学
·
热分析
✓ 已验证
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2023
·
IF 7.8
Chuanrui Qin,Mengtao Dang,Yifei Meng,Dongfeng Zhao
The choice of thermodynamic analysis method will directly affect the accuracy of thermal hazard assessment. In this work, two advanced calorimetric experiments were used to obtain the pyrolysis parameters of 18 aromatic nitro compounds under dynamic and adiabatic conditions , aiming at the inherent thermal risk and explosion characteristics of aromatic nitro compounds in important chemical processes. The multiple linear regression (MLR) and artificial neural network (ANN) models corresponding to six typical thermodynamic analysis methods (FWO, Kissinger, Starink, Friedman, Townsend, and TMR ad ) were constructed by using the apparent activation energy (E a ) calculated by fitting as the basic sample data and combining with quantitative structure-property relationship (QSPR). Two kinds of parameters in internal and external validation were used as the main indexes to judge the accuracy and reliability of different kinetic analysis methods applied to aromatic nitro compounds. This study is expected to provide theoretical support and technical guidance for the chemical industry in the thermal hazard assessment process of nitro compounds.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2024
·
IF 5.8
Huiming Sun,Song Guo,Shuyi Shen,Renming Pan,Yitao Liu,Le Wang
Nitrogen-containing compounds are widely used as raw materials or intermediates in industries such as pharmaceuticals, dyes, explosives, and plastics. However, there is a lack of reliable and effective research methods for accurately predicting the consequences of accidents involving hazardous nitrogenous chemicals. This paper presents a novel method for simulating the combustion characteristics of nitrogen-containing hazardous chemicals, such as Hexogen (RDX) and Octogen (HMX), using multi-component gaseous small molecule fuels. The method relies on a theoretical modeling approach and numerical simulation to predict the behavior of intermediate combustion products. Key advancements include establishing a standard modeling method identifying 11 different small molecule components, and creating predictive model libraries through combinatorial methods. This approach moves away from traditional target matching by calculating proportion coefficients for each component based on their contribution to ignition characteristics. The feasibility and accuracy of this method were validated through experiments using a microscale calorimeter (MCC), demonstrating a high correlation (0.9981) between experimental results and model predictions. This method was found particularly effective for real-time prediction of thermal hazards in high-rise building scenarios, exemplified by 2-Ethylhexyl nitrate (EHN). The paper concludes with the identification of optimal multi-component models for RDX and HMX, highlighting the significant role of hydrogen cyanide (HCN) and unsaturated hydrocarbons in these models.
研究领域:
化学工程
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安全科学
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
Case Studies in Thermal Engineering
·
2025
·
IF 6.4
Juan Cheng,Chengyang Cao,Chong Xia,Guangyao Zheng,Chuan Zhang,Hongyun Hu
Nitrobenzene (NB), as a critical chemical intermediate with annual consumption exceeding one million tons, is widely used in the chemical manufacturing industry. However, its poor thermal stability when contaminated with impurities has caused multiple fire and explosion incidents. This study aims to investigate the effects of two typical phenols, p-nitrophenol (PNP) and o-nitrophenol (ONP), on the thermal behaviors of NB, and elucidate the impact mechanism. Experimental results indicate that the addition of 10% wt. PNP or ONP significantly reduces the main decomposition peak temperature of NB, initiating low-temperature exothermic reactions. Kinetic analysis reveals that while these additives increase the activation energy, the dramatic rise in pre-exponential factor indicates fundamental changes in the decomposition pathway. Specifically, NB-ONP exhibits the highest apparent activation energy due to intramolecular hydrogen bonding. Cleavage of these hydrogen bonds generates highly reactive phenoxy radicals that drive an efficient nitro-reduction pathway, leading to the most pronounced thermal hazard. Pure NB decomposition follows a second-order reaction model (F2), while mixtures with PNP or ONP conform to nucleation-growth (A3) and first-order (F1) models, respectively. Product analysis confirms that phenolic impurities reconstruct the reaction network through more complex pathways. Consequently, the thermal hazard risk follows NB-ONP>NB-PNP>NB. These findings provide crucial guidance for NB production: priority should be given to controlling high-risk ONP impurity generation by optimizing nitration process conditions to suppress relevant side reactions. The study clarifies the microscopic mechanism and provides important theoretical basis for targeted impurity management and safe NB production.
✓ 已验证
DOI
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2021
·
IF 4.237
Yuanyuan Wang,Lei Ni,Junjie Wang,Feng Xu,Juncheng Jiang,Zhiquan Chen,Gang Fu,Yong Pan
Microreactors have been widely used with advantageous of large specific surface area, excellent heat and mass transfer performance. In this paper, experimental and numerical study were carried out to analyze the thermal hazard associated with the synthesis of isopropyl propionate in a microreactor. In the experimental study, the effects of reaction temperature, catalyst amount, channel diameter and flow rate were investigated. The optimal condition was as follows: channel diameter 2 mm, amount of catalyst 0.8%, reactant ratio n(propionic anhydride): n(isopropanol) = 1:1, flow rate V (propionic anhydride + isopropanol) = 1 ml/min, and reaction temperature T = 60 °C. In this condition, the conversion of propionic anhydride reached 89.9% and the space–time yield was 2.39 × 10 6 mol m −3 h −1 . Computational Fluid Dynamics (CFD) technology was used to develop a model of the microreactor with this optimum condition. It showed that the flow rate of coolant and material of the microreactor had a great influence on the distribution of temperature. A lower cooling flow rate would lead to the formation of a heat transfer barrier in the cooling jacket. Under the same condition, a silicate glass microreactor had better heat transfer performance and was safer than other options.
研究领域:
化学工程
·
反应工程
·
过程安全
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）