POLYMER TESTING
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2020
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IF 3.275
Tao Zhou,Hang Xiao,Weifeng Peng,Bo Liang,Yao Liu,Jiangbo Lv,Jianghuai Hu,Ke Zeng,Gang Yang
The pyrolysis behaviors of l -tyrosine-based phthalonitrile(TPN) resin were investigated by thermogravimetric-Fourier transform infrared spectrometry-mass spectrometry (TG-FTIR-MS) and Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The small molecules produced during pyrolysis process of TPN resin were tracked in real time by TG-FTIR-MS. The larger molecules ( m / z > 40) from fast pyrolysis at 900 °C of the TPN resin using Py-GC/MS were identified. From TG-FTIR-MS and Py-GC/MS results, the production pathways of pyrolysis products such as CO 2 , CO, NH 3 , benzonitrile and phenol were analyzed. The possible pyrolysis mechanism of TPN resin under non-oxidizing gaseous environment was proposed. The results of this study provide the useful information for designing the molecular structure of l -tyrosine-based polymers which possessing high thermal stability.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
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2021
·Vol. 34
·期 1
·102-111
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IF 1.114
Qian Si-yu,Feng Bei-bei,Zhai Yi-tong,Zhao Wei,Wang Lei,Ao Cheng-cheng,Liu Yi,Liu Jing,Zhang Li-dong
To obtain insight into the catalytic reaction mechanism of biodiesels over ZSM-5 zeolites, the pyrolysis and catalytic pyrolysis of methyl butanoate, a biodiesel surrogate, with H-type ZSM-5 (HZSM-5) were performed in a flow re-actor under atmospheric pressure. The pyrolysis products were identified and quantified using gas chromatography-mass spectrometry (GC-MS). Kinetic modelling and experimental results revealed that H-atom abstraction in the gas phase was the primary pathway for methyl butanoate decomposition during pyrolysis, but dissociating to ketene and methanol over HZSM-5 was the primary pathway for methyl butanoate consumption during catalytic pyrolysis. The initial decomposition temperature of methyl butanoate was reduced by approximately 300 K over HZSM-5 compared to that for the uncatalyzed reaction. In addition, the apparent activation energies of methyl butanoate under catalytic pyrolysis and homogeneous pyrolysis conditions were obtained using the Arrhenius equation. The significantly reduced apparent activation energy confirmed the catalytic performance of HZSM-5 for methyl butanoate pyrolysis. The activation temperature may also affect some catalytic properties of HZSM-5. Overall, this study can be used to guide subsequent catalytic combustion for practical biodiesel fuels.
研究领域:
能源科学
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催化化学
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2026
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IF 6.7
Atinafu Abayneh Sebaro,Jinsong Luo,Minggao Xu,Chengyuan Liu,Yang Pan
Given its extensive industrial use and adverse effects on human health, trichloroethylene (TCE) is a priority environmental pollutant and a Group 1 carcinogen (IARC). Understanding its transformation under thermal conditions is essential for evaluating environmental risks associated with thermal remediation and incineration. Herein, the thermal pyrolysis of TCE was investigated in a flow-tube reactor using in situ synchrotron radiation photoionization mass spectrometry (SR-PIMS) to directly detect reactive radicals and short-lived intermediates. Key transient species, including methyl radical (•CH 3 ), propargyl radical (•C 3 H 3 ), chloromethyl radical (•CH 2 Cl), chloro-cyclopentadienyl radical (•C 5 H 4 Cl), chlorocyclopentadiene (C 5 H 5 Cl), and trichloromethyl radical (•CCl 3 ), and small molecular intermediates, were identified by their mass-to-charge ratios and photoionization efficiency (PIE) spectra. A comprehensive reaction network was constructed, encompassing initial TCE decomposition and subsequent radical-driven and molecular combination pathways leading to chlorinated and non-chlorinated aromatic species. Initial decomposition proceeds primarily through homolytic C–Cl cleavage. Chlorinated species, including C 2 Cl 2 , C 2 Cl 4 , C 4 Cl 4 , C 3 Cl 6 , C 4 Cl 6 , C 5 Cl 6 , C 6 Cl 6 , and C 8 Cl 6 , were major products at 923–1173 K and 760 Torr, while others were present in trace amounts. Reduced pressure (30 Torr) suppressed aromatic formation and favored smaller molecular species. This work provides a mechanistic framework for chlorinated hydrocarbon transformation and highlights SR-PIMS capability to probe transient intermediates in complex pyrolytic systems. Furthermore, these findings may help predict toxic byproduct formation during thermal treatment of chlorinated solvents and provide mechanistic insights relevant to emission control and remediation design.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2026
·
IF 12.5
Shuyan Guo,Ruiyang Liu,Qize Jia,Yuntian Guo,Bowen Liu,Yuan Wang,Guohui Song,Bryan R. Goldsmith,Hao Zhao
Plasma-assisted pulsed heating enables non-equilibrium CH 4 pyrolysis. • Decouples CH 4 activation and surface dehydrogenation via temporal control • CO 2 plasma removes carbon deposits and enables catalyst regeneration. Methane pyrolysis is a promising low-carbon alternative to steam methane reforming for hydrogen production, but conventional thermocatalytic approaches are limited by methane activation and high-temperature sintering, leading to low conversion and catalyst deactivation. Here, we develop a plasma-assisted pulsed heating (PPH) strategy that accesses a non-equilibrium reaction regime through dynamic plasma–thermal cycling. This approach uses a bifunctional carbon paper as both the discharge ground electrode and heating resistor to achieve localized, transient, strong electric fields (>3 × 10 6 V/m) and high temperatures (>1500 K). These conditions enable plasma-assisted methane activation and promote surface dehydrogenation by pulsed heating, resulting in high H 2 yield. As a result, PPH achieves 95% CH 4 conversion over a Ni–Fe/SiO 2 catalyst in a 0.1 CH 4 /0.9 He mixture at a pulsed-heating voltage of 46 V and a discharge voltage of 5 kV. Under pure CH 4 conditions, the minimum energy consumption of 27 kWh/kg H 2 , approximately half the typical energy consumption of water electrolysis, is achieved at a pulsed-heating voltage of 46 V and a discharge voltage of 3 kV. Beyond methane pyrolysis, this work establishes a generalizable framework for coupling non-equilibrium plasma chemistry with dynamic thermal control, with implications for chemical manufacturing. Download: Download high-res image (66KB) Download: Download full-size image
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高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2025
·
IF 6.2
Kaiwen Yun,Xixi Lian,Shuxiao Wang,Rui Shan,Haoran Yuan,Yong Chen
The development of low-cost, renewable catalysts for catalyzing the pyrolysis of waste plastics to enable selective upgrading and recycling remains a major challenge. This study reports a novel biochar-loaded calcium-based catalyst that demonstrates excellent olefin selectivity and catalytic efficiency in situ pyrolysis of polypropylene, outperforming traditional catalysts in catalytic performance. The reaction was performed using an in-house developed carbon-based calcium catalyst, which was characterized and examined using a variety of analytical test methods. The effects of catalyst calcium metal loading, feedstock/catalyst ratio and reaction temperature on pyrolysis oil yield and olefin content were investigated. The results showed that olefins and cycloalkanes were the main components of pyrolysis oil in the catalytic pyrolysis experiments, with carbon number distribution between C 13 and C 25 . Under optimal conditions (480 °C, 25% Ca loading, feedstock/catalyst ratio of 1:0.2), a maximum pyrolysis oil yield of 93.75% (0.91 g/g pp ) was achieved, with an olefin content of 58.87% (0.55 g/g pp ). The high dispersion of Ca 2+ species on the porous biochar support was found to synergistically promote C–C bond cleavage while suppressing coke formation via pore confinement and radical stabilization mechanisms. This work offers a promising strategy for the sustainable production of high-quality oils from plastic waste.
研究领域:
化学工程
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环境科学
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材料科学
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催化
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聚合物回收
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DOI
高影响因子
Environmental Chemistry Letters
·
2024
·
IF 15
Zhang Shuai,Ma Jingjing,Liu Xiangjun,Ma Yayun,Wang Junqi
Pyrolysis of modern biomass is a sustainable technique to produce chemicals, yet efficient and selective conversion remains challenging. We studied biomass pyrolysis catalyzed by graphene oxide for the production of levoglucosan, a chemical with potential applications in biodegradable plastics and surfactants. We tested model compounds containing 40–100 wt% cellulose, poplar biomass, and we modelled the role of graphene oxide by calculations using the density functional theory. Results for model compounds show that levoglucosan production is higher for compounds containing less than 50% cellulose. By contrast, levoglucosan yield are reduced for model compounds having more than 60 wt% cellulose, because graphene oxide induced the breakdown of levoglucosan. Experiments show that pyrolysis of poplar biomass with 5 wt% graphene oxide increased about three times the yield of levoglucosan, compared to non-catalyzed pyrolysis. Enhanced levoglucosan formation is explained by the formation of a six-membered ring intermediate.
研究领域:
能源科学
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催化化学
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DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
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2025
·
IF 3.5
Kexin Li,Huifang Zhang,Mingzhe Dong,Zhongmei Song,Mingzhen Li,Chunyan Wang,Haining Liu,Xiushen Ye,Guosheng Shi,Zhijian Wu
Anhydrous magnesium chloride is a conventional raw material for the electrolytic production of magnesium metal. Its preparation contributes about 50 % of the overall cost of the electrolytic production of magnesium metal. The search for a new process for the preparation of anhydrous magnesium chloride at a low cost has attracted much attention. In this study, the effects of graphene on the pyrolysis of MgCl 2 ⋅6H 2 O were investigated by comparing the thermal decomposition processes of MgCl 2 ·6H 2 O and MgCl 2 ·6H 2 O-graphene, using TG, DTG, DSC, XRD, FTIR techniques and theoretical calculations. It was found that the addition of graphene can reduce the energy barrier for the pyrolysis of MgCl 2 ⋅6H 2 O, accelerate the pyrolysis reactions, reduce the reaction temperature and energy consumption. The cation-π interactions between graphene and Mg 2+ , and the good thermal conductivity of graphene accelerate the thermal decomposition. The results obtained would be helpful for understanding the decomposition processes and mechanisms of MgCl 2 ·6H 2 O under the assistance of graphene, and for exploring new techniques for MgCl 2 ·6H 2 O dehydration.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
ENERGY & FUELS
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2024
·
IF 5.2
Yuxiang Chen,Chao Li,Lijun Zhang,Shu Zhang,Jun Xiang,Song Hu,Yi Wang,Mortaza Gholizadeh,Xun Hu
Pig manure is a typical solid waste, which features a high content of inorganics. These inorganics might be involved in thermochemical conversion of pig manure, and this was investigated herein by pyrolysis of pig manure leached with varied concentrations of H2SO4 (0.5–6 mol L–1) at 600 °C. The removal of acid-leachable inorganics [CaCO3, Ca3(PO4)2, alkaline oxides, etc.] exposed more acidic sites derived from the oxides, like SiO2. This enhanced production of the gases at the expense of bio-oil. Furthermore, aromatization and secondary condensation reactions were also promoted, increasing not only the yield of char (from 29.6 to 39.7%, on an organic basis) but also the carbon content in char from 16.1% (blank sample) to 26.2% (leached with 6 mol L–1 H2SO4). Leaching partial inorganics rendered more sufficient contact and interaction between the organics, facilitating charring of organic matter. This further retained more carbon skeleton for generation of more micropores, which further enhanced the capability of the resulting char for adsorption of phenol. In situ infrared analysis indicated the presence of more abundant oxygen-containing functionalities and carbonaceous species after the leaching treatment, favoring the occurrence of aromatization reactions.
研究领域:
环境科学
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能源转化
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DOI
高影响因子
Energies
·
2026
·Vol. 19
·期 5
·1282
·
IF 3.9
Lifang Li,Mingming Pan,Qing Huang,Yuanyong Yao,Yuhang Xu,Sen Li
Waste biomass represents both an environmental pollutant and a potential renewable energy source. This study examines the feasibility of hydrogen production from tea residue biomass and solid waste, focusing on pyrolysis-based hydrogen generation. Compared to atmospheric pyrolysis, vacuum conditions reduce the saturated vapor pressure of biomass volatiles, thereby promoting char gasification, gas-phase interactions, and secondary tar cracking. Utilizing a self-designed vacuum-pyrolysis-catalysis system, we investigated the effects of key parameters—vacuum level, temperature, catalyst-to-feedstock ratio, and retention time on pyrolysis product distribution and formation mechanisms. Results indicate that Ni was successfully and uniformly loaded onto waste calcium oxide desiccant (DC) support via impregnation, thereby significantly increasing the specific surface area of the catalyst. Optimization using response surface methodology identified the following optimal conditions: pressure of 5 kPa, temperature of 835.89 °C, catalyst/feedstock ratio of 110.02%, and retention time of 2.35 h. Under these conditions, a hydrogen yield of 256.39 mL·g−1was achieved, corresponding to 95.3% of the simulated value. The process not only enabled efficient hydrogen production but also simultaneously yielded bio-oil and biochar, thereby facilitating carbon capture and recycling. These findings provide valuable insights into the resource-oriented application of vacuum pyrolysis-catalysis technology to waste biomass.
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高影响因子
MARINE AND PETROLEUM GEOLOGY
·
2021
·
IF 4.348
Qingtao Wang,Wenhui Liu,Lixin Pei,Zhenghong Cai,Houyong Luo,Xiaofeng Wang,Dongdong Zhang,Jinzhong Liu
The total organic carbon of carbonate sediments includes a 5%–45% contribution from acid-soluble organic matter, particularly carboxylic acid salts. However, there is little information available on hydrocarbon generation from carboxylic acid salts. The objectives of this study were to investigate the extent and timing of hydrocarbon generation from calcium stearate . Thus, gold-tube nonhydrous pyrolysis experiments of calcium stearate were conducted from 250 to 600 °C at 50 MPa. Infrared spectroscopy and δ 13 C testing were also performed on solid pyrolysate and gaseous products, respectively, to trace changes of functional groups and stable carbon isotopes. Pyrolysis of calcium stearate produced hydrocarbons, CO 2 , CaO, CaCO 3 , coke, and other inorganic compounds of low molecular weight . A Van Krevelen diagram indicated that calcium stearate falls in the same region as hydrogen-rich type I kerogen. The maximum yield of methane generated from calcium stearate was as high as that from North Sea oil. Hydrocarbon generation from calcium stearate was related to cracking of the alkyl moiety and similar to that occurring in pyrolysis of n- C 18 . As a consequence of kinetic carbon isotope fractionation, with increasing temperature CO 2 becomes enriched in 13 C and CaCO 3 becomes enriched in 12 C. Notably, CaCO 3 with very low δ 13 C values is probably an effective proxy indicating hydrocarbon generation from carboxylic acid salts, if no other CaCO 3 is produced via thermochemical sulphate reduction processes. The optimized kinetic parameters demonstrate that calcium stearate had higher methane generation activation energies than those of n -C 18 and type I kerogen. Hence, methane generation from calcium stearate is delayed when extrapolated to geological conditions. This retarded methane generation illustrates the vital role of carboxylic acid salts in the generation of deep oil and gas. Future research should concern the abundance of carboxylic acid salts in carbonate formations and the depositional environments that facilitate the formation of carboxylic acid salts.
研究领域:
地质学
·
地球化学
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Menghao Chen,Bo Liang,Yuhang Guo,Chengfeng Li,Xian He,Jianghuai Hu,Renke Li,Ke Zeng,Gang Yang
The pyrolysis mechanism and pyrolysis behavior of adenine-containing polyimide (API) were studied by thermogravimetric analyzer with Fourier transform infrared analysis and mass spectrometry (TG-FTIR-MS) and pyrolysis-gas chromatography-mass spectroscopy (Py-GC-MS). TG-FTIR-MS and Py-GC-MS were employed to continuously track the release of volatile products during the pyrolysis process. Thermogravimetric analysis (TG) indicated that API presented outstanding thermal stability. Additionally, it was observed that the volatile products were formed during the pyrolysis of API, including CO 2 , CO, HCN, benzonitrile , aniline and phenyl isocyanate . A probable pyrolysis mechanism of the API has been proposed according to the results of TG-FTIR-MS and Py-GC-MS.
研究领域:
材料科学
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化学工程
·
生物分子化学
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2020
·
IF 6.785
Xiangnan Zhang,Hong Zhang,Kai Yu,Na Li,Yuning Liu,Xiangyu Liu,Hengnan Zhang,Bin Yang,Wenhai Wu,Jing Gao,Jie Jiang
Microplastics (MPs) pollution has drawn increasing concern due to its widespread occurrence and potential risks in the environment. The reliable methods and instruments for fast analysis of microplastics (MPs) less than 5 mm are urgently needed. In this study, a new method based on custom-made portable pyrolysis-mass spectrometry (Pyr-MS) is developed, which enables rapid identification and mass related quantification of MPs. MPs are decomposed in the compact pyrolyzer and then directly analyzed in the portable MS by the chemical fingerprints of polymers including characteristic ions and their special ratio. It avoids the complex extraction and separation procedures of the pyrolysis/thermogravimetric–gas chromatography–mass spectrometry (Pyr/TGA-GC-MS), realizes the rapid analysis of MPs in 5 min, and thus can practically apply to a large number of MPs samples. In comparison to Fourier transform infrared spectroscopy (FT-IR) and Raman, this method is not limited by the shape, size, and color of MPs. Four common plastics including polyethylene (PE), polypropylene (PP), polystyrene (PS), and poly(methyl methacrylate) (PMMA) were investigated to verify the feasibility of this method. The environmental MPs samples collected from a beach were successfully identified and quantified, demonstrating the simplicity and practicality of this approach. The influence of plastics aging on the chemical fingerprints and the potential of mixed plastics detection by Pyr-MS are also assessed. The portable Pyr-MS could provide a promising tool for in-field analysis of MPs such as ship-based marine MPs surveys.
研究领域:
环境科学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）