FUEL
·
2025
·
IF 7.5
Ruotong Cui,Wenlong Xu,Yanpeng Zhang,Jingxian Wang,Yingyun Qiao,Yuanyu Tian
Identifying and analyzing the reaction process of S atoms in coal at the molecular level has been a key and difficult problem in coal chemistry. Here, we used dibenzyl sulfide as a model compound for S-containing substances in coal and predicted the pyrolysis process of C-S in coal through the pyrolysis products, which indicated that the C-S bond would be broken firstly above the energetic basis point to generate intermediate S-containing radicals. A hydrogen-donating solvent (9, 10-dihydroanthracene) was utilized as the radical trapping agent to reveal the S-containing radical reaction process through the changes of the products before and after the trapping reaction. Density functional theory was further used to calculate the pyrolysis process to help verify the radical history of the response. Finally, pyrolysis experiments were performed on raw coal to confirm the generality of the pyrolytic radical regulatory mechanism of C-S. This study identifies and analyzes the relationship between C-S structure and reactivity during coal pyrolysis at the molecular level, and confirms the universal law of raw coal’s pyrolytic radical reaction mechanism. This not only provides theoretical guidance and a basis for the free radical regulation process during the pyrolysis of S-containing structures in coal but also provides theoretical support for the clean and efficient utilization of coal.
研究领域:
煤炭化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2025
·
IF 5.3
Xi Shen,Zhenyu Zhao,Hong Li,Xin Gao
The recycling and upcycling of waste plastics into high-value products by pyrolysis is a critical challenge caused by its time/energy-consuming problems, which can be overcome by employing microwave-assisted catalytic pyrolysis due to its rapid pyrolysis rates and high product yields. This study presents a facile method for the synthesis of catalysts for microwave-assisted pyrolysis of waste plastics, utilizing the pyrolytic products as raw materials. In this case, a microwave thermal shock strategy is developed to efficiently anchor iron nanoparticles on carbon nanotubes (CNTs). This method recycles a portion of pyrolysis products back into the catalyst pool for plastic transformation into new CNTs, reducing the consumption for preparing additional catalysts. The precursors exposed to 50 W microwave irradiation reaches above 2000 °C within seconds, allowing Fe nanoparticles to be uniformly impregnated within the carbon nanotube matrix. The formed iron-doped CNTs shows high activity for microwave-assisted pyrolysis, generating CNTs with D/G ratios at 0.31. The recycling and reconstruction of CNTs after multiple pyrolysis form a cross-lined network structure, which facilitates electron transition and can be utilized for fabricating electrocatalysts. Nitrogen doping further improves the onset potential to 0.923 V vs. RHE, making them viable candidates for electrocatalytic applications in oxygen reduction reactions. In summary, our findings demonstrate the feasibility of this approach to reactive pyrolysis products that serve as catalysis for microwave-assisted pyrolysis, with the potential to reduce volatile organic compound emissions and capital expenditure in catalyst preparation, offering a greener and more efficient pathway for plastic waste management and catalyst production.
研究领域:
材料科学
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环境科学
·
化学工程
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产品关联
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2022
·Vol. 17
·期 1
·1-12
·
IF 6.048
Yin Xiaoxiao,Tao Junyu,Chen Guanyi,Yao Xilei,Luan Pengpeng,Cheng Zhanjun,Li Ning,Zhou Zhongyue,Yan Beibei
Pyrolysis is considered an attractive option and a promising way to dispose waste plastics. The thermogravimetric experiments of high-density polyethylene (HDPE) were conducted from 105 °C to 900 °C at different heating rates (10 °C/min, 20 °C/min, and 30 °C/min) to investigate their thermal pyrolysis behavior. We investigated four methods including three model-free methods and one model-fitting method to estimate dynamic parameters. Additionally, an artificial neural network model was developed by providing the heating rates and temperatures to predict the weight loss (wt.%) of HDPE, and optimized via assessing mean squared error and determination coefficient on the test set. The optimal MSE (2.6297 × 10 −2 ) and R 2 value ( R 2 > 0.999) were obtained. Activation energy and pre-exponential factor obtained from four different models achieves the acceptable value between experimental and predicted results. The relative error of the model increased from 2.4 % to 6.8 % when the sampling frequency changed from 50 s to 60 s, but showed no significant difference when the sampling frequency was below 50 s. This result provides a promising approach to simplify the further modelling work and to reduce the required data storage space. This study revealed the possibility of simulating the HDPE pyrolysis process via machine learning with no significant accuracy loss of the kinetic parameters. It is hoped that this work could potentially benefit to the development of pyrolysis process modelling of HDPE and the other plastics.
研究领域:
化学工程
·
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Scientific Reports
·
2021
·Vol. 11
·期 1
·1-12
·
IF 4.38
Wu Shibin,Chen Yan,Chen Zhenshou,Wang Jiaqi,Cai Miaomiao,Gao Junkai
Metal microspheres doping porous carbon (MMPC), which was prepared using in-situ pyrolysis reduction strategy, could enhance the thermal conductivity of shape-stabilized phase change material (ss-PCM) prepared by MMPC as the matrix. However, in previous studies that were reported, the preparation of MMPC needed to synthesize porous carbon by pyrolysis firstly, and then porous carbon adsorbed metal ions was pyrolyzed again to obtain MMPC, which was tedious and energy-prodigal. In this study, a one-step pyrolysis strategy was developed for the synthesis of MMPC through the pyrolyzation of wheat bran adsorbed copper ions, and the copper microspheres doping wheat bran biochar (CMS-WBB) was prepared. The CMS-WBB was taken as the supporter of stearic acid (SA) to synthesize the ss-PCM of SA/CMS-WBB. The study results about the thermal properties of SA/CMS-WBB demonstrated that the introduction of copper microspheres could not only improve the thermal conductivity of SA/CMS-WBB, but also could increase the SA loading amount of wheat bran biochar. More importantly, the CMS-WBB could be obtained by only one-step pyrolysis, which greatly simplified the preparation process and saved energy consumption. Furthermore, the raw material of wheat bran is a kind of agricultural waste, which is abundant, cheap and easy to obtain. Hence, the SA/CMS-WBB synthesized in this study had huge potentialities in thermal management applications, and a simplified method for improving the thermal properties of ss-PCMs was provided.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2019
·
IF 4.191
Zhen-xi Zhang,Kai Li,Shan-wei Ma,Min-shu Cui,Qiang Lu,Yong-ping Yang
Phenol is an important phenolic compound widely used in chemical industry. Lignin in lignocellulosic biomass materials has been recognized as a renewable source for phenol production due to its aromatic nature. In the present study, phenol was selectively prepared from fast pyrolysis of biomass using a recyclable magnetic solid base catalyst (K 3 PO 4 /Fe 3 O 4 , MSB) in an atmosphere with low hydrogen content. The study focused on the influence of pyrolysis atmosphere, pyrolysis temperature, catalyst content, and biomass type on the product distribution, as well as the recycle performance of MSB in consecutive pyrolysis experiments. Results suggested that the synergistic effect of MSB catalyst and hydrogen atmosphere significantly improved the formation of phenol. In a hydrogen atmosphere at MSB to biomass ratio of 1, the maximal phenol yield of 4.3 wt% with the selectivity of 17.6% was obtained from poplar wood pyrolysis at 550°C. Pyrolysis experiments with different biomass materials suggested that the phenol formation was positively correlated with biomass lignin content. A three consecutive run experiment indicated that the MSB catalyst had excellent performance on recovery and recycle. In addition, possible synergistic mechanism between MSB and hydrogen atmosphere was proposed.
研究领域:
能源与环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Yijing Ai,Behisht Ara,Baoli Wang,Mansoor Ahmad,Xiao Han,Lisi Wang,Shuhai He,Ruifeng Li,Wei Sun
In this study, a novel one-step synthesis method is proposed for self-supported electrodes by fabricating Fe 3 O 4 loaded three-dimensional graphene through laser-induced pyrolysis (Fe 3 O 4 -LIGE). This electrode offers the advantages including high sensitivity, straightforward manufacturing process, cost-effectiveness, and environmentally benign, making it highly suitable for large-scale industrial production. Subsequently, a portable electrochemical sensor and a flexible supercapacitor were constructed based on Fe 3 O 4 -LIG as active material. The Fe 3 O 4 -LIGE demonstrated a significant increased electrochemically active area for adsorption, coupled with the reduced electron transfer resistance. This combination resulted in an increased number of active sites for the electrochemical reaction. Furthermore, the portable electrochemical sensor based on Fe 3 O 4 -LIGE can be utilized for the sensitive detection of chloramphenicol, which was further applied to the real honey and pork samples with a detection range from 10.0 nmol/L to 5.0 mmol/L and a detection limit of 3.1 n mol/L. Additionally, the flexible supercapacitors constructed from Fe 3 O 4 -LIGE exhibited an excellent reversibility and stability, achieving a specific capacitance of 12.07 mF/cm 2 at a current density of 0.05 mA/cm 2 , which was superior to the capacitance of most previously reported LIG-based devices. In summary, both the electrochemical sensors and the supercapacitors based on Fe 3 O 4 -LIGE demonstrated excellent performances. This innovate and rapid electrode preparation method may pave the way for large-scale fabrication of flexible electronics.
研究领域:
材料科学
·
电化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Qingyang Li,Wenlu Zhang,Yunna Chen,Wenbin Li,Chong He
Large-scale spinning of high-performance SiO2 porous nanofibers remains a pivotal challenge in facilitating their utilization for flexible thermal insulation purposes. Herein, massive spinning of SiO2 porous nanofibers was achieved through the solution blow spinning (SBS) process utilizing microemulsion polysiloxane solutions. Using MK siloxane polymer as the Si source, a solution characterized by high purity and excellent uniformity was obtained. Multicomponent spinnable microemulsion precursor was prepared by incorporating paraffin as the sacrificial phase, Span 80 and Tween 80 as surfactants, and polyvinylpyrrolidone as the spinning aid. Through optimization of the spinnable solution composition and SBS process parameters, high-speed spinning of paraffin/MK precursor nanofibers was accomplished with a rate of 20 mL·h–1. Subsequent high-temperature pyrolysis facilitated the conversion of organic paraffin/MK nanofibers into SiO2 nanofibers with controllable pores structure. Porous SiO2 nanofiber sponges fabricated using the microemulsion SBS technique exhibit distinctive lightweight and thermal insulation properties [0.037 W·(m·K)−1]. These properties promise to facilitate massive spinning of high-performance inorganic fiber sponges for applications in high-temperature thermal management.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Xiangming Hu,Hongbin Wei,Yurui Deng,Zhiyuan Yang,Xiaoxuan Wei,Guoyu Han
As novel advanced organic materials, polyimide aerogels (PI-AER) exhibit high porosity and excellent thermal stability. For the general and safe application of PI-AER, it is imperative to clarify their thermal decomposition process. The kinetic parameters of PI-ARE pyrolysis were calculated using different traditional kinetic methods, and the results showed that the PI-AER pyrolysis process conformed to the Fn-like mechanistic function model with an average activation energy of 143.984 kJ/mol. The pyrolysis mechanism function model of the main pyrolysis stages was optimized and reconstructed to obtain the optimal solution f(α). In addition, the concentration changes of pyrolysis products with increasing temperature were monitored by TG-MS and the PI-AER bond breaking mechanism was analyzed. Finally, the TG curves were fitted piecewise to obtain Ea and lnA for the two pyrolysis processes. Combined with the pyrolysis mechanism and two-stage kinetic parameter analysis, the effects of the two pyrolysis stages of PI-AER on the kinetic parameters were elucidated. It was shown that the activation energies of solvent volatilization and desorption and PI-AER main chain were 60.1 kJ/mol and 147.76 kJ/mol, respectively. This study provides fundamental industrial parameters for the application of polyimide aerogels in extreme conditions.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yi Zhang,Jianhong Lan,Yike Xu,Yuanyuan Yan,Weifeng Liu,Xuguang Liu,Shaonan Gu,Jiadong Zhou,Meiling Wang
Zeolitic imidazolate framework-67 (ZIF-67) has been widely used as a precursor to developing efficient PtCo alloy catalysts for hydrogen evolution reaction (HER). However, traditional in-situ pyrolysis strategies involve complicated interface structure modulating processes between ZIF-67 and Pt precursors, challenging large-scale synthesis. Herein, a “pyrolysis etching-confined pyrolysis” approach is developed to design confined PtCo alloy in porous frameworks of onion carbon derived from ZIF-67. The confined PtCo alloy with Pt content of only 5.39 wt% exhibits a distinct HER activity in both acid (η 10 : 5 mV and Tafel: 9 mV dec −1 ) and basic (η 10 : 33 mV and Tafel: 51 mV dec −1 ) media and a drastic enhancement in stability. Density functional theory calculations reveal that the strong electronic interaction between Pt and Co allows favorable electron redistribution, which affords a favorable hydrogen spillover on PtCo alloy compared with that of pristine Pt(1 1 1). Operational electrochemical impedance spectroscopy demonstrates that the Faraday reaction process is facilitated under acidic conditions, while the transfer of intermediates through the electric double-layer region under alkaline conditions is accelerated. This work not only offers a universal route for high-performance Pt-based alloy catalysts with metal–organic framework (MOF) precursors but also provides experimental evidence for the role of the electric double layer in electrocatalysis reactions.
研究领域:
材料科学
·
电化学
·
催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2026
·
IF 6.5
Xiaolong Chen,Jiayou Sun,Pengcheng Wang,Mingzhou Li,Tomas Ramirez Reina,Jie Yu
This study examines the thermal decomposition kinetics and mechanisms of ethylene-vinyl acetate (EVA) copolymer and Tedlar-polyethylene terephthalate-Tedlar (TPT) laminates. Kinetic parameters were evaluated using the Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods. Pyrolysis experiments for EVA (350-450 °C) and TPT (375-450 °C) were conducted in a fixed-bed reactor and using pyrolysis gas chromatography-mass spectrometry (Py-GC/MS), respectively. In the fixed-bed experiments, the resulting oil products were characterized by gas chromatography-mass spectrometry (GC/MS). EVA exhibited a two-stage thermal decomposition process involving initial deacetylation followed by main chain scission, with an activation energy of 289.12 kJ mol −1 . In the Py-GC/MS experiments, the combination of high temperature (550 °C) and rapid heating caused deacetylation and thermal cracking to occur simultaneously. The resulting unsaturated segments were immediately subjected to thermal cracking, cyclization, and dehydrogenation, yielding primarily 1-olefins, 1,n-dienes, and cycloolefins. In contrast, low temperature slow pyrolysis in the fixed bed reactor favored random scission pathways leading to alkane formation. The pyrolysis of TPT proceeded as a continuous single stage reaction (173.92 kJ mol −1 ), initiated by the dehydrofluorination of polyvinyl fluoride (PVF) with the release of hydrogen fluoride (HF). This process was accompanied by synergistic bond cleavage in polyethylene terephthalate (PET) via a six membered cyclic transition state, yielding benzoic acid, terephthalic acid, and related derivatives. Under high temperature, fast pyrolysis conditions, aromatic compounds such as benzene and naphthalene were increasingly formed through two dominant pathways: decarboxylation of benzoic acid derivatives and cyclization/aromatization of defluorinated conjugated olefins produced during PVF dehydrofluorination. Combustion, driven by oxidative reactions, shifted the thermal decomposition of both EVA (172.29 kJ mol −1 ) and TPT (138.45 kJ mol −1 ) to lower temperatures and introduced an additional char combustion stage.
✓ 已验证
DOI
高影响因子
COMBUSTION SCIENCE AND TECHNOLOGY
·
2021
·
IF 2.174
Heng Yu,Congxue Yao,Yifan Zhou,Jingwen Wang,Wenru Zeng,Lei Song,Xiaowei Mu,Yuan Hu
The thermal decomposition behaviors of corn and its main components have been investigated by applying thermogravimetric analyzer (TGA) under nitrogen atmosphere. As two different simulation methods, the GA (Genetic Algorithm)-based parallel reaction model and linear combination model are proposed in the study, both of which show good agreement with the experimental curves. This indicates that pyrolysis of corn is a process of gradual degradation of its main components. The starch content (64.4%) in corn is much higher than that in other components, and the thermal weight loss caused by starch decomposition is as high as 70%. Moreover, the pyrolysis products of corn and its components were studied by TG-FTIR and TG-GC/MS. The results show that the pyrolysis process of corn is not only the process of independent degradation of its components but also the interaction between different components, which leads to the formation of several new kinds of compounds and the difference in the linear combination model. It provides a reference for the research of grain pyrolysis and gives a model for prediction.
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2023
·
IF 7.5
Bin Hu,Wen-Ming Zhang,Xue-Wen Guo,Ji Liu,Xiao Yang,Qiang Lu
The high percentage of branched units with different structures leads to the complex pyrolysis chemistry and product distribution of hemicellulose. In this study, four main branched monosaccharides, i.e., arabinose (Ara), galactose (Gal), galacturonic acid (GacA), and glucuronic acid (GlcA) were employed as typical xylan-based hemicellulose model compounds. The pyrolysis behaviors and mechanisms of these monosaccharides were deeply explored by the combination of pyrolysis experiments and density functional theory (DFT) calculations. Particularly, the roles of structural differences of these monosaccharides were carefully analyzed. Due to the uronic acid group, GacA and GlcA were easier to decompose, having two weightloss peaks with close intensity, and the release of CO 2 had greater intensity than Ara and Gal pyrolysis at low temperatures. GlcA with the equatorial hydroxyl group can undergo a special C C bond breaking reaction to depart the C6 uronic acid group to release HCOOH. The fast pyrolysis of these monosaccharides obtained similar product species but distinct relative contents. The structure of an uncertain hydromethyl-furnaose product was identified as 5-(hydroxymethyl)furan-3(2 H )-one (5-HMFO) by combined DFT calculations and experimental results. The findings of this work are beneficial to gain a deep understanding of the pyrolysis chemistry of hemicellulose, especially the role of different branches.
研究领域:
生物质能
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）