ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Zhenyu Chen,Lu Zhan,Zhenming Xu
Bromine removal is significant in the recycling of waste printed circuit boards (WPCBs). This study found that the critical factors limiting the debromination efficiency of conventional pyrolysis are the formation of coke impeding mass transfer and conversion of bromine into less volatile species, such as coking-Br and copper bromide. According to frontier molecular orbital analysis and thermodynamic equilibrium analysis, C–O bonds of resin are sites prone to electrophilic reactions and copper bromide in residue may undergo hydrolysis; therefore, introducing H2O during pyrolysis was a feasible method for thorough debromination. Through pyrolysis in a water vapor atmosphere, the diffusion limitation of debromination was overcome, and resin was converted into light components; thereby, rapid and deep removal of bromine was achieved. The result indicated that 99.7% of bromine was removed, and the residue could be used as a clean secondary resource. According to life-cycle assessment, pyrolysis of WPCBs in water vapor could be expected to reduce 77 Kt of CO2 emission and increase financial benefits by 60 million dollars, annually.
研究领域:
环境科学
·
化学工程
·
材料科学
·
可持续性
✓ 已验证
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Chunhao Wang,Xiang Xu,Yang Guo,Fan Zhou,Hongyu Chen,Haoyang Li,Zheng Zeng,Liqing Li
The cobalt carbide (Co2C) innovatively prepared from Co–Mn layered double hydroxide (CoMn LDH) has been investigated and evaluated toward its alternative synthesis conditions and different catalytic performances. Along with various characterization techniques, the preparation basically contains four steps (synthesis of CoMn LDH, calcination, reduction, and crystallization) that transform CoMn LDH to CoMn spinel and then to Co2C. Catalyst evaluation toward toluene pyrolysis was conducted. The sample with Co2C exhibited almost 100% conversion rate of toluene, where the resulting hydrogen yield (∼1.8%) is 6 times more than that of the blank test by using silica sand (∼0.3%), realizing the full transfer of hydrogen element from toluene to hydrogen molecule. Furthermore, based on the textural analysis and density functional dispersion correction calculation, which theoretically explained the easy accessibility of toluene to the crystal surface of Co2C(001) with a relatively high adsorption energy (about −280 kJ mol–1), it suggested that Co2C may expand more extensive applications in the field of catalysis.
研究领域:
材料科学
·
催化化学
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DOI
高影响因子
Russian Journal of Physical Chemistry A
·
2022
·Vol. 95
·期 2
·S352
·
IF 0.791
Meng Ying,Lu Shibin,Wu Yaodong,Sun Miao,Lu Haisheng,Zi Zhenfa,Sun Shengjie,Tang Hao
Abstract The porous CoO/MWCNTs and Zn/MWCNTs composites have been fabricated with the wet chemical method and pyrolysis process. For the reason of good impedance matching characteristics, CoO/MWCNTs composites with highly porous structure and dielectric loss properties present exceedingly powerful absorption ability of EM waves, which has a –44.67 dB maximum reflection loss (RL) value at 17.76 GHz at 1.5 mm sample thickness, and the absorption bandwidth below –10 dB is 14.0 GHz (4.0–18 GHz). Moreover, the filling content of the composites into paraffin matrix is merely 10 wt %, which is lower than that of most wave absorbers reported in the past. Consequently, CoO/MWCNTs composites can be used as a potentially lightweight EM wave absorbing material.
研究领域:
材料科学
·
电磁学
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DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2017
·
IF 4.873
Jian-Fei Huang,Qing-Shan Shi,Jin Feng,Ming-Jie Chen,Wen-Ru Li,Liang-Qiu Li
The incorporation of metallic nanoparticles (NPs) into a biomass-based matrix has been intensively investigated because the obtained nanocomposites exhibited effective antibacterial activity to intractable resistance of bacteria. However, the nanocomposites present limitations, such as a multi-step preparation process and a low loading capacity of nanoparticles . A facile preparation route for the preparation of antibacterial metallic nanocomposites would be especially beneficial for industrial fabrication. In this study, we provided a facile strategy for the preparation of a rosin-derived biochar matrix loaded with silver nanoparticles (Ag NPs) as the fillers. The results demonstrated that the preparation of these rosin-derived biochar silver nanocomposites (Rc/Ag nanocomposites) was achieved by a rapid pyrolysis process and a large amount of Ag NPs were in-situ obtained and homogeneously dispersed on the matrix. More importantly, these materials exhibited satisfying antibacterial activities against E. coli and S. aureus. Thus, the Rc/Ag nanocomposites exhibit promising filler for wooden furniture against bacterial infection and could be used as a filter for indoor antibacterial air filtration .
研究领域:
材料科学
·
微生物学
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Lidong Feng,Songyang Feng,Xinchao Bian,Gao Li,Xuesi Chen
In order to obtain the mechanisms of the pyrolysis reaction that poly (lactic acid) (PLA) gives lactide in the presence of Sn, the four types of low molecular weight PLAs (L-PLA) with different end-groups were prepared, including HO-L-PLA-COOH, R-L-PLA-OH, R-L-PLA-COOH, and R-L-PLA-R, and depolymerized by thermogravimetry at different heating rates. As for the pyrolysis reactions of the L-PLAs, their activation energy ( E a ) were estimated by the several isoconversional model-free methods and their kinetic models were also explored by the Malek method. The random degradation behavior of L-PLAs was determined by the plots of ln { − ln [ 1 − ( 1 − w ) 0.5 ] } vs. 1/T for experimental data from TG for L-PLAs and model reactions. The experimental results showed that the E a values and the possible kinetic models for the pyrolysis reactions of the L-PLAs were different due to the different end-groups and thereof the mechanisms for the pyrolysis reactions of PLA that give lactide were proposed under the catalysis of Sn. The pyrolysis reactions of R-L-PLA-OH and R-L-PLA-R trend to be controlled by a single kinetic model. The pyrolysis reactions of HO-L-PLA-COOH and R-L-PLA-COOH are more complex and controlled by not less than two kinetic processes. The pyrolysis reaction of PLA selectively produces lactide through the unzipping and intramolecular transesterification reactions, including the backbiting reaction caused by the Sn-carboxylate and Sn-alkoxide chain ends, which are directly formed from the hydroxyl and carboxyl end-groups of PLA, and the lactide selective elimination at the random position of the polymeric backbone.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
BIOMASS & BIOENERGY
·
2026
·
IF 7
Yanjun Hu,Chong Yang,Fan Yu,Qianqian Guo,Xingxuan Zhang,Wei Bao,Kitae Baek,Rufei Lu,Frederik Ronsse
Co-pyrolysis is an effective way to achieve high-value utilization of biomass and waste plastics. To overcome the limitations of asynchronous heat transfer in traditional co-pyrolysis processes, a ternary molten carbonate system (Li 2 CO 3 –Na 2 CO 3 –K 2 CO 3 ) was used as the reaction medium to study the effects of temperature (450–550 °C) and feedstock ratio (CS:PE = 3:1–1:3) on the co-pyrolysis products of corn stover (CS) and polyethylene (PE) plastic. The molten-salt environment facilitated synchronized decomposition of CS and PE plastic, effectively suppressing polycondensation and coking reactions while promoting hydrodeoxygenation of functional groups and C–O bond cleavage. Moreover, alkaline sites provided by alkali-metal cations catalyzed more complete secondary cracking and reforming of volatiles, resulting in an increase in gas production and a decrease in bio-oil and biochar production. Meanwhile, the fractions of H 2 and CO in the syngas were enriched, the hydrocarbon content in the pyrolysis bio-oil increased, and oxygenated compounds such as alcohols, aldehydes, and ketones were markedly reduced. Additionally, the templating and etching effects of the molten salt improved the structural ordering of the biochar, lowered its O/C ratio, and promoted a transition from microporous to mesoporous architecture. Notably, the synergistic effect between CS and PE was most pronounced at 550 °C with a 1:1 blending ratio, where the H 2 content reached 29.26 vol% (108.11 mL g −1 ) and the hydrocarbon fraction in the bio-oil increased to 62.52%. Overall, molten salt-assisted co-pyrolysis provides a promising strategy for the targeted production of H 2 /CO-rich syngas, low-oxygen bio-oil, and structurally optimized biochar from biomass and waste plastics.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2026
·
IF 8.1
Hankun Lv,Hongsheng Xu,Qiwei Wang,Xu Chang,Weizhao Hu,Lei Song,Fukai Chu,Yuan Hu
Polyethylene (PE) exhibits aggravated fire hazards under sub-atmospheric conditions due to pressure-induced alterations in pyrolysis kinetics and volatile-release behavior. In this work, a pressure-adaptive flame-retardant PE composite was constructed by introducing an MXene-anchored Co 3 O 4 nanohybrid. The FRPE-MXene/Co 3 O 4 composite shows superior flame-retardant and thermal stability compared with other systems. Its total heat release (35.4 MJ/m 2 ) is 46.29% lower than pure FRPE (66.0 MJ/m 2 ). The reduced total CO release (0.77 g), 65.99% increase in residual mass, together with an approximately 20% reduction in smoke density, confirms the enhanced carbonization capability and improved fire safety performance of the material. Moreover, the LOI value reaches 29.6 ± 0.48%, higher than FRPE-MXene (27.1 ± 0.63%) and FRPE-Co 3 O 4 (27.8 ± 0.63%), demonstrating the enhanced flame-retardant efficiency of the hybrid filler system. Microscopic and XPS analyses reveal that the nanohybrid facilitates deeper deoxygenation, enhanced aromatization, and the formation of dense, graphitized char, thereby significantly improving the structural integrity of the condensed phase. Conventional flame-retardant polyethylene exhibits unstable pyrolysis and incomplete oxidation under low-pressure (55 kPa) combustion, leading to excessive hydrocarbon release and poor char formation. SVUV-PIMS analysis shows that introducing the MXene/Co 3 O 4 hybrid system effectively suppresses radical-induced chain scission and enhances char formation, thereby improving combustion stability and flame-retardant efficiency under low pressure. These findings establish a dual catalytic-barrier flame-retardant mechanism, wherein MXene enables efficient heat dissipation and volatile confinement, while Co 3 O 4 promotes redox-driven carbonization. This work provides an effective strategy for designing high-performance flame-retardant polymers suited to low-pressure environments.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2026
·Vol. 37
·期 3
·242
·
IF 2.8
Zhang Jianhua,Li Lu,Hao Rong,Lei Zhipeng,Ma Yun,Li Yuanyuan,Kang Ailiang
CaCu 3 Ti 4 O 12 (CCTO) has been widely studied for capacitor applications due to its excellent giant dielectric constant and frequency stability, but its development is limited by its low breakdown field strength ( E b ). To promote E b and primarily clarify the intrinsic mechanism, a synergistic strategy combining Sr substitution for Ca in CCTO ceramics with the polymer pyrolysis method was adopted. With the increase of Sr substitution, the average grain size of the ceramics gradually decreased and E b was remarkably enhanced. In particular, an E b of 106.0 kV/cm at a current density of 0.05 mA/cm 2 was achieved for Ca 0.4 Sr 0.6 Cu 3 Ti 4 O 12 ceramics, which is mainly attributed to the tremendous increase in grain boundary resistance induced by the increase of grain boundary density and formation of the insulating secondary phase SrO resulting from Sr substitution. We hope this study will provide a potential solution for the fabrication of CCTO-based dielectric ceramics with excellent E b .
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DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2026
·
IF 3.2
Guo Hanxu,Fu Sen,Yuan Hong
Hierarchical zeolites can provide multidimensional spatial networks, thereby holding significant potential as catalysts for BTX production from biomass pyrolysis. In this study, nano-ZSM-5 zeolite (Z X-X ) with a hierarchical pore structure was synthesized using glycine as a growth inhibitor. Due to the exceptional ability of Ni to cleave C–C and C–H bonds, Ni modification was performed on the Z 30-0.2 catalyst. The effects of glycine and Ni loading on the morphology and pore structure of the zeolites were systematically investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N 2 adsorption–desorption. The results demonstrated that the particle size of 10 wt% Ni-Z 30-0.2 zeolite ranged from 200 to 300 nm, with a BET surface area of 314 m 2 /g and abundant mesopores. The NH 3 -TPD results showed that the acid amount of 10 wt% Ni-Z 30-0.2 was 0.72 mmol/g. The prepared zeolite was employed in a fixed-bed reactor to catalyze the pyrolysis of oleic acid for the production of benzene, toluene, and xylene (BTX). The introduction of metal Ni significantly enhanced the BTX yield. At 500 ℃, the average BTX yield achieved with the 10 wt% Ni-Z 30-0.2 catalyst was 19.4 wt%, which was higher than that of the zeolite without Ni loading.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Deyong Che,Liye Wang,Hongpeng Liu,Baizhong Sun,Shuai Guo
Biomass pyrolysis yields fuels and industrial feedstocks but generates large amounts of NO x precursors and is therefore of limited practical use. Herein, we use glutamic acid , histidine , and tyrosine as protein models and palmitic acid as a lipid model to explore the influence of lipids on the emission of NO x precursors during the pyrolysis of protein-rich biomass at various temperatures. The nitrogen-containing components of solid (coke), liquid (tar), and gaseous pyrolysis products were characterized by X-ray photoelectron spectroscopy, gas chromatography-mass spectrometry, and mass spectrometry , respectively, showing that lipids strongly influence the composition of liquid and gaseous products but not that of solid products. The main nitrogenated tar constituents produced in the absence of palmitic acid were identified as heterocycles and amines, whereas amides and nitriles were additionally generated in its presence. The palmitic acid had the most apparent effect on glutamic acid, generating about 34.16% of amides, followed by histidine, which yielded 9.17% amides and only 4.25% of tyrosine. Thus, our results indicate that the pyrolytic generation of NO x precursors from lipid-rich biomass such as sludge can be reduced by optimizing pyrolysis temperature and providing guidance for developing biomass pyrolysis technologies.
研究领域:
生物质能
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY A
·
2016
·
IF 2.883
Olivier Herbinet,Anne Rodriguez,Benoit Husson,Frédérique Battin-Leclerc,Zhandong Wang,Zhanjun Cheng,Fei Qi
The thermal decomposition of cyclopentene was studied in a jet-stirred reactor operated at constant pressure and temperature to provide new experimental information about the formation of the first aromatic rings from cyclic C5 species. Experiments were carried out at a residence time of 1 s, a pressure of 106.7 kPa, temperatures ranging from 773 to 1073 K and under diluted conditions (cyclopentene inlet mole fraction of 0.04). Species were quantified using three analytical methods: gas chromatography, synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS), and single photon laser ionization mass spectrometry (SPI-MS). Several species could be quantified using both methods allowing comparison of experimental data obtained with the three apparatuses. Discrepancies observed in mole fraction profiles of some large aromatics suggest that the direct sampling in the gas phase (with a molecular beam or a capillary tube) provide more reliable results. The main reaction products are 1,3-cyclopentadiene and hydrogen. The formation of many unsaturated C2–C6 olefins, diolefins and alkynes was also observed but in smaller amounts. Benzene, toluene, styrene, indene, and naphthalene were detected from 923 K. SVUV-PIMS data allowed the identification of another C6H6 isomer which is 1,5-hexadien-3-yne rather than fulvene. The quantification of the cyclopentadienyl radical was obtained from SVUV-PIMS and SPI-MS data with some uncertainty induced by the possible contribution to the signal for m/z 65 of a fragment from the decomposition of a larger ion. This is the first time that a radical is quantified in a jet-stirred reactor using non-optical techniques. SPI-MS analyses allowed the detection of species likely being combination products of allyl and cyclopentadienyl radicals. A model was developed for the pyrolysis of cyclopentene. This model includes routes of formation of aromatics from the cyclopentadienyl radical. The comparison of experimental and computed data is overall satisfactory for primary reaction products whereas discrepancies are still observed for aromatics.
研究领域:
燃烧化学
·
物理化学
·
反应动力学
·
质谱分析
·
烃类热解
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Hongdi Yu,Fawei Lin,Xuan Guo,Chujun Luan,Eslam Salama,Mona Ossman,Xinghua Liu,Rundong Li,Jiantao Li,Lei Che,Wangyang Tian,Beibei Yan,Guanyi Chen
Pyrolysis of oily sludge (OS) possesses dual advantages of oil recovery and harmless treatment. Exploring the reaction pathway for petroleum hydrocarbons during pyrolysis in the presence of minerals is critical for optimizing pyrolysis parameters. This study selected six pure soil minerals and five typical oil compounds as representative to simulate OS samples. Model compounds are more helpful deriving and clarifying the internal mechanism. The mixed oil compounds were continuously loading fed into reactor loaded with varied minerals, which was facilitated the detection of pyrolytic products. Meanwhile, the pyrolysis reaction pathways of oil compounds at different temperature and pressure were simulated by ReaxFF MD. According to the experimental results, high temperature increased the content of light hydrocarbons and gas products (i.e., C 3 H 4 , C 4 H 8 , CH 4 , and H 2 ). Montmorillonite (MT) and illite (IT) exhibited catalytic ring-opening and cracking effects as alkaline minerals, while the kaolin (KL) presented catalytic aromatization effects. The catalytic ring-opening effect of calcite (CA) and hematite (MA) was equally evident, but quartz (QA) possessed a weak catalytic effect and even promoted condensation . n-Dodecane (ND) and 1-dodecene (1-DE) had more complicated pathways compared to other com-pounds with stable rings. The main cracking reaction pathway of ND was the breakage of β C C bond, and the C C bond at both ends was easier to break than the one in the middle. The pyrolysis reaction pathway of 1-DE not only included the breakage of β C C bond, and the generation of ethyl radicals. The methyl groups in methylcyclohexane (MC), methylbenzene (MB), and 1-methylnaphthalene (1-ME) could be detached, while ring-opening reactions generated free radicals . This work provides detailed explanation of pyrolysis reaction pathway of oil compounds and the catalytic mechanism of soil minerals, which helps us understand OS pyrolysis process.
研究领域:
环境化学
·
能源工程
·
石油污染治理
·
热解机理
·
计算化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）