FUEL
·
2022
·
IF 8.035
Fuwei Li,Xiaofeng Wang,Hengshuo Gu,Hongbing Fu,Asad Ali,Hongfei Lin,Zhixia Li
Minimizing the catalyst cost is critical to achieving long-term economic feasibility for obtaining bio-chemicals directly from biomass. In the present study, low cost ZSM-5 was synthesized via hydrothermal crystallization of the activated aluminosilicate gel without adding any organic ammonium templates and additional seed crystals . The activation process promoted the depolymerization of the silica-alumina species and the formation of active pasty gel containing nucleation precursors, consequently accelerating the subsequent crystallization reaction. The addition of eucalyptus sawdust (ES) in the synthesis process increased the BET (Brunauer-Emmett-Teller) surface area and acidity of the resultant zeolites . The ES-mediated ZSM-5 (AGZ-10) achieved a higher benzene, toluene, ethylbenzene and xylene (BTEX) carbon yield (18.9 %) from co-cracking of ES and waste plastics (WP) (ES/WP mass ratio at 1:1) at 500 °C and exhibited better synergistic effect and anti-coking ability compared to the commercial ZSM-5. The results provide an efficient synthetic strategy to produce low-cost zeolites, and a promising technique to effectively utilize biomass and plastic wastes.
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
NEW CARBON MATERIALS
·
2018
·
IF 1.171
Hai-xiao Yang,He-xiang Han,Ji-tong Wang,Wen-ming Qiao,Li-cheng Ling
Novel high-carbon-yield pitches were prepared through the iodination of 1-methylnaphthalene (1-MNP) followed by dehydroiodination/polycondensation. 1-MNP was first iodinated by I 2 with the aid of I 2 O 5 , yielding mainly 1-iodo-4-MNP. Then, a thermal-dehydroiodination reaction at a comparatively low temperature of 130–180 o C was carried out to condense the iodinated products to obtain the pitches. The structures of the iodinated products and pitches were investigated by TG, GC-MS, 1H-NMR and FT-IR. Results indicated that the iodination selectivity ( S mb) reached 96.4% when 0.75 mol I 2 and 0.18 mol I 2 O 5 reacted with 1 mol 1-MNP at 60 o C for 24 h in acetic acid. Ring-hydrogenation products (tetralin, 5-methyltetralin) and methyl migration products (2-MNP, dimethylnaphthalene and trimethylnaphthalene) were found in the pitches by analyzing their methanol-soluble fractions. Dehydroiodination substantially increased the degree of polymerization and carbon yield of the pitches. The pitches exhibited high polymerization degrees (toluene soluble fraction less than 12 wt%), high carbon yields (54–66 wt%) and complicated 1-MNP molecular assembly patterns including α-α′, α-β′, β-β′, depending on dehydroiodination temperature and time. The iodination/dehydroiodination approach is simple, mild and clean for preparation of high quality pitches for high performance carbon materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Waste and Biomass Valorization
·
2016
·Vol. 9
·期 1
·123-130
·
IF 0.915
Cheng Xu,Tang Yijing,Wang Biao,Jiang Jianming
The utilization of waste rice husks for biochar production has received much attention due to the energy concerns and environmental issues. But how to increase the charcoal yield and quality remains a big challenge. In this work, a two-step pyrolysis of rice husks was carried out at atmospheric pressure, consisting of a first low heating rate step followed by a high heating rate step. The effects of operation conditions at each step, including temperature, heating rate and residence time, on changes in charcoal yield and quality based on fixed-carbon yield were investigated. At the first step, switch temperature and heating rate were the predominant factors that influenced charcoal and fixed-carbon yields. The increase of charcoal and fixed-carbon yields at the first step was attributed to the rate-determined decomposition of hemicellulose. Therefore, the switch temperature should be set at those lower than the decomposition temperature of celluloses. However, at the second step, decreasing final pyrolysis temperature and shortening residence time benefited the increase of charcoal yields. Whereas, a maximum value of fixed-carbon yield was observed at the final pyrolysis temperature of 600 °C, which could result from the aromatics formed from cellulose-derived volatiles. Therefore, the switch temperature should be lower than cellulose decomposition temperature in order to reduce the cycle time for biochar production. Moreover, the charcoal and fixed-carbon yields obtained by the optimized two-step pyrolysis were higher than those by one-step pyrolysis.
研究领域:
能源与环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2020
·
IF 2.87
Tianzhao Hu,Jiafu Chen,Xiaoqing Lu,Jing Chen,Zhimin Chen,Jianwei Fu,Yong Chen
Graphene sheets have a vast number of potential applications due to their excellent properties. However, poor quality and harsh preparation conditions restrict their application. Here, few-layer graphene (FLG) sheet powder with high quality has been synthesized from waste expanded polystyrene (EPS) at low temperature by dense Fe cluster catalysis. The micron-sized FLG sheets comprising about three layers show high crystallinity and good electrical conductivity that are comparable to those of the shear-exfoliated graphene nanoplatelets. More than 70% carbon yield of FLG sheets from cheap EPS and their safe, controllable synthesis conditions make it easy to expand production. The catalytic formation mechanism of FLG sheets is studied.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2025
·
IF 3.3
Shangye Liu,Yongxiang Wang,Lei Jin,Xinru Wang,Chunting Wang,Yushi He,Weimin Zhang
Biomass-derived hard carbon has emerged as a highly promising anode material for sodium-ion batteries (SIBs), owing to its exceptional sodium storage capacity, cost-effectiveness, and sustainable sourcing advantages. However, its widespread commercialization faces significant challenges, including unsatisfactory carbon yield and inadequate rate capability. To address these limitations, this study presents a facile approach to synthesize high-performance soft-hard carbon composites through the strategic combination of pitch and hawthorn seeds. Our research demonstrates that the presence of highly graphitized soft carbon effectively mitigates the inherent drawbacks of hard carbon material. Specifically, the optimized composite with a hawthorn seed-to-pitch mass ratio of 100:10 exhibits superior electrochemical performance compared to pure hawthorn seed-derived hard carbon prepared under identical conditions. The incorporation of pitch-derived soft carbon enhanced the carbon yield from 45.8% to 51.5%. The composite anode delivers a high capacity of 295.9 mAh g-1 (at 20 mA g-1), an outstanding cycling stability (retaining 75.0% capacity retention after 1000 cycles at 500 mA g-1), and significantly enhanced rate capability. Through these studies, we attempted to establish fundamental structure-property relationships and provide valuable guidance for their commercial implementation in SIB systems.
研究领域:
材料科学
·
能源存储
·
生物质利用
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2025
·Vol. 36
·期 9
·e70304
·
IF 3.4
Yong Liu,Jiaming Guo,Zongwei Guo,Lei Shang,Yuhui Ao
The thermal oxidation stabilization process of polyacrylonitrile (PAN) is a violent exothermic reaction process, which is not conducive to the improvement of carbon fiber quality. The highly exothermic reaction was often alleviated by adding unsaturated vinyl carboxylic acid monomers. In this investigation, poly(acrylonitrile-co-2-carboxyethyl acrylate) P(AN-co-CEA) copolymers with varying contents of CEA monomers were synthesized. The effects of CEA on the thermal behavior and structural evolution of copolymers were systematically investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermal gravimetric analyzer (TGA). The results indicated that the introduction of CEA facilitated the cyclization reaction at lower temperatures through the ionic mechanism of the carboxyl group, broadened the exothermic peak, and reduced the heat release rate (Δ H /Δ T ). The activation energies (E a ) decreased from 157.7 KJ/mol for PAN homopolymer to 122.3 KJ/mol for P(AN-co-CEA) copolymer. Moreover, the CEA monomer promoted both the cyclization and dehydrogenation reactions, forming more stable cyclic structures and inhibiting the thermal decomposition of random chain segments. Consequently, higher carbon yield and a greater extent of stabilization (Es) were achieved. Additionally, the combined action of CEA and O 2 jointly enhanced the thermal oxidation stability process, resulting in the formation of oxygen-containing structures and promoting the transition to a graphite-like carbon network. Among the copolymers studied, the composition containing 2 wt% CEA exhibited the most favorable balance in the development of a well-stabilized structure. It was found that the CEA comonomer has the ability to promote the thermal oxidation stabilization process, alleviate the highly exothermic reactions, and reduce the heat release rate. Hence, these findings suggest that P(AN-co-CEA) copolymers have the potential to become carbon fiber precursor materials.
研究领域:
高分子化学
·
材料科学
·
碳材料
·
纤维工程
·
热分析
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 7
·4025-4037
·
IF 5.044
Gao Xiaoru,Yu Yuxiu,He Qian,Li Haojie,Liu Yaodong
A sustainable natural polymer, cellulose, has been used as precursor for producing carbonaceous materials. Ionothermal carbonization (ITC) in ionic liquid (IL) could transform biomass into functional carbon materials at a relatively low temperature. In order to improve the ITC carbon yields and structures, the first raw transition metal chlorides were added into IL, 1-Butyl-3-methyl-imidazole chloride (BmimCl), and their catalyzing effects were compared. It is found that the catalyzing effects of transition metal chlorides are mainly correlated to their cation size. With the addition of 0.5wt% NiCl 2 (based on IL), a high carbon yield of 94wt% is obtained. Additionally, the bio-based carbonaceous materials exhibit a higher graphitization degree with the addition of metal chloride. Furthermore, the IL shows good cyclability, and the carbon yield remains to be higher than 80 wt% after 5 cycles.
研究领域:
材料科学
·
化学工程
·
可持续化学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Yu Kang,Yujia Han,Cong Wei,Kuo Liu,Ming Tian,Chuande Huang,Chaojie Wang,Jian Lin,Baolin Hou,Xiaoli Pan,Yang Su,Lin Li,Riguang Zhang,Yong Hao,Xiaodong Wang
Thermochemical two-step CO 2 splitting is a potential approach that fixes the sustainable resource into transportable liquid fuels. However, the harsh CO 2 splitting conditions, the limited oxygen release kinetics and capacity of metal oxides block further promoted the CO yield and solar-to-fuel energy efficiency. Here, we propose a different carbon cycle assisted by Ni/La 2 O 3 via coupling methane decomposition with thermochemical CO 2 splitting, replacing conventional metal oxides cycle. Superior performance was demonstrated with methane conversion reached around 94% with almost pure H 2 generation. Encouragingly, CO 2 conversion of 98% and CO yield of 6.9 mmol g −1 derived from CO 2 were achieved, with peak CO evolution rate (402 mL min −1 g −1 ) of orders of magnitude higher than that in metal oxide process and outstanding thermodynamic solar-to-fuel energy efficiency (55.5% vs. 18.5%). This was relevant to the synergistic activation of La 2 O 3 and Ni for CO 2 in carbon cycle, thus improving CO 2 splitting reaction with carbon species.
研究领域:
能源化学
·
催化化学
·
可持续能源
·
热化学转化
·
二氧化碳利用
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 19
·48671
·
IF 2.188
Huiqing Wei,Xidong Suo,Chunxiang Lu,Yaodong Liu
The fiber spinning methods determine the formation of the physical structures of polyacrylonitrile (PAN) fibers which further affect stabilization reactions and the mechanical performances of the resultant carbon fibers. In this study, PAN fibers were prepared by both dry-jet gel spinning (g-PAN) and dry-jet wet spinning (w-PAN), and their stabilization behaviors were compared. While the stabilized w-PAN fibers show sheath-core structures, the stabilized g-PAN fibers exhibit relatively uniform stabilized structures along the radial direction. Additionally, the stabilization reactions of g-PAN fibers occur faster than that of w-PAN fibers, and the cyclization, oxidation, and crosslinking reaction activation energies of g-PAN fibers are lower than that of w-PAN fibers, respectively. Moreover, the carbon yield of g-PAN is higher than that of w-PAN fibers. We believe that above changes are possibly ascribed to the formation of different PAN sheath structures and oriented chain structures during dry-jet wet spinning and dry-jet gel spinning. It is concluded that gel spinning could significantly reduce the sheath-core difference of PAN fibers and the stabilized fibers as compared with wet spinning, which leads to a faster stabilization and more uniform stabilized structures. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137 , 48671.
研究领域:
材料科学
·
高分子科学
·
纤维科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2023
·
IF 5.7
Tianli Sun,Ye Wu,Jian Mei,Hang Zhu,Kun Qian,Dong Liu
Using oxygen carrier to relieve uneven mixing of fuel and air under harsh conditions (high temperature and short residence time) is a promising strategy to improve fuel efficiency. In this paper, a range of cerium modified ferric oxide oxygen carriers with excellent redox capability and stability was fabricated to investigate the ethylene rapid oxidation performance and the gas–solid surface reaction of ethylene and iron oxide was studied with density functional theory. The experimental results show that the oxygen carrier with the mole ratio of ferrum : cerium is 9:1 performed the best ethylene oxidation characteristic, because the addition of cerium improved oxygen vacancy capacity to enhance the oxidation for ethylene and its pyrolysis products, which was also confirmed with density functional theory study. Due to the role of both, the ethylene and its pyrolysis products were converted into carbon dioxide and water quickly and effectively (carbon dioxide yield >92%).
研究领域:
化学工程
·
材料科学
·
能源技术
·
催化
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2023
·
IF 9.8
Tan Li,Jing Su,Linjia Yin,Xiangkun Zhang,Cong Wang,Xinbao Li,Jing Zhang,Kaige Wang
A Cu-based catalyst was developed for one-step solvent-free synthesis of aviation biofuel from biomass-derived ketones, including acetone, cyclopentanone, cyclohexanone, and 2-pentanone. Under the optimal working conditions, the conversion rate of acetone, cyclopentanone, cyclohexanone and 2-pentanone of 100% can be achieved by using Cu/Al2O3. 79.7 c% maximum carbon yield of liquid hydrocarbons with 89.5% selectivity of aviation biofuel was obtained under the conditions of 1.0 MPa H2, 280 °C, and 2 h−1 WHSV. The effects of the calcination temperature on the acidity and basicity of the catalyst, as well as the valence and dispersion of Cu species, were investigated. Based on DFT calculations and in situ DRIFTS results, the preferred adsorption of carbonyl groups and efficient dissociation of hydrogen on Cu+ increased the local concentration of H and feedstock on the catalyst surface, accelerating the rate-determining step that predominated on Cu0. The synergistic effect of Cu0 and Cu+ enhanced the formation of aviation biofuel.
研究领域:
催化
·
化学工程
·
可再生能源
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL ENGINEERING
·
2020
·Vol. 146
·期 4
·04020019
·
IF 1.264
Junru Bu,Xinkai Zhou,Huan Liu,Chunmian Lin
The roles of H2O2 in supercritical water oxidation (SCWO) were investigated. The results showed that some of the H2O2 could persist for a short time in SCW, and organic pollutants were mainly oxidized by the O2 generated from the H2O2 in SCWO. However, the introduction of Fe2+ into the SCWO system with H2O2 formed a new Fenton oxidation environment, i.e., supercritical Fenton oxidation (SCFO), which showed the cooperative effect of Fenton oxidation and SCWO. Comparative experiments of phenol and p-aminophenol (PAP) in SCWO and SCFO, respectively, were carried out. The results showed that, in the SCFO system, the CO2 yield from the oxidative degradation of phenol-simulated wastewater (766.0 mg/L) in 45s could reach 73.3%, much higher than that in the SCWO (49.2%) under the same conditions. After 8 min, the CO2 yield in SCFO (97.4%) was also significantly higher than that in SCWO (89.4%). The degradation efficiency of PAP-simulated wastewater (272.5 mg/L) in the SCFO system exceeded 94.3%, especially under acidic conditions, and the degradation efficiency reached 97.4%, much higher than that in the SCWO system (86.2%).
研究领域:
环境工程
·
化学工程
·
水处理技术
·
高级氧化工艺
·
污染控制
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）