INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Xizhuang Qin,Tao Shen,Guanbo Li,Lei Shi,Zhenyu Liu,Qingya Liu
In order to obtain chemically meaningful and extendable kinetics for direct coal liquefaction (DCL) the experimental coal conversion ( X C ) and oil yield ( Y O ) are correlated with coal constituents and the conditions. The coal is assumed to have three constituents mimicking its maceral constituents liptinite, vitrinite and inertinite. The quantities of them are estimated based on the TG curve of coal, and correlated with the X C and Y O by non-linear regression. For Naomaohu (NMH) coal that is dominant with the vitrinite and Shangwan (SW) coal that has similar contents of vitrinite and inertinite, the three-constituent kinetics model is significantly better than that of traditional single-component kinetics model that requires the regression-determined maximum conversion X C,M and maximum oil yield Y O,M . The k 1 for the vitrinite-like component a 1 is always much larger than k 2 for the inertinite-like component a 2, and k 1 usually shows a better relationship with 1/T than k 2 . The E a of NMH for X C and Y O are close to each other, suggesting a high content of weak bonds in the structure; whereas the E a of SW for Y O is significantly larger than that of X C , suggesting that many oil originates from the secondary reaction rather than the primary covalent bond cleavage.
研究领域:
化学工程
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能源科学
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DOI
高影响因子
FUEL
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2024
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IF 6.7
Caige Wang,Tao Wang,Qian Liu,Dongling Wu
The development of catalytic pyrolysis strategy is the key to the efficient utilization of raw coal. Herein, a novel microwave-assisted deep eutectic solvent (DES) swelling strategy was used to catalyze the pyrolysis of Naomaohu coal. The multifunctional FeCl 3 -Levulinic acid DES was synthesized, it could not only act as the solvent to swell coal, but to highly efficient catalyzed the pyrolysis of the swelled coal. During the process of microwave swelling, DES enhanced the induced polarization of unsaturated bonds, destroyed the weak intermolecular chemical bonds, increased the spacing of aromatic layers and reduced the particle size of raw coal, thus exhibiting a superior swelling effect. Notably, with the catalytic action of DES, it effectively promoted the conversion of coal as well as the escape of light components in the pyrolysis process. Based on the advantages of DES, the pyrolysis tar yield increased significantly (from 11.85% to 17.63%) and the yield of Benzene-Toluene-Xylene was as high as 11.31% in the tar and its content was 14.48 mg g −1 . The light component (BP ≤ 360 °C, 67.50%) and light oil (BP ≤ 170 °C, 42.00%) of the tar reached high levels. What’s more, the pyrolysis behavior and kinetics results indicated that the pre-exponential factor was 2.61 × 10 16 min −1 and the average apparent activation energy was 267.39 kJ mol −1 . The proposed efficient method is expected to provide novel strategy for the swell and catalytic pyrolysis of raw coal using diverse multifunctional DES.
研究领域:
能源科学
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化学工程
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DOI
高影响因子
JOURNAL OF CATALYSIS
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2018
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IF 6.759
Meng Pan,Jiajun Zheng,Yujian Liu,Weiwei Ning,Huiping Tian,Ruifeng Li
The conversion of the heavy fractions of crude oil into transportation fuels and chemical feedstocks is still a severe challenge for fluid catalytic cracking (FCC) technology, in which geometrical parameters of the catalyst are of key importance to the accessibility for reactant and product molecules to travel through the pore space. Here a new core-shell zeolite catalyst with hierarchical pore network from macro- via meso- to micropores is developed by controlling overgrowth of another zeolite shell on the surface of a commercial Y-zeolite. The zeolite shell is a distinctive nano ZSM-5 crystals. The core-shell zeolite catalyst has a high thermal and hydrothermal stability because of high crystallinity, which can meet the industrial requirements. More importantly, the heavy oil can be cracked by the designed zeolite catalyst step-by-step into the required products. The meso- and macroporous shell facilitates pre-cracking the large molecules in heavy oil into moderate ones which can directly diffuse into the micropores of the Y-zeolite to be cracked selectively into the desired products. Both the pore structure network and acid sites distribution of the core-shell zeolite catalyst in the FCC processing are completely harmonious. As a practical example, the catalytic cracking of VGO heavy oil is actualized over the new catalyst. The results showed that the conversion of heavy oil and the yield of gasoline increased by 1.8 wt% and 8.9 wt% respectively, LPG decreased by 6.9 wt%, iso -paraffins and olefins in gasoline fraction increased by 5.21 wt% and 6.31 wt% respectively, aromatics decreased by 11.55 wt%, because of the graduated cracking in core-shell zeolite and returned isomerization in nano ZSM-5, compared with commercially industrial FCC catalyst.
研究领域:
化学工程
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催化材料
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石油加工
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2022
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IF 11.889
Chao Liu,Bingyang Liu,Xing Wang,Zhanghong Xie,Lili Tong,Xiangchen Kong,Yuyang Fan,Rui Xiao
Tandem strategy for lignin utilization with photocatalytic preoxidation and ultrasonic cavitation depolymerization was proposed. Cornstalk residual lignin from industrial bioethanol process was first photocatalytically preoxidized under visible light by g -C 3 N 4 and WO 3 / g -C 3 N 4 / h -BN (WCB) photocatalysts respectively, then obtained lignin samples were characterized to confirm the preoxidation with raw lignin as a blank. During photocatalytic preoxidation, benzyl hydroxyls in lignin was transformed to carbonyls, but a certain degree of lignin degradation and condensation was observed. In comparison, WCB-catalyzed photopreoxidation was more effective. Thereafter, lignin depolymerization was achieved by ultrasonic cavitation-assisted ethanololysis under optimal conditions. Compared with the mere ultrasonic cavitation depolymerization of pristine lignin, WCB-induced photocatalytic preoxidation improved the conversion rate by 14%, the light-oil yield by 26%, and the phenolic monomer yield by 35%. In general, the reported tandem method worked very well for the enhancement of lignin depolymerization and provided a new idea for the development of lignin valorization.
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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DOI
PubMed
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2025
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IF 6.2
Wenyuan Duan,Shaoquan Chen,Jiale Lu,Yutong Li,Miaomiao Li,Jianjing Gao,Yuzhen Zhao
Lignin, an abundant byproduct of lignocellulosic biorefineries, exhibits significant potential as a renewable feedstock for the production of value-added aromatic chemicals and high-energy-density biofuels due to its complex, highly aromatic polymeric structure. In this study, we investigated the effect of a Co-loaded HZSM-5 (50) (HZ) catalyst on oxidative valorization of kraft lignin under mild conditions of air. The bio-oil yield was increased with the increasing loading of Co, and was obtained to be 45.3 wt.% at 140°C/ 30 min. The desilication of zeolite exhibited a promising impact on the depolymerization of lignin, and the bio-oil was significantly enhanced to 51.8 wt.% with 10Co/HZ-n catalyst. Herein. The effect of metal promoters (Zn, Fe, and Nb) were also comprehensively determined by their successive loading on 10Co/HZ-n catalyst. The maximum bio-oil yield (67.3 wt.%) was evaluated with 10Co-3Nb/HZ-n catalyst at 120°C/ 30 min, reaction conditions. Additionally, the reusability performance of the 10Co-3Nb/HZ-n catalyst was examined for up to four catalytic cycles. The elemental analysis of bio-oils showed a significant improvement in the quality in terms of high calorific value (36.8 MJ/kg) for the 10Co-3Nb/HZ-n. Additionally, vanillin (68.2%) was observed as the main selective catalytic product, and its maximum selectivity was also determined for the optimum 10Co-3Nb/HZ-n bio-oil. The study emphasises the role of high metal valent ions in the selective fractionation of lignin into valuable phenolic compounds.
研究领域:
催化
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生物质转化
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绿色化学
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可再生能源
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高分子降解
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化学工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）