Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 10
·1-10
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IF 4.3
Zhao Qiao,Wang Hongyu,Liang Haoting,Han Xiaoxue,Wei Chongyang,Wang Shiwei,Wang Yue,Huang Shouying,Ma Xinbin
Lower olefins, produced from syngas through Fischer-Tropsch synthesis, has been gaining worldwide attention as a non-petroleum route. However, the process demonstrates limited selectivity for target products. Herein, a hybrid catalyst system utilizing Fe-based catalyst and SAPO-34 was shown to enhance the selectivity toward lower olefins. A comprehensive study was conducted to examine the impact of various operating conditions on catalytic performance, such as space velocity, pressure, and temperature, as well as catalyst combinations, including loading pattern, and mass ratio of metal and zeolite. The findings indicated that the addition of SAPO-34 was beneficial for enhancing catalytic activity. Furthermore, compared with AlPO-34 zeolite, the strong-acid site on SAPO-34 was identified to crack the long-chain hydrocarbons, thus contributing to the lower olefin formation. Nevertheless, an excess of strong-acid sites was found to detrimentally impact the selectivity of lower olefins, attributed to the increased aromatization and polymerization of lower olefins. The detailed analysis of a hybrid catalyst in Fischer-Tropsch synthesis provides a practical strategy for improving lower olefins selectivity, and has broader implications for the application of hybrid catalyst in diverse catalytic systems.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Forests
·
2024
·Vol. 15
·期 12
·2262
·
IF 2.4
Luoyuan Zhang,Kuiyan Song
This study aims to enhance the mechanical properties of hot-waxed wood by incorporating microcrystalline cellulose (MCC), thereby addressing the issue of inadequate surface durability. We investigated the effects of varying mass fractions (0%, 5%, 10%, 15%) of MCC on multiple surface properties of hot-waxed wood modified with natural wax and maleic anhydride-ethyl acetate copolymer-grafted Fischer-Tropsch wax. These properties encompass adhesion, hardness, abrasion resistance, impact resistance, surface roughness, gloss, and hydrophobicity. To gain deeper insights into the reinforcing role of MCC, analytical techniques such as Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) were employed to comprehensively characterize the chemical structure, crystalline structure, and surface morphology of the samples. The results reveal that, upon the addition of 5% MCC, the hot-waxed wood treated with modified Fischer-Tropsch wax demonstrates a 41% increase in surface adhesive strength, an improvement in hardness from 2H to 3H, a reduction in surface impact resistance from grade 5 to grade 2, and a 72% decrease in wear mass. Additionally, it exhibits enhanced surface hydrophobicity and thermal stability, while preserving its decorative appearance. These findings endorse the use of MCC in hot-waxed wood, offering significant potential in fields like wooden architecture, indoor wooden decorative panels, and furniture.
研究领域:
材料科学
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木材工程
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 7
·2092-2100
·
IF 5
Yichi Zhang,Ruijue Hu,Haiquan Su,Yue Su
Photothermal catalytic Fischer–Tropsch synthesis (FTS) enhances the catalytic efficiency of thermal-driven FTS reaction using a mild strategy, which is in line with the future trends in the chemical industry. However, constructing catalytic systems with high C5+ product selectivity is a challenge for photothermal FTS, since the hydrocracking reaction involving photogenerated electrons would decrease the long carbon chain product selectivity. In this work, the C5+ product selectivity of FTS was significantly improved from 65% to 93% under photothermal conditions by using heteropoly acid (H3PW12O40) as a catalyst promotor. Further characterization revealed that the enhancement mechanism of the C5+ product selectivity was that the as-designed Co/T-PW catalyst inhibited the hydrocracking reaction involving photoelectrons, promoted carbon chain growth, and directly participated in the cracking of C20+ products. This work provided a simple and efficient strategy to improve the C5+ product selectivity of photothermal FTS, making the photothermal FTS reaction more attractive.
研究领域:
化学工程
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催化科学
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能源转化
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DOI
高影响因子
CLAYS AND CLAY MINERALS
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2023
·Vol. 71
·期 4
·448-460
·
IF 2.2
Qu Hongxiao,Liu Tong,Hu Ruijue,Qu Hao,Zhang Yichi,Yang Hui,Su Haiquan,Su Yue
Modified kaolinites possess excellent adsorption properties and, therefore, are regarded widely as potential catalytic components. The use of modified kaolinites as a catalytic component for Fischer–Tropsch synthesis (FTS) has remained unexplored, however. In the current study, delaminated and pit-rich nano-kaolinite was prepared via acid treatment of N-methylformamide (NMF)-intercalated kaolinite (intercalation-etching strategy), and was used as a support to prepare a cobalt-based FTS catalyst (denoted as 15%-Co-HNKln). Compared with other FTS catalysts, the supports for which were raw kaolinite or directly acid-treated kaolinite, the 15%-Co-HNKln showed several advantages such as large specific surface area, dispersed Co particles with small particle size, more new active sites, and significant surface acidity. Given the aforementioned advantages, the 15%-Co-HNKln catalyst demonstrated very good FTS performance. Compared with that of the raw kaolinite-supported FTS catalyst, the CO conversion rate and C 5 –C 12 hydrocarbon selectivity of 15%-Co-HNKln increased by 20% and 15%, respectively.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
ChemCatChem
·
2017
·Vol. 9
·期 16
·3144-3152
·
IF 4.803
Yong Yuan,Shouying Huang,Hongyu Wang,Yifan Wang,Jian Wang,Jing Lv,Zhenhua Li,Xinbin Ma
Graphical Engineered catalysts : A monodisperse nano-Fe 3 O 4 on α-Al 2 O 3 catalyst synthesized by a novel two-step method of thermal decomposition and impregnation shows enhanced activity and stability for the Fischer–Tropsch synthesis to lower olefins. The effects of promoters (K and S) and size are investigated as well. The Fischer–Tropsch synthesis to lower olefins (FTO) is a desirable nonpetroleum-based route to produce basic chemicals. A novel two-step method was applied to synthesize iron-based supported catalysts, which is to prepare nano-Fe 3 O 4 first by thermal decomposition method and sequentially load them on α-Al 2 O 3 by impregnation. TEM and XRD results manifested that the controllable, uniform Fe 3 O 4 nanoparticles are monodispersed on the surface of α-Al 2 O 3 . H 2 -TPR demonstrated that the reduction of Fe species was facilitated because of the weak interaction between Fe species and the support. These superior properties contribute to an enhanced catalytic activity and stability compared with the catalyst prepared by directly impregnating ammonium iron citrate on α-Al 2 O 3 . Then, the effect of promoters was investigated at the same Fe loading and nanoparticle size. The appropriate addition of K could enhance the catalytic activity and suppress the secondary hydrogenation. On the contrary, S has a negative impact on CO conversion and strongly decreases C 5+ selectivity. Particularly, the combination of K and S could obtain more pronounced CO conversion and higher lower olefins selectivity (≈40 %). Furthermore, size effects were explored by precisely tailoring the iron oxide particle size with the Fe loading kept constant. It was found that 12.0 nm nano-Fe 3 O 4 on α-Al 2 O 3 with or without K plus S promoters showed the best catalytic activity among the catalysts with different particle size.
研究领域:
催化化学
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材料科学
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能源化学
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DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2023
·
IF 5.7
Yanxi Zhao,Shiyan Huang,Chengchao Liu,Yuhua Zhang,Longsheng Wang,Aihua lin,Jinlin Li
Background The design and synthesis of catalysts with high stability, activity and selectivity in Fischer–Tropsch synthesis (FTS) have been attracting extensive research attention. Maintaining high catalytic stability and activity is the best strategy for improving the catalyst efficiency and economic benefits. Methods In this study, graphitic carbon nitride (g-C 3 N 4 )-coated SBA-15 was utilised as a support material to prepare cobalt-based FTS catalysts. The catalysts coated with g-C 3 N 4 were studied via TEM, XPS, XRD, H 2 -TPR, TG, N 2 adsorption–desorption, and tested in a fixed-bed reactor. Significant findings The catalysts coated with g-C 3 N 4 were considerably more stable than the Co/SBA-15 catalyst without g-C 3 N 4 coating during a 100 h test period. Furthermore, the CO-conversion performance of the Co/SBA-15 catalyst decreased continuously. Notably, the activity of the Co/ [email protected] 3 N 4 catalyst with a low g-C 3 N 4 loading was higher than that of the Co/SBA-15@1C 3 N 4 catalyst with a relatively high g-C 3 N 4 loading. g-C 3 N 4 can significantly strengthen the interaction between the cobalt species and the support, thereby increasing the catalyst stability. Therefore, a highly stable catalyst with good activity can be achieved by employing a small amount of g-C 3 N 4 for surface modification. The results highlight the effectiveness of the proposed strategy for preparing highly stable, cobalt-based catalysts with good activity.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2024
·
IF 5.9
Xiao Liu,Xiaolong Zhang,Chunyu Geng,Qinglan Hao,Jie Chang,Xin Hu,Yongwang Li,Botao Teng
Fischer-Tropsch synthesis (FTS) wastewater retaining low-carbon alcohols and acids are organic pollutants as a limiting factor for FTS industrialization. In this work, the structure-capacity relationships between alcohol-acid adsorption and surface species on graphene were reported, shedding light into their intricate interactions. The graphene oxide (GO) and reduced graphene oxide (rGO) were synthesized via improved Hummers method with flake graphite (G). The physicochemical properties of samples were characterized via SEM, XRD, XPS, FT-IR, and Raman. The alcohol-acid adsorption behaviors and adsorption quantities on G, GO, and rGO were measured via theoretical and experimental method. It was revealed that the presence of COOH, C=O and C O species on graphene occupy the adsorption sites and increase the interactions of water with graphene, which are unfavorable for alcohol-acid adsorption. The equilibrium adsorption quantities of alcohols and acids grow in pace with carbon number. The monolayer adsorption occurs on graphene was verified via model fitting. rGO has the highest FTS modeling wastewater adsorption quantity (110 mg/g) due to the reduction of oxygen species. These novel findings provide a foundation for the alcohol-acid wastewater treatment, as well as the design and development of high-performance carbon-based adsorbent materials.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 13
·9243-9253
·
IF 3.9
Shiyong Xing,Xiaofei Liu,Yan Cui,Yuehua Zhao,Ziheng Chen,Sigui Xiang,Minghan Han
Zeolite catalyzed alkylation of benzene with long-chain α-olefins is a promising method for the detergent industry. Considering the long-chain α-olefins from Fischer–Tropsch synthesis always contain some oxygenated organic compounds, the effect of which on the alkylation of benzene with 1-dodecene was comprehensively investigated over beta zeolite herein. n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxygenated organic compounds, and it was revealed that an obvious decrease of lifetime occurred when only trace amount of oxygenated organic compounds were added into the feedstocks. The deactivated catalyst was difficult to regenerate by extraction with hot benzene or coke-burning. A series of characterization tests complementary with DFT calculations revealed that the deactivation was mainly caused by the firm adsorption of oxygenated organic compounds on the acid sites. Further, comparison with the open-framework MWW zeolite revealed a similar effect of oxygenated organic compounds and deactivation mechanism for both beta and MWW, but beta is less sensitive to the oxygenated organic compounds. The main reason lies in the three-dimensional framework of beta, wherein the much higher adsorption energy of 1-dodecene makes it difficult to be replaced by oxygenated organic compounds. Additionally, beta could be regenerated more easily by extraction with hot benzene compared with MWW. But coke-burning caused a sharp decrease of its lifetime, which is mainly due to the decreased acid sites after calcination.
研究领域:
催化化学
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材料科学
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表面科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TENSIDE SURFACTANTS DETERGENTS
·
2022
·Vol. 59
·期 1
·39-50
·
IF 1.058
Fuwen Tan,Xu Li,Jinxiang Dong
Fischer-Tropsch syncrude prepared via the Fischer-Tropsch synthesis (FTS) using a Fe-based catalyst is featured by its high content of linear α-olefins (C 5 –C 13 ). The utilization of C 6 –C 8 α-olefins for the synthesis of alkyl benzene sulfonate surfactants was performed in the present work via dimerization, benzene alkylation, and sulfonation. The effects of the reaction conditions on benzene alkylation over a trimethyl amine hydrochloride-acidic anhydrous aluminum chloride ionic liquid catalyst (Et 3 NHCl-AlCl 3 ) have been studied in detail using C 6 α-olefin dimers as a model alkylation agent. Under the optimal reaction conditions (molar ratio of AlCl 3 to Et 3 NHCl = 2, catalyst loading = 0.29 mol %, reaction temperature = 30 °C, and molar ratio of benzene to C 6 α-olefin dimer = 10) the conversion of the C 6 α-olefin dimer was 100% and the selectivity toward the mono alkylbenzene product was 91.0%. C 6 –C 8 α-olefin dimer alkylbenzene sulfonates (C 6 –C 8 DBS) were synthesized via sulfonation using chlorosulfonic acid and characterized using Fourier Transform Infrared (FT-IR) spectroscopy and Liquid Chromatography–Mass Spectrometry (LC–MS). The surfactant properties of the C 6 –C 8 DBS, including their equilibrium and dynamic surface tension, foaming, wetting and emulsifying capabilities, were closely explored and compared with a commercial linear alkylbenzene sulfonate (LAS). The limiting surface tension ( γ
CMC = 34.62 mN m −1 ) and critical micelle concentration (CMC = 2.15 mmol L −1 ) of C 6 α-olefin dimer alkylbenzene sulfonate (C 6 -DBS) were similar to those of LAS. Upon increasing the hydrocarbon chain length, the γ
CMC of C 6 -DBS, C 7 -DBS, and C 8 -DBS remained unchanged, while the CMC decreased. C 6 –C 8 -DBS exhibited foaming, emulsifying, and wetting properties comparable to LAS.
研究领域:
化学工程
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材料科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2020
·
IF 4.748
Min Wang,Shupeng Guo,Ming Xia,Jungang Wang,Zhongyi Ma,Bo Hou,Litao Jia,Debao Li
Whether Co-ZrO 2 interfacial sites have a beneficial effect on Co-based Fischer-Tropsch synthesis is still controversial. In this paper, different quantities of Co-ZrO 2 interfacial sites were fabricated by changing the impregnation sequence of Zr added to Co/SiC catalysts. The effect of the Co-ZrO 2 interfacial sites was investigated by nitrogen adsorption, X-ray diffraction (XRD), hydrogen chemisorption (H 2 -TPD), temperature-programmed reduction (H 2 -TPR) and TEM-EDS- mapping analyses. It was found that when zirconium was on the surface of cobalt, more Co-ZrO 2 interfacial sites were formed, and a higher selectivity of long-chain hydrocarbons was observed. In addition, the formation of Co-ZrO 2 interfacial sites significantly increased the conversion frequency of CO. This work is of great significance for understanding the role of Co-ZrO 2 interfacial sites and guiding the design of related catalysts in Co-based Fischer-Tropsch synthesis.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2024
·
IF 5.8
Haikun Lang,Fangping Bin,Shuyao Chen,Xiaoli Zhang,Jiuzheng Yin,Jinzeng Pan,Zhandong Wang,Lixia Wei
Fischer–Tropsch synthesis is an important route for the productions of cleaner fuels from non-petroleum materials. Monomethylated alkanes are present in large quantities in Fischer–Tropsch synthetic fuels. However, side-chain position may make a difference in the combustion of the fuels. In this work, the 4-methylheptane (MH4) pyrolysis was investigated experimentally by using a jet-stirred reactor at 800–1125 K and at 760 Torr. Major pyrolysis products, including small molecules and aromatic products, were identified and measured by using the synchrotron ultra-violet photoionization method. Several species were detected and measured, including CH 4 , C 2 H 2 , C 2 H 4 , C 2 H 6 , C 3 H 4 , C 3 H 6 , C 3 H 8 , C 4 H 6 , IC 4 H 8 , C 5 H 6 , C 5 H 8 1-3, C 5 H 10 -2, benzene, naphthalene, indene and C 6 H 5 C 2 H, etc. A detailed kinetic model of MH4 pyrolysis was developed and validated against the experimental results in this work. Rate of production analysis of MH4 indicates that the most significant consumption pathways are H-abstractions. The unimolecular decomposition reactions by the breakages of C C bonds are also important pathways in MH4 consumption. The pyrolysis product distributions of 4-methylheptane, 3-methylheptane and 2-methylheptane were compared to demonstrate the effect of the methyl side chain position on the pyrolysis of those fuels. It is noted that the mole fraction distributions of the smaller species, including CH 4 , C 2 H 2 and C 2 H 6 , are not sensitive to the position of the methyl side-chain, while those of C3-C5 products, including PC 3 H 4 , C 3 H 6 , C 4 H 6 , IC 4 H 8 , C 5 H 8 1-3 and C 5 H 10 -2, are strongly affected. Novelty and significance statement The products of 4-methylheptane pyrolysis were identified and measured by using the synchrotron ultra-violet photoionization method. A detailed kinetic model of 4-methylheptane pyrolysis at atmospheric was constructed for the first time. The consumption pathways of 4-methylheptane pyrolysis were clarified. The effect of methyl side chain position on fuel pyrolysis was analysed. 4-Methylheptane is one of the important branched alkanes in Fischer–Tropsch synthetic diesel fuel. The present work extends the understanding of pyrolysis of long branched alkanes. The results of the study provide guidance in exploring ideal compositions for diesel alternative fuels.
研究领域:
化学工程
·
燃烧科学
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能源科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）