BIORESOURCE TECHNOLOGY
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2018
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IF 5.807
Xiaoxiao Zhu,Chunyan Li,Jianfa Li,Bin Xie,Jinhong Lü,Yimin Li
For the purpose of producing carbons with developed mesoporosity, a wood biochar was thermally treated at 600–800 °C in the air/nitrogen atmosphere. The mesopore development was observed when the air flux increased to 50–90 mL/min, and the carbon product having high mesopore surface area (316 m 2 /g) and mesopore pore volume (0.284 cm 3 /g) was produced at the treatment temperature of 700 °C. The mesopores were developed mainly in the temperature holding stage of thermal treatment, with size mainly ranged from 20 to 60 Å. The carbons’ adsorption to the antibiotic tetracycline was enhanced by 5.5–9.2 folds when the air/nitrogen mixture was used instead of nitrogen atmosphere in thermal treatment, and the enhanced adsorption is positively related to the mesopore development. In general, this research provides a facile way to produce carbons with developed mesoporosity, so as to improve their adsorption to bulky organic molecules.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Materials Chemistry Frontiers
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2021
·Vol. 5
·期 16
·6101-6113
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IF 6.482
Haikuo Ma,Haoyi Lin,Xiuquan Liu,Hongying Lü,Zhiguo Zhu
Fabricating hierarchical porosity in a metallosilicate zeolite crystal is a facile and efficient approach to increase the accessibility of active sites and to enhance the diffusion performance in the process of catalytic reactions, particularly those involving bulky guest organics. The straightforward and efficient synthesis of hierarchical metallosilicate zeolites was intensively limited by the high-cost mesoporogen, complicated and tedious synthesis procedures, broad mesoporous size distribution, restricted zeolite topologies, and low solid yield. Herein, an innovative hydrothermal synthesis methodology of a hierarchical heteroatom-containing zeolite, in this case of Ti-Beta, via in situ structural reconstruction was proposed. Tetraethylammonium hydroxide (TEAOH) played significant roles of not only as base source, functioning etching effect, but also as structure directing agent (SDA), reconstructing the framework structure in this hydrothermal synthesis. The mesoporosity and Ti4+ species coordinate state could be regulated by varying the TEAOH content, which was closely related to the catalytic activity in oxidative desulfurization. The optimal hierarchical Ti-Beta zeolite with a mesopore size of 7.8 nm and a high solid yield of more than 96% exhibited outstanding catalytic oxidation performance, far outperforming the hydrothermally synthesized Ti-Beta zeolite and postsynthesized Ti-Beta zeolite. This work provides a straightforward and facile methodology for rationally constructing the hierarchical Ti-Beta zeolite, which is promising to be an extension to synthesize other hierarchical heteroatom-containing zeolites without the assistance of a mesoporogen in a short time.
研究领域:
化学工程
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材料科学
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催化
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2023
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IF 7.5
Jiarong Qiu,Ben Zhou,Qiyue Yang,Yi Liu,Liangqing Zhang,Bingshu Wang,Shunming Song,Jingwen Zhang,Suchang Huang,Jianfeng Chen,Lu Lin,Xianhai Zeng
In this study, the acid-base bifunctional magnetic ZrMg@Fe 3 O 4 metallic oxide catalysts with remarkable structural properties were synthesized by the co-precipitation method for the catalytic transfer hydrogenation (CTH) of furfural (FF), ethyl levulinate (EL), and 5-methylfurfural (5-MF) to furfuryl alcohol (FFA), gamma-valerolactone (GVL), and 5-methyl-2-furanmethanol (5-MFA). Characterization results indicated that the ZrMg@Fe 3 O 4 (7: 1:1) catalyst possesses a substantial pore volume, large specific surface area, and mesoporous properties, which play an important role in improving catalytic activity. The leaching experiment indicated that the catalyst was not prone to leaching, proving its structural stability. The yield of FFA, GVL, and 5-MFA could be as high as 92.50%, 95.00%, and 53.95% by optimization experiments. The Py-FTIR, CO 2 -TPD, and poisoning experiments showed that Lewis acid-base sites significantly impact the catalytic activity. The catalyst can be readily isolated and retrieved from the liquid reaction mixture by applying the external magnetic field. The reaction mechanism and catalytic stability were also conducted by systematically studying the reaction experiments and physicochemical properties of the catalyst.
研究领域:
催化
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材料科学
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化学工程
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可持续化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Jingshuang Zhang,He Ding,Yixiao Zhang,Chuan Yu,Peng Bai,Xianghai Guo
Hierarchical aluminosilicate zeolites were simply synthesized by a temperature-gradient strategy using conventional CTAB as single structure directing agent. The as-synthesized zeolites were composed of an ordered two-dimensional hexagonal mesopores and crystallized MFI structure. Catalytic performance of the hierarchical aluminosilicate zeolites were explored by the Claisen-Schmidt condensation of bulky reactants (benzaldehyde and 2′-hydroxyacetophenone). The reaction results showed that the hierarchical zeolites exhibit outstanding catalytic performance with a conversion as high as 73%, which may be attributed to the combined advantage of framework acidity of zeolite and the significantly improved large molecule diffussion in mesoporosity. The higher hydrothermal stability and catalytic stability than those of MCM-41 samples were proved, which were ascribed to the presence of crystallized MFI structure.
研究领域:
化学
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催化
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材料科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Danlong Yang,Yingzhe Liu,Yuling Shi,Qianqian Pan,Yangeng Lan,Jianhong Xu,Tao Wang
Silica aerogel microspheres are known for their unique features which are better than those of the bulk silica aerogel, including excellent biocompatibility and flowability, and have a broader application prospect for biomedicine, adsorption purification, catalytic reactions, energy storage, and sensing. However, the production of high-quality silica aerogel microspheres still poses significant challenges, such as low sphericity, difficult size adjustment, uneven morphology, and a prolonged drying process, especially ambient pressure drying for several hours. Herein, we report a novel process for efficiently synthesizing high-quality silica aerogel microspheres through the use of microfluidic and ambient pressure drying techniques. In the novel process, the colloidal sol microdroplets were prepared in stepped T-microchannels to achieve size adjustment with a narrow diameter distribution and good sphericity. A new drying process under ambient pressure at high temperature was proposed, which realized the rapid drying under ambient pressure for 10 min while the linear shrinkage of the microspheres was less than 5%. Highly spherical and uniform silica aerogel microspheres with diameters adjustable from 50–300 μm were successfully fabricated. The prepared silica aerogel microspheres exhibited high mesoporosity along with ultralow density, high specific surface area, and high hydrophobicity. In addition, the factors that significantly influence the final morphology of the silica aerogel microspheres have been thoroughly researched. This innovative process offers a new approach for the efficient synthesis of high-quality silica aerogel microspheres.
研究领域:
材料科学
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化学工程
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纳米技术
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
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2022
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IF 6.14
Meng Li,Chenxi Liu,Liang Qi,Hongsheng Liu
Hollow-structured nanomaterials, featuring a porous crystalline structure and hollow interior, are conducive to achieving a compartmentalized architecture comprising diverse functional entities. In this study, we have constructed a novel fluorescent enzyme nanocomposite derived from the nanosized hollow ZIF-8 (H-ZIF-8) colloidosomes via a diffusion strategy. Insights into the underlying mechanisms revealed that the diffusion process was driven by mesopore properties and electrostatic interactions. It has also been demonstrated that the molecular sieving property of the colloidosome shell induced an exceptional compartmentalized structure, where nitrogen-doped graphene quantum dots (N-GQDs) were anchored onto the outer surface of the nanosized H-ZIF-8 colloidosomes, whereas glucose oxidase (GOx) was homogeneously encapsulated in the entire cavity. The resultant nanocomposite inherited the mesopore properties of the colloidosome exoskeleton, catalytic ability of GOx, and fluorescence properties of N-GQDs. In particular, the porous properties of the nanosized H-ZIF-8 colloidosomes favored enrichment to target analytes, whereas the compartmentalized GOx and N-GQDs served as a “promoter” (initiate the biochemical reaction) and “signal unit” (intuitive observation) in the glucose probing system, respectively. Furthermore, anchoring N-GQDs onto the outer surface of the nanosized H-ZIF-8 resulted in tailoring of the fluorescence property of the nanocomposite. In the part of glucose sensing, the proposed fluorescence nanosensor could well quantify glucose within a range of 10 to 100 μM with a lower limit of detection of 5.4 μM. This proposed strategy presents opportunities to engineer novel metal–organic framework-based multifunctional nanocomposites and create new applications by combining their unique functions.
研究领域:
材料科学
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纳米技术
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分析化学
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生物传感器
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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）