Microporous and Mesoporous Materials最新文献_第7页

Effective cryosorption of trace levels of hydrogen isotopologues on MS 13X zeolite: Implications for fusion fuel cycle applications

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-18 DOI: 10.1016/j.micromeso.2024.113464

V. Gayathri Devi , Aravamudan Kannan , Deepak Yadav , Pragnesh B. Dhorajiya , Rajendra P. Bhattacharya , Amit Sircar

Cryogenic adsorption is a promising technology for removing trace levels of hydrogen isotopologues (H₂, HT, D₂ and T₂) from helium purge gas in the breeder zone of a fusion reactor. While Zeolites 4A and 5A are commonly used in packed bed cryogenic adsorption systems, MS 13X zeolite, despite its larger surface area and pore volume, has been less explored for adsorbing hydrogen isotopes. This study discusses the development of the lab scale cryogenic molecular sieve bed (CMSB) system and experimentally investigates the adsorption of hydrogen (H₂) - deuterium (D₂) on MS 13X zeolite at 77.4 K. From the breakthrough experiments, the adsorption capacity at bed saturation for the single-component system containing 1000 ppm of H₂ is 0.101 mol/kg, while that for 1000 ppm D₂ is 0.243 mol/kg. For a binary mixture with 1000 ppm each of H₂ and D₂ in helium gas, the observed saturation capacities are 0.1 mol/kg and 0.237 mol/kg for H₂ and D₂, respectively with an isotopic selectivity of 2.1 for D₂ over H₂. Considering the challenging as well as hazardous nature of experiments with radioactive isotopes, a numerical model employing the extended Langmuir dual-site and linear driving force model is implemented to simulate the binary and ternary breakthrough curves for various hydrogen isotopologues mixtures in He gas that are relevant to fusion fuel cycle system. Analysis reveals the reduced separability of the H₂-HT mixture when compared to H₂-D₂, and this may be linked to the difference in the respective binary pair's zero-point energies. At 77.4 K, a maximum selectivity of 4 is observed through simulations for T₂ over H₂ at equimolar partial pressures of 10 Pa in helium gas on MS 13X zeolites. A comparative evaluation of commercial LTA and MS 13X zeolite beads reveals that MS 13X exhibits performance that is intermediate to LTA 4A and LTA 5A under identical experimental conditions. This study demonstrates that MS 13X zeolite may be gainfully deployed for the cryosorption of low concentrations of hydrogen isotopes in a continuously flowing He gas.

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引用次数: 0

Assessing the efficiency of zeolites in BTEX adsorption: Impact of pore structure and humidity in single and multicomponent systems

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-17 DOI: 10.1016/j.micromeso.2024.113462

Maria Luisa Feo , Massimiliano Frattoni , Ester Paoloacci , Maria Masiello , Giulio Esposito , Rafael Gonzalez-Olmos , Emanuela Tempesta , Francesca Trapasso , Emiliano Zampetti , Marco Torre , Ettore Guerriero , Valerio Paolini

Among volatile organic compounds (VOCs), benzene, toluene, ethylbenzene and o-xylene (BTEX) have attracted global attention because of their high toxicity to the environment and human health. Adsorption is considered one of the most efficient, simple and low-cost technology for VOC pollution control and zeolites have been commonly used as adsorbent for this purpose. However, the evaluation of the performance of zeolites in the adsorption of BTEX under realistic conditions such as the presence of humidity or multicomponent systems has been poorly addressed. In this study, the adsorption capacity of BTEX of seven zeolites belonging to the structural families LTA, MFI, BETA, MOR and FAU have been investigated. Zeolites have been characterized by X-ray fluorescence and nitrogen sorption measurements. The relationship between the adsorption capacity and physicochemical parameters was investigated. It was found that MFI structure was the best adsorbent for benzene and toluene reaching an adsorption capacity of 69.2 mg/g. Whereas FAU structure exhibited preference to trap ethylbenzene and o-xylene adsorbing up to 93.8 mg/g. Specific surface area and pore diameter of zeolites were found to be the most important parameter for BTEX adsorption. The properties of the adsorbate (molecular structure, polarity and boiling point) played also a key role in adsorption.

Si/Al ratio was a key factor in determining adsorption performance under humidity conditions with the best adsorption capacity reaching 16.9 mg/g. In multi-component system, the adsorption capacity of zeolites decreased more than 14 %. The results obtained may guide to select proper adsorbent for BTEX in real applications.

{"title":"Assessing the efficiency of zeolites in BTEX adsorption: Impact of pore structure and humidity in single and multicomponent systems","authors":"Maria Luisa Feo , Massimiliano Frattoni , Ester Paoloacci , Maria Masiello , Giulio Esposito , Rafael Gonzalez-Olmos , Emanuela Tempesta , Francesca Trapasso , Emiliano Zampetti , Marco Torre , Ettore Guerriero , Valerio Paolini","doi":"10.1016/j.micromeso.2024.113462","DOIUrl":"10.1016/j.micromeso.2024.113462","url":null,"abstract":"<div><div>Among volatile organic compounds (VOCs), benzene, toluene, ethylbenzene and <em>o</em>-xylene (BTEX) have attracted global attention because of their high toxicity to the environment and human health. Adsorption is considered one of the most efficient, simple and low-cost technology for VOC pollution control and zeolites have been commonly used as adsorbent for this purpose. However, the evaluation of the performance of zeolites in the adsorption of BTEX under realistic conditions such as the presence of humidity or multicomponent systems has been poorly addressed. In this study, the adsorption capacity of BTEX of seven zeolites belonging to the structural families LTA, MFI, BETA, MOR and FAU have been investigated. Zeolites have been characterized by X-ray fluorescence and nitrogen sorption measurements. The relationship between the adsorption capacity and physicochemical parameters was investigated. It was found that MFI structure was the best adsorbent for benzene and toluene reaching an adsorption capacity of 69.2 mg/g. Whereas FAU structure exhibited preference to trap ethylbenzene and <em>o</em>-xylene adsorbing up to 93.8 mg/g. Specific surface area and pore diameter of zeolites were found to be the most important parameter for BTEX adsorption. The properties of the adsorbate (molecular structure, polarity and boiling point) played also a key role in adsorption.</div><div>Si/Al ratio was a key factor in determining adsorption performance under humidity conditions with the best adsorption capacity reaching 16.9 mg/g. In multi-component system, the adsorption capacity of zeolites decreased more than 14 %. The results obtained may guide to select proper adsorbent for BTEX in real applications.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113462"},"PeriodicalIF":4.8,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of ZSM-5 from natural mordenite from Spain

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-17 DOI: 10.1016/j.micromeso.2024.113463

Yaregal Awoke , Manuel Sánchez-Sánchez , Itziar Arnaiz , Isabel Diaz

Zeolite ZSM-5 has been synthesized using natural mordenite sourced from the San José-Los Escullos-Cabo de Gata deposit in southeast of Spain. The final pure ZSM-5 was achieved without the need of calcination of the natural mordenite through an inter-zeolite transformation being the adjustment of the Si/Al ratio the key factor. The Si/Al ratio of the natural mordenite was modified through two main methods: (i) dealumination under acidic conditions and (ii) the addition of an extra silica source. Dealumination process adds the advantage of eliminating the impurities present in the initial natural mordenite. ZSM-5 with over 88 % crystallinity was produced under hydrothermal synthesis conditions at 190 °C for 48 h using NH₄OH as the alkalinity source with coffin shape particles showing short b-axis ranging from 90 to 200 nm. Similarly, ZSM-5 with over 78 % crystallinity was obtained with NaOH as the alkalinity source at 190 °C for 48 h, however, the particles are irregular-shaped of around 160–260 nm in size. In the second approach, despite the presence of impurities of Fe, highly crystalline (over 100 % crystallinity) ZSM-5 is produced, once again with well-shaped coffin shaped crystals using NH₄OH yet larger, with a b-axis ranging from 200 to 300 nm and irregular shaped ZSM-5 using NaOH.

{"title":"Synthesis of ZSM-5 from natural mordenite from Spain","authors":"Yaregal Awoke , Manuel Sánchez-Sánchez , Itziar Arnaiz , Isabel Diaz","doi":"10.1016/j.micromeso.2024.113463","DOIUrl":"10.1016/j.micromeso.2024.113463","url":null,"abstract":"<div><div>Zeolite ZSM-5 has been synthesized using natural mordenite sourced from the San José-Los Escullos-Cabo de Gata deposit in southeast of Spain. The final pure ZSM-5 was achieved without the need of calcination of the natural mordenite through an inter-zeolite transformation being the adjustment of the Si/Al ratio the key factor. The Si/Al ratio of the natural mordenite was modified through two main methods: (i) dealumination under acidic conditions and (ii) the addition of an extra silica source. Dealumination process adds the advantage of eliminating the impurities present in the initial natural mordenite. ZSM-5 with over 88 % crystallinity was produced under hydrothermal synthesis conditions at 190 °C for 48 h using NH<sub>4</sub>OH as the alkalinity source with coffin shape particles showing short <em>b</em>-axis ranging from 90 to 200 nm. Similarly, ZSM-5 with over 78 % crystallinity was obtained with NaOH as the alkalinity source at 190 °C for 48 h, however, the particles are irregular-shaped of around 160–260 nm in size. In the second approach, despite the presence of impurities of Fe, highly crystalline (over 100 % crystallinity) ZSM-5 is produced, once again with well-shaped coffin shaped crystals using NH<sub>4</sub>OH yet larger, with a <em>b</em>-axis ranging from 200 to 300 nm and irregular shaped ZSM-5 using NaOH.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"385 ","pages":"Article 113463"},"PeriodicalIF":4.8,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of mesoporous alumina through a three-compartment electrodialysis method

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-15 DOI: 10.1016/j.micromeso.2024.113460

Ya-Dong Xie, Wen-Cui Li, Hao-Wei Wang, An-Hui Lu

Alumina has attracted considerable interest due to its catalytic and adsorptive properties. Although sodium aluminate hydrolysis is the traditional method of synthesizing alumina, its production often contains impurities that limit its application. Herein, we propose a novel and environmentally friendly approach for synthesizing mesoporous alumina using a three-compartment electrodialysis system with sodium aluminate as the precursor. By employing selectively permeable anionic membranes, we successfully synthesized mesoporous alumina with a purity of 99.9 %. The experimental results elucidated that aluminate ion transport kinetics were markedly accelerated under the synergistic effects of elevated feed concentration, decreased pH, and heightened applied voltage, a phenomenon predominantly governed by the consequent reduction in membrane resistance. The resultant mesoporous alumina exhibited a pore size of 30 nm and a pore volume of 1.80 cm³ g⁻¹. This work introduces an innovative method for mesoporous alumina synthesis via a three-compartment electrodialysis system, paving the way for novel applications in various engineering fields.

{"title":"Synthesis of mesoporous alumina through a three-compartment electrodialysis method","authors":"Ya-Dong Xie, Wen-Cui Li, Hao-Wei Wang, An-Hui Lu","doi":"10.1016/j.micromeso.2024.113460","DOIUrl":"10.1016/j.micromeso.2024.113460","url":null,"abstract":"<div><div>Alumina has attracted considerable interest due to its catalytic and adsorptive properties. Although sodium aluminate hydrolysis is the traditional method of synthesizing alumina, its production often contains impurities that limit its application. Herein, we propose a novel and environmentally friendly approach for synthesizing mesoporous alumina using a three-compartment electrodialysis system with sodium aluminate as the precursor. By employing selectively permeable anionic membranes, we successfully synthesized mesoporous alumina with a purity of 99.9 %. The experimental results elucidated that aluminate ion transport kinetics were markedly accelerated under the synergistic effects of elevated feed concentration, decreased pH, and heightened applied voltage, a phenomenon predominantly governed by the consequent reduction in membrane resistance. The resultant mesoporous alumina exhibited a pore size of 30 nm and a pore volume of 1.80 cm<sup>3</sup> g<sup>−1</sup>. This work introduces an innovative method for mesoporous alumina synthesis via a three-compartment electrodialysis system, paving the way for novel applications in various engineering fields.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113460"},"PeriodicalIF":4.8,"publicationDate":"2024-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Intrusion-extrusion of water into-from hydrophobic nanopores at high temperature: Unexpected dependence of dewetting pressure above 200 °C

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-15 DOI: 10.1016/j.micromeso.2024.113461

Cléophée Gourmand , Luis Bartolomé , Eder Amayuelas , Juan Miguel López del Amo , Elena Palomo del Barrio , Simone Meloni , Yaroslav Grosu

Wetting of a porous solid by a fluid is of significant interest to many industrial processes. However, at the nanoscale, this process is complex, and little is known about its temperature dependance. In this work, we explored the intrusion-extrusion of water for a heterogeneous lyophobic system composed of a hydrophobic mesoporous silica gel and water over a wide 25–250 °C temperature range. The intrusion pressure was found to have a classical negative temperature dependance in the whole 25–250 °C temperature range. However, an unexpected non-monotonic temperature dependance was observed for the extrusion pressure. In particular, it became temperature independent above 200 °C. This observation suggests that dewetting of nanopores at high temperature is more complex than previously thought of and serves as experimental grounds for further theoretical exploration.

引用次数: 0

Boron's role in altering MFI-type zeolite

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-14 DOI: 10.1016/j.micromeso.2024.113454

Vladislav Rac , Vesna Rakić , Ana Palčić , Eddy Dib , Georgeta Postole , Ljiljana Damjanović-Vasilić , Vladimir Pavlović , Steva Lević , Sanja Bosnar

All-silica, boron and boron-aluminium substituted MFI-type zeolites were prepared. Different amounts of boron were added to the starting reaction mixtures to investigate their influence on the properties of the obtained zeolites. A comprehensive characterization of the materials was conducted using various techniques: X-ray Diffraction (XRD), nitrogen physisorption, Scanning Electron Microscopy (SEM), infrared (IR), Nuclear Magnetic Resonance (NMR) spectroscopy, thermogravimetric analysis (TGA) as well as microcalorimetry. The MFI topology and crystallinity is preserved regardless the amount of heteroatoms that occupied different local environments, while the morphology of the crystals, their thermal stability, and their acidity differ considerably. For instance, boron assuming both tetrahedral and trigonal coordination, affect the interactions of the framework with both the organic structure directing agents (OSDA) and ammonia species giving rise to detectable differences in acidity.

{"title":"Boron's role in altering MFI-type zeolite","authors":"Vladislav Rac , Vesna Rakić , Ana Palčić , Eddy Dib , Georgeta Postole , Ljiljana Damjanović-Vasilić , Vladimir Pavlović , Steva Lević , Sanja Bosnar","doi":"10.1016/j.micromeso.2024.113454","DOIUrl":"10.1016/j.micromeso.2024.113454","url":null,"abstract":"<div><div>All-silica, boron and boron-aluminium substituted MFI-type zeolites were prepared. Different amounts of boron were added to the starting reaction mixtures to investigate their influence on the properties of the obtained zeolites. A comprehensive characterization of the materials was conducted using various techniques: X-ray Diffraction (XRD), nitrogen physisorption, Scanning Electron Microscopy (SEM), infrared (IR), Nuclear Magnetic Resonance (NMR) spectroscopy, thermogravimetric analysis (TGA) as well as microcalorimetry. The MFI topology and crystallinity is preserved regardless the amount of heteroatoms that occupied different local environments, while the morphology of the crystals, their thermal stability, and their acidity differ considerably. For instance, boron assuming both tetrahedral and trigonal coordination, affect the interactions of the framework with both the organic structure directing agents (OSDA) and ammonia species giving rise to detectable differences in acidity.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113454"},"PeriodicalIF":4.8,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of anionic species on the crystallization and aluminum localization in the zeolite framework

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-14 DOI: 10.1016/j.micromeso.2024.113456

Liang Zhao , Yong Wang , Peipei Xiao , Hiroto Toyoda , Qi Li , Yuqin Sun , Bekhti Samya , Hermann Gies , Toshiyuki Yokoi

The distribution of acid sites, which are derived from tetrahedrally coordinated aluminum (Al) atoms within zeolite framework plays a critical role in the acidic catalyzed reactions, is strongly influenced by electrostatic interactions between cationic structure-directing agents (SDAs) and anionic charges. Herein, we synthesized various ZSM-5 zeolites without OSDAs and conducted an in-situ analysis to investigate the impact of anionic species from various Al sources on the crystallization and acid site localization in the framework. The results demonstrated that when Al(NO₃)₃ is used as the Al source (denoted as Z5-N), the electronic environment influenced by NO₃⁻ alters the framework formation pathway, leading to the creation of distorted, tetracoordinated Al intermediates. This process enhances Al atoms incorporation during the early stages of crystallization, resulting in partially bonded framework Al due to lower polarization ability on Na⁺. In contrast, using Al(OH)₃ as the Al source (denoted as Z5-H) accelerates the nucleation process and leads to the formation of smaller particle size. Notably, the ²⁷Al multiple quantum magic angle spinning nuclear magnetic resonance (MQMAS NMR) results revealed that pure OH⁻ ions facilitate the preferential localization of Al atoms at T11 sites within the ZSM-5 framework, where the acid strength is reduced due to the larger Si-O-Al bond angle. The unique Al distributions are attributed to the strong polarization ability induced by the electrostatic attraction of OH⁻ ions to Na⁺. This study enhances our understanding of how different anionic environments influence Al placement, enabling more targeted design and synthesis of zeolite materials with tailored catalytic properties.

{"title":"Impact of anionic species on the crystallization and aluminum localization in the zeolite framework","authors":"Liang Zhao , Yong Wang , Peipei Xiao , Hiroto Toyoda , Qi Li , Yuqin Sun , Bekhti Samya , Hermann Gies , Toshiyuki Yokoi","doi":"10.1016/j.micromeso.2024.113456","DOIUrl":"10.1016/j.micromeso.2024.113456","url":null,"abstract":"<div><div>The distribution of acid sites, which are derived from tetrahedrally coordinated aluminum (Al) atoms within zeolite framework plays a critical role in the acidic catalyzed reactions, is strongly influenced by electrostatic interactions between cationic structure-directing agents (SDAs) and anionic charges. Herein, we synthesized various ZSM-5 zeolites without OSDAs and conducted an in-situ analysis to investigate the impact of anionic species from various Al sources on the crystallization and acid site localization in the framework. The results demonstrated that when Al(NO<sub>3</sub>)<sub>3</sub> is used as the Al source (denoted as Z5-N), the electronic environment influenced by NO<sub>3</sub>⁻ alters the framework formation pathway, leading to the creation of distorted, tetracoordinated Al intermediates. This process enhances Al atoms incorporation during the early stages of crystallization, resulting in partially bonded framework Al due to lower polarization ability on Na<sup>+</sup>. In contrast, using Al(OH)₃ as the Al source (denoted as Z5-H) accelerates the nucleation process and leads to the formation of smaller particle size. Notably, the <sup>2</sup>⁷Al multiple quantum magic angle spinning nuclear magnetic resonance (MQMAS NMR) results revealed that pure OH⁻ ions facilitate the preferential localization of Al atoms at T11 sites within the ZSM-5 framework, where the acid strength is reduced due to the larger Si-O-Al bond angle. The unique Al distributions are attributed to the strong polarization ability induced by the electrostatic attraction of OH⁻ ions to Na⁺. This study enhances our understanding of how different anionic environments influence Al placement, enabling more targeted design and synthesis of zeolite materials with tailored catalytic properties.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113456"},"PeriodicalIF":4.8,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis of Two-Dimensional Zeolite-Templated Carbons with Ordered Micropores

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-14 DOI: 10.1016/j.micromeso.2024.113459

Chaehoon Kim , Seunghyuck Chi , Hyeonsuk Yoo , Yongjin Lee , Minkee Choi

Zeolite-templated carbons (ZTCs) are a unique class of carbon materials characterized by ordered microporous structures, large surface areas, and substantial micropore volumes. ZTCs are synthesized by replicating the microporous structures of zeolite templates with carbon. Typically, zeolites with three-dimensional (3D) micropore connectivity have been used as templates for carbon deposition, producing ZTCs with 3D microporous channels and framework structures. In this study, we extend the synthesis of ZTCs using zeolite templates with two-dimensional (2D) micropore connectivity, which enables the production of 2D ZTCs—carbon nanosheets with vertically aligned ordered micropores. By studying 2D zeolites with various structures (UTL, IWV, MWW, and FER) and chemical compositions as templates, we identified key factors that govern the faithful replication of zeolite micropores with a carbon framework. Zeolite structures with large micropore apertures (≥12-membered rings), such as UTL and IWV, and a high density of acid sites (B or Al) were found to be beneficial for accurate carbon replication. The use of NaOH aqueous solution for template etching proved more effective in producing high-quality 2D ZTCs without inorganic residue, compared to the conventionally used HCl/HF aqueous solutions. Negative surface charges generated at carbon surfaces in highly alkaline NaOH solutions inhibited rapid stacking of carbon nanosheets via π-π interaction, which can cause the trapping of inorganic residues. We believe that the resulting 2D ZTCs hold significant promise for the fabrication of advanced membranes and energy storage devices.

{"title":"Synthesis of Two-Dimensional Zeolite-Templated Carbons with Ordered Micropores","authors":"Chaehoon Kim , Seunghyuck Chi , Hyeonsuk Yoo , Yongjin Lee , Minkee Choi","doi":"10.1016/j.micromeso.2024.113459","DOIUrl":"10.1016/j.micromeso.2024.113459","url":null,"abstract":"<div><div>Zeolite-templated carbons (ZTCs) are a unique class of carbon materials characterized by ordered microporous structures, large surface areas, and substantial micropore volumes. ZTCs are synthesized by replicating the microporous structures of zeolite templates with carbon. Typically, zeolites with three-dimensional (3D) micropore connectivity have been used as templates for carbon deposition, producing ZTCs with 3D microporous channels and framework structures. In this study, we extend the synthesis of ZTCs using zeolite templates with two-dimensional (2D) micropore connectivity, which enables the production of 2D ZTCs—carbon nanosheets with vertically aligned ordered micropores. By studying 2D zeolites with various structures (UTL, IWV, MWW, and FER) and chemical compositions as templates, we identified key factors that govern the faithful replication of zeolite micropores with a carbon framework. Zeolite structures with large micropore apertures (≥12-membered rings), such as UTL and IWV, and a high density of acid sites (B or Al) were found to be beneficial for accurate carbon replication. The use of NaOH aqueous solution for template etching proved more effective in producing high-quality 2D ZTCs without inorganic residue, compared to the conventionally used HCl/HF aqueous solutions. Negative surface charges generated at carbon surfaces in highly alkaline NaOH solutions inhibited rapid stacking of carbon nanosheets via π-π interaction, which can cause the trapping of inorganic residues. We believe that the resulting 2D ZTCs hold significant promise for the fabrication of advanced membranes and energy storage devices.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113459"},"PeriodicalIF":4.8,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The notable features of mesoporous aluminosilicates as catalytic supports for hydrodearomatization and hydrodesulfurization of fuels

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-13 DOI: 10.1016/j.micromeso.2024.113457

A. Abdrassilova , G. Vassilina , K. Abdildina , L. Briones , A. Peral , J.M. Escola

Despite being discovered more than 25 years ago, mesoporous aluminosilicates are still very relevant materials, considering the huge number of publications appearing every year harnessing them. Their notable features such as high BET surface area, accessible mesopore size, mild acidity and tunable pore wall thickness have resulted in different successful catalytic applications. Additionally, different kinds of mesoporous aluminosilicates may be found in literature (MCM-41, MCM-48, HMS, SBA-15, SBA-16, etc.) that allow to tailor to certain extent some physicochemical properties such as the spatial group, mesopore size and dimension, the pore wall thickness and consequently the hydrothermal stability, for the wanted catalytic application. This review is focused on discussing the main characteristics of the most common mesoporous aluminosilicates and exploring their reported performance in literature as supports of bifunctional catalysts for the hydrodearomatization (HDA) and desulfurization (HDS) of fuels. Although their hydrothermal stability has always been questioned by their lack of crystallinity, several successful applications of both MCM-41 and SBA-15 as supports of bifunctional catalysts for HDA/HDS of model compounds such as dibenzothiophene (DBT) can be found in literature, which in some cases interestingly also point out the prolonged stability of the catalyst, leading towards high yields of fuels by its mild acidity. Additionally, supported metal catalysts over mesoporous aluminosilicates might be the basis for the preparation of advanced bulk metal hydroprocessing catalysts, by application of different etching strategies. Therefore, this review will show these promising catalytic outcomes that opens up the application of mesoporous aluminosilicates as supports of bifunctional catalysts devoted to HDA/HDS of not only model sulfur/aromatic compounds but true fuels as well such as those proceeding from Kazakhstan oil.

{"title":"The notable features of mesoporous aluminosilicates as catalytic supports for hydrodearomatization and hydrodesulfurization of fuels","authors":"A. Abdrassilova , G. Vassilina , K. Abdildina , L. Briones , A. Peral , J.M. Escola","doi":"10.1016/j.micromeso.2024.113457","DOIUrl":"10.1016/j.micromeso.2024.113457","url":null,"abstract":"<div><div>Despite being discovered more than 25 years ago, mesoporous aluminosilicates are still very relevant materials, considering the huge number of publications appearing every year harnessing them. Their notable features such as high BET surface area, accessible mesopore size, mild acidity and tunable pore wall thickness have resulted in different successful catalytic applications. Additionally, different kinds of mesoporous aluminosilicates may be found in literature (MCM-41, MCM-48, HMS, SBA-15, SBA-16, etc.) that allow to tailor to certain extent some physicochemical properties such as the spatial group, mesopore size and dimension, the pore wall thickness and consequently the hydrothermal stability, for the wanted catalytic application. This review is focused on discussing the main characteristics of the most common mesoporous aluminosilicates and exploring their reported performance in literature as supports of bifunctional catalysts for the hydrodearomatization (HDA) and desulfurization (HDS) of fuels. Although their hydrothermal stability has always been questioned by their lack of crystallinity, several successful applications of both MCM-41 and SBA-15 as supports of bifunctional catalysts for HDA/HDS of model compounds such as dibenzothiophene (DBT) can be found in literature, which in some cases interestingly also point out the prolonged stability of the catalyst, leading towards high yields of fuels by its mild acidity. Additionally, supported metal catalysts over mesoporous aluminosilicates might be the basis for the preparation of advanced bulk metal hydroprocessing catalysts, by application of different etching strategies. Therefore, this review will show these promising catalytic outcomes that opens up the application of mesoporous aluminosilicates as supports of bifunctional catalysts devoted to HDA/HDS of not only model sulfur/aromatic compounds but true fuels as well such as those proceeding from Kazakhstan oil.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113457"},"PeriodicalIF":4.8,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Naproxen-loaded mesoporous silica nanoparticles: How can the process of incorporation affect drug placement, drug release and the in vitro naproxen irritant potential?

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-12-13 DOI: 10.1016/j.micromeso.2024.113458

Nadine Lysyk Funk , Flávia Carvalho Tavaniello , Juliana Dos Santos , Edilson Valmir Benvenutti , Silvio Buchner , Karina Paese , Monique Deon , Ruy Carlos Ruver Beck

Mesoporous silica nanoparticles (MSN) serve as versatile drug nanocarriers to avoid the interaction of highly irritant drugs with stomach mucosa, such as nonsteroidal anti-inflammatory drugs (NSAIDs). In this study, spherical and nanometric particles (181 ± 11 nm) with long-channel nanopores (∼2.5 nm in diameter) hexagonally arranged were synthesised. The NSAID naproxen (NPX) was incorporated into MSN by using the incipient wetness method. NPX ethanolic solutions of 30 mg mL⁻¹ (NPX-ES-30) and 40 mg mL⁻¹ (NPX-ES-40) were employed to obtain MSN-NPX30-1 and MSN-NPX40-1, corresponding to 8.26 % and 10.12 % (w/w) NPX loading, respectively. A second incorporation was performed to produced MSN-NPX30-2 and MSN-NPX40-2, with 13.45 % and 16.78 % (w/w) NPX loading, respectively. A reduction in surface area and pore volume was observed for all drug-loaded formulations compared to bare MSN. Notably, formulations prepared with NPX-ES-40 exhibited a less pronounced reduction, indicating that a portion of the drug was likely positioned outside the MSN pores. In contrast, NPX-ES-30 formulations showed efficient internalization of NPX into the mesopores, resulting in a more significant reduction in surface area and pore volume following drug incorporation. The enhanced silica–drug interaction in these formulations resulted in a slower NPX release rate compared with the NPX-ES-40 formulations, and a lower in vitro irritation score for the hen's eggs test on chorioallantoic membrane. In conclusion, the concentration of the NPX solution influenced the drug placement within MSN pores and, therefore, the NPX drug release rate and in vitro irritant potential.

{"title":"Naproxen-loaded mesoporous silica nanoparticles: How can the process of incorporation affect drug placement, drug release and the in vitro naproxen irritant potential?","authors":"Nadine Lysyk Funk , Flávia Carvalho Tavaniello , Juliana Dos Santos , Edilson Valmir Benvenutti , Silvio Buchner , Karina Paese , Monique Deon , Ruy Carlos Ruver Beck","doi":"10.1016/j.micromeso.2024.113458","DOIUrl":"10.1016/j.micromeso.2024.113458","url":null,"abstract":"<div><div>Mesoporous silica nanoparticles (MSN) serve as versatile drug nanocarriers to avoid the interaction of highly irritant drugs with stomach mucosa, such as nonsteroidal anti-inflammatory drugs (NSAIDs). In this study, spherical and nanometric particles (181 ± 11 nm) with long-channel nanopores (∼2.5 nm in diameter) hexagonally arranged were synthesised. The NSAID naproxen (NPX) was incorporated into MSN by using the incipient wetness method. NPX ethanolic solutions of 30 mg mL<sup>−1</sup> (NPX-ES-30) and 40 mg mL<sup>−1</sup> (NPX-ES-40) were employed to obtain MSN-NPX30-1 and MSN-NPX40-1, corresponding to 8.26 % and 10.12 % (w/w) NPX loading, respectively. A second incorporation was performed to produced MSN-NPX30-2 and MSN-NPX40-2, with 13.45 % and 16.78 % (w/w) NPX loading, respectively. A reduction in surface area and pore volume was observed for all drug-loaded formulations compared to bare MSN. Notably, formulations prepared with NPX-ES-40 exhibited a less pronounced reduction, indicating that a portion of the drug was likely positioned outside the MSN pores. In contrast, NPX-ES-30 formulations showed efficient internalization of NPX into the mesopores, resulting in a more significant reduction in surface area and pore volume following drug incorporation. The enhanced silica–drug interaction in these formulations resulted in a slower NPX release rate compared with the NPX-ES-40 formulations, and a lower <em>in vitro</em> irritation score for the hen's eggs test on chorioallantoic membrane. In conclusion, the concentration of the NPX solution influenced the drug placement within MSN pores and, therefore, the NPX drug release rate and <em>in vitro</em> irritant potential.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"384 ","pages":"Article 113458"},"PeriodicalIF":4.8,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0