Nanoporous carbon (NPC) is widely utilized due to its highly developed pore structure. The complex structure-property relationships of NPC necessitate simulation methods to complement experimental approaches, with structural model construction serving as the foundation. Regulating pore structures during construction of NPC models poses a significant challenge, and existing strategies for introducing pores have inherent limitations. In this work, NPC models were constructed using the random packing method, incorporating virtual atoms (VAs) to regulate pore development, achieving targeted control over the pore structure. The results indicate that the system density is a critical factor in determining the porosity range of NPC models, whereas VAs provide an effective means to regulate pore characteristics. By adjusting the number and radius of VAs, the pore characteristics of the models can be tuned, although their effects on different features vary. The number of VAs significantly influences SSA, which increases with the number of VAs, whereas VA radius predominantly affects porosity, increasing as the radius expands. Furthermore, the NPC-SDG-AC model was developed with an SSA of 968 m2/g and a pore size distribution consistent with actual microporous distribution. NPC-1, NPC-2, and NPC-3 models were also constructed, exhibiting mesoporous, large microporous, and small microporous characteristics.
{"title":"Development of nanoporous carbon models with tunable pore structures via the random packing-virtual atom method","authors":"Yihuan Zhou, Qiang Xie, Dingcheng Liang, Hongyang Zhou, Jinchang Liu, Yutong Sha, Bingjie Wang, Shimei Gu","doi":"10.1016/j.micromeso.2024.113407","DOIUrl":"10.1016/j.micromeso.2024.113407","url":null,"abstract":"<div><div>Nanoporous carbon (NPC) is widely utilized due to its highly developed pore structure. The complex structure-property relationships of NPC necessitate simulation methods to complement experimental approaches, with structural model construction serving as the foundation. Regulating pore structures during construction of NPC models poses a significant challenge, and existing strategies for introducing pores have inherent limitations. In this work, NPC models were constructed using the random packing method, incorporating virtual atoms (VAs) to regulate pore development, achieving targeted control over the pore structure. The results indicate that the system density is a critical factor in determining the porosity range of NPC models, whereas VAs provide an effective means to regulate pore characteristics. By adjusting the number and radius of VAs, the pore characteristics of the models can be tuned, although their effects on different features vary. The number of VAs significantly influences SSA, which increases with the number of VAs, whereas VA radius predominantly affects porosity, increasing as the radius expands. Furthermore, the NPC-SDG-AC model was developed with an SSA of 968 m<sup>2</sup>/g and a pore size distribution consistent with actual microporous distribution. NPC-1, NPC-2, and NPC-3 models were also constructed, exhibiting mesoporous, large microporous, and small microporous characteristics.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113407"},"PeriodicalIF":4.8,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656290","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}
Pub Date : 2024-11-07DOI: 10.1016/j.micromeso.2024.113404
Wuyue Yu , Hangzhen Lan , Zhen Wu , Daodong Pan , Yichun Wu
This study investigates the adsorption behavior of biogenic amines (BAs) using mesoporous silica materials, specifically SBA-15 and SBA-16, as well as their carboxyl-functionalized derivatives (SBA-15-C and SBA-16-C). The materials were synthesized and characterized using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, and nitrogen adsorption-desorption analyses, confirming successful functionalization and the preservation of mesoporous structures. Adsorption kinetics and isotherms were evaluated to assess the efficiency and capacity of these materials in adsorbing phenylethylamine and tryptamine. The results demonstrated that carboxylation, despite reducing pore size and surface area, significantly enhanced the adsorption capacity. SBA-15-C exhibited the highest adsorption capacity, with a maximum of 129.9 mg g−1, surpassing other recently reported adsorbents. The primary adsorption mechanisms were identified as hydrogen bonding and N-H bond interactions between the -NH2 groups of BAs and the -OH or -COOH groups on the SBA surfaces. Additional mechanisms, including ion-dipole interactions and size exclusion effects, also contributed to the adsorption process. The improved performance of carboxylated SBA materials is attributed to their increased negative surface charge, which enhances their affinity for positively charged BAs. Additionally, density functional theory calculations and molecular docking simulations were employed to further investigate the interaction mechanisms between the adsorbents and BAs, confirming the significance of electrostatic interactions and hydrogen bonding at specific binding sites. These findings suggest that carboxylated SBA-15 is highly effective for the selective extraction of BAs from complex matrices, offering potential for practical applications in food safety.
{"title":"Enhanced selective extraction of biogenic amines using carboxyl-functionalized SBA-15 and SBA-16 mesoporous silica","authors":"Wuyue Yu , Hangzhen Lan , Zhen Wu , Daodong Pan , Yichun Wu","doi":"10.1016/j.micromeso.2024.113404","DOIUrl":"10.1016/j.micromeso.2024.113404","url":null,"abstract":"<div><div>This study investigates the adsorption behavior of biogenic amines (BAs) using mesoporous silica materials, specifically SBA-15 and SBA-16, as well as their carboxyl-functionalized derivatives (SBA-15-C and SBA-16-C). The materials were synthesized and characterized using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, and nitrogen adsorption-desorption analyses, confirming successful functionalization and the preservation of mesoporous structures. Adsorption kinetics and isotherms were evaluated to assess the efficiency and capacity of these materials in adsorbing phenylethylamine and tryptamine. The results demonstrated that carboxylation, despite reducing pore size and surface area, significantly enhanced the adsorption capacity. SBA-15-C exhibited the highest adsorption capacity, with a maximum of 129.9 mg g<sup>−1</sup>, surpassing other recently reported adsorbents. The primary adsorption mechanisms were identified as hydrogen bonding and N-H bond interactions between the -NH<sub>2</sub> groups of BAs and the -OH or -COOH groups on the SBA surfaces. Additional mechanisms, including ion-dipole interactions and size exclusion effects, also contributed to the adsorption process. The improved performance of carboxylated SBA materials is attributed to their increased negative surface charge, which enhances their affinity for positively charged BAs. Additionally, density functional theory calculations and molecular docking simulations were employed to further investigate the interaction mechanisms between the adsorbents and BAs, confirming the significance of electrostatic interactions and hydrogen bonding at specific binding sites. These findings suggest that carboxylated SBA-15 is highly effective for the selective extraction of BAs from complex matrices, offering potential for practical applications in food safety.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113404"},"PeriodicalIF":4.8,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656302","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}
Pub Date : 2024-11-06DOI: 10.1016/j.micromeso.2024.113402
Chunlai Liu, Wei Wang, Na Wang, Zelong Liu, Peihang Shen, Jianglei Hu, Fengwei Shi
Wastewater containing heavy metal ions, such as Cu2+, that are released into the environment will cause irreparable damage to the nature and human health of living. It is, therefore, absolutely crucial to remove these toxic ions from water. Herein, this paper utilizes the cyano group as a functional reagent to prepare carboxyl-functionalized SBA16 for adsorbing Cu2+ in water. In this paper, 2-cyanoethyltriethoxysilane is employed as a functionalizing reagent to prepare carboxyl-functionalized SBA16 through a one-pot method. The prepared material was characterized using various techniques, such as WXRD, TEM, FT-IR, and XPS. The results indicated that the introduction of the functionalizing reagent did not disrupt the original cage-like cubic mesoporous structure (Im3m symmetry) of SBA16. Crucial adsorption factors, namely pH, adsorbent dosage, Cu2+ initial concentration, and contact time, affecting the removal of Cu2+ were monitored and the optimum adsorption conditions were determined. Isotherm and kinetic investigations were conducted and a non-linear fitting method of experimental data was used to obtain isotherm and kinetic parameters. Maximum adsorption capacity reaches 181.3 mg g−1 was achieved in 60 min at pH = 3. Adsorption kinetics and adsorption isotherm followed the pseudo-second-order (R2 = 0.999) and Langmuir (R2 = 0.999) models, respectively. This suggests that the adsorption process primarily involves chemisorption and monolayer coverage. Thermodynamic parameters showed the spontaneous and endothermic nature of the adsorption process. After 5 cycles, the adsorbent still maintains a good adsorption capacity for Cu2+. This suggests promising applications for the adsorbent in treating wastewater containing Cu2+.
{"title":"Synthesis of cubic mesoporous silica SBA16 functionalized with carboxylic acid in a one-pot process for efficient removal of wastewater containing Cu2+: Adsorption isotherms, kinetics, and thermodynamics","authors":"Chunlai Liu, Wei Wang, Na Wang, Zelong Liu, Peihang Shen, Jianglei Hu, Fengwei Shi","doi":"10.1016/j.micromeso.2024.113402","DOIUrl":"10.1016/j.micromeso.2024.113402","url":null,"abstract":"<div><div>Wastewater containing heavy metal ions, such as Cu<sup>2+</sup>, that are released into the environment will cause irreparable damage to the nature and human health of living. It is, therefore, absolutely crucial to remove these toxic ions from water. Herein, this paper utilizes the cyano group as a functional reagent to prepare carboxyl-functionalized SBA16 for adsorbing Cu<sup>2+</sup> in water. In this paper, 2-cyanoethyltriethoxysilane is employed as a functionalizing reagent to prepare carboxyl-functionalized SBA16 through a one-pot method. The prepared material was characterized using various techniques, such as WXRD, TEM, FT-IR, and XPS. The results indicated that the introduction of the functionalizing reagent did not disrupt the original cage-like cubic mesoporous structure (Im3m symmetry) of SBA16. Crucial adsorption factors, namely pH, adsorbent dosage, Cu<sup>2+</sup> initial concentration, and contact time, affecting the removal of Cu<sup>2+</sup> were monitored and the optimum adsorption conditions were determined. Isotherm and kinetic investigations were conducted and a non-linear fitting method of experimental data was used to obtain isotherm and kinetic parameters. Maximum adsorption capacity reaches 181.3 mg g<sup>−1</sup> was achieved in 60 min at pH = 3. Adsorption kinetics and adsorption isotherm followed the pseudo-second-order (R<sup>2</sup> = 0.999) and Langmuir (R<sup>2</sup> = 0.999) models, respectively. This suggests that the adsorption process primarily involves chemisorption and monolayer coverage. Thermodynamic parameters showed the spontaneous and endothermic nature of the adsorption process. After 5 cycles, the adsorbent still maintains a good adsorption capacity for Cu<sup>2+</sup>. This suggests promising applications for the adsorbent in treating wastewater containing Cu<sup>2+</sup>.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113402"},"PeriodicalIF":4.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656292","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}
Pub Date : 2024-11-06DOI: 10.1016/j.micromeso.2024.113401
Shixuan Wang , Fang Yuan , Jialin Liang , Lin Peng , Chunquan Li , Qing Sun , Zhiming Sun
Photo-assisted catalytic oxidation is a promising and sustainable method for the formaldehyde (HCHO) degradation. Catalyst loading and surface adsorbed oxygen species are common strategies to enhance the efficiency of photo-assisted catalytic oxidation. In this work, acid-treated zeolite-based natural zeolites (mordenite and stellerite) were used as supports, to obtain Co3O4-natural zeolite composites by impregnation and MOF-templated methods. Under the combined action of visible light irradiation and heat condition, the photo-assisted thermal catalytic performance of different composites was determined. Among these composites, the Co-AS (Co3O4-acid-treated stellerite) composite exhibited the best HCHO mineralization performance. The use of acid-treated stellerite as a catalyst carrier effectively reduced the crystallite size of Co3O4, improved its dispersibility, and increased the surface adsorbed oxygen species, contributing to enhanced catalytic efficiency. The in-situ DRIFTs results showed that the main intermediates of photo-assisted thermal catalysis degradation were dioxymethylene (DOM) and HCOO−. Additionally, the reusability performance of the composites was also investigated. Experimental results showed that the composite had good photo-assisted thermal catalytic performance and durability, making it a promising catalyst for indoor air purification.
{"title":"Enhanced photo-assisted thermal catalytic oxidation of formaldehyde via abundant surface adsorbed oxygen in Co3O4 with the assistance of natural zeolite","authors":"Shixuan Wang , Fang Yuan , Jialin Liang , Lin Peng , Chunquan Li , Qing Sun , Zhiming Sun","doi":"10.1016/j.micromeso.2024.113401","DOIUrl":"10.1016/j.micromeso.2024.113401","url":null,"abstract":"<div><div>Photo-assisted catalytic oxidation is a promising and sustainable method for the formaldehyde (HCHO) degradation. Catalyst loading and surface adsorbed oxygen species are common strategies to enhance the efficiency of photo-assisted catalytic oxidation. In this work, acid-treated zeolite-based natural zeolites (mordenite and stellerite) were used as supports, to obtain Co<sub>3</sub>O<sub>4</sub>-natural zeolite composites by impregnation and MOF-templated methods. Under the combined action of visible light irradiation and heat condition, the photo-assisted thermal catalytic performance of different composites was determined. Among these composites, the Co-AS (Co<sub>3</sub>O<sub>4</sub>-acid-treated stellerite) composite exhibited the best HCHO mineralization performance. The use of acid-treated stellerite as a catalyst carrier effectively reduced the crystallite size of Co<sub>3</sub>O<sub>4</sub>, improved its dispersibility, and increased the surface adsorbed oxygen species, contributing to enhanced catalytic efficiency. The in-situ DRIFTs results showed that the main intermediates of photo-assisted thermal catalysis degradation were dioxymethylene (DOM) and HCOO<sup>−</sup>. Additionally, the reusability performance of the composites was also investigated. Experimental results showed that the composite had good photo-assisted thermal catalytic performance and durability, making it a promising catalyst for indoor air purification.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113401"},"PeriodicalIF":4.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656301","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}
Pub Date : 2024-11-06DOI: 10.1016/j.micromeso.2024.113400
Susan C. Citrak , Beatriz Ehlke , Stacey I. Zones , Dan Xie , Son-Jong Hwang , Andrew S. Ichimura , Linjuan Zhang , Shibo Xi , Scott R.J. Oliver
The ionic liquids diisopropylimidazolium bromide (DIPI) and diisobutylimidazolium bromide (DIBU) were used both as solvents and structure-directing agents (SDAs) to obtain AlPO4-5 and MnAPO-5 (Mn-AFI) molecular sieves. For increasing level of manganese, DIBU always yielded pure-phase Mn-AFI whereas DIPI led to amorphous product when more than 0.13 eq of Mn was added. Varying amounts of water, HF and metal led to AFI, cristobalite or tridymite phases. We also explored the use of nickel as the metal dopant, and although AFI phase were obtained under certain conditions, no framework incorporation of the metal was observed. Because of the vanishingly low vapor pressure of the ILs, the synthesis does not carry the risk of pressure build-up. The ILs were easily and fully recyclable and used for multiple syntheses. The MnAPO-5 material was characterized with powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), electron paramagnetic resonance (EPR), multinuclear solid-state nuclear magnetic resonance (SS-NMR) and X-ray absorption fine structure (XAFS). These findings provide new insight into the ionothermal synthesis of metal-doped AFI frameworks with possible implications in catalytic applications.
{"title":"MAPO-5 molecular sieves from alkylimidazolium bromide ionic liquids","authors":"Susan C. Citrak , Beatriz Ehlke , Stacey I. Zones , Dan Xie , Son-Jong Hwang , Andrew S. Ichimura , Linjuan Zhang , Shibo Xi , Scott R.J. Oliver","doi":"10.1016/j.micromeso.2024.113400","DOIUrl":"10.1016/j.micromeso.2024.113400","url":null,"abstract":"<div><div>The ionic liquids diisopropylimidazolium bromide (DIPI) and diisobutylimidazolium bromide (DIBU) were used both as solvents and structure-directing agents (SDAs) to obtain AlPO<sub>4</sub>-5 and MnAPO-5 (Mn-AFI) molecular sieves. For increasing level of manganese, DIBU always yielded pure-phase Mn-AFI whereas DIPI led to amorphous product when more than 0.13 eq of Mn was added. Varying amounts of water, HF and metal led to AFI, cristobalite or tridymite phases. We also explored the use of nickel as the metal dopant, and although AFI phase were obtained under certain conditions, no framework incorporation of the metal was observed. Because of the vanishingly low vapor pressure of the ILs, the synthesis does not carry the risk of pressure build-up. The ILs were easily and fully recyclable and used for multiple syntheses. The MnAPO-5 material was characterized with powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), electron paramagnetic resonance (EPR), multinuclear solid-state nuclear magnetic resonance (SS-NMR) and X-ray absorption fine structure (XAFS). These findings provide new insight into the ionothermal synthesis of metal-doped AFI frameworks with possible implications in catalytic applications.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113400"},"PeriodicalIF":4.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656300","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}
Pub Date : 2024-11-06DOI: 10.1016/j.micromeso.2024.113403
Winters Kexi Guo, Derek R. Zhu, Grant Zeszutek, Emma Rosko, Michael J. Janik, Gina Noh
Continuous ion exchange is a more sustainable alternative to current methods for removing common impurities from lithium sources. In this work, we examine ion-adsorbent interactions for Mg2+ and Ca2+ with microporous titanosilicate ETS-10, an ion exchange solid with promising performance, using experimental and computational (density functional theory, DFT) methods. Ion exchange affinity for Mg2+ and Ca2+ using the Na+-form of ETS-10 are quantified from measured equilibrium isotherms, analyzed using a modified Langmuir isotherm accounting for overall stoichiometric desorption/adsorption in the cation exchange process. The equilibrium constant for ion exchange using Na-ETS-10 is greatest for Ca and decreases in order of Mg, K, and Li, respectively. These differences in ion exchange affinity are consistent with trends in DFT-derived ion exchange energies, which account for hydration and solvation of cations using a thermochemical cycle. These equilibrium constant values and ion exchange energies suggest that exchange of Ca2+, Mg2+, and K+ using Na-ETS-10 is more favorable than that of Li+. Indeed, competitive ion exchange of equimolar aqueous mixtures of Li+ and each of K+, Mg2+, or Ca2+ demonstrate selective uptake of the non-lithium cation into the solid, thereby concentrating Li+ in the aqueous solution while removing impurity cations.
{"title":"Alkali and alkaline earth ion exchange affinity in ETS-10 toward aqueous lithium separation","authors":"Winters Kexi Guo, Derek R. Zhu, Grant Zeszutek, Emma Rosko, Michael J. Janik, Gina Noh","doi":"10.1016/j.micromeso.2024.113403","DOIUrl":"10.1016/j.micromeso.2024.113403","url":null,"abstract":"<div><div>Continuous ion exchange is a more sustainable alternative to current methods for removing common impurities from lithium sources. In this work, we examine ion-adsorbent interactions for Mg<sup>2+</sup> and Ca<sup>2+</sup> with microporous titanosilicate ETS-10, an ion exchange solid with promising performance, using experimental and computational (density functional theory, DFT) methods. Ion exchange affinity for Mg<sup>2+</sup> and Ca<sup>2+</sup> using the Na<sup>+</sup>-form of ETS-10 are quantified from measured equilibrium isotherms, analyzed using a modified Langmuir isotherm accounting for overall stoichiometric desorption/adsorption in the cation exchange process. The equilibrium constant for ion exchange using Na-ETS-10 is greatest for Ca and decreases in order of Mg, K, and Li, respectively. These differences in ion exchange affinity are consistent with trends in DFT-derived ion exchange energies, which account for hydration and solvation of cations using a thermochemical cycle. These equilibrium constant values and ion exchange energies suggest that exchange of Ca<sup>2+</sup>, Mg<sup>2+</sup>, and K<sup>+</sup> using Na-ETS-10 is more favorable than that of Li<sup>+</sup>. Indeed, competitive ion exchange of equimolar aqueous mixtures of Li<sup>+</sup> and each of K<sup>+</sup>, Mg<sup>2+</sup>, or Ca<sup>2+</sup> demonstrate selective uptake of the non-lithium cation into the solid, thereby concentrating Li<sup>+</sup> in the aqueous solution while removing impurity cations.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"383 ","pages":"Article 113403"},"PeriodicalIF":4.8,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658540","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}
Pub Date : 2024-11-02DOI: 10.1016/j.micromeso.2024.113399
Ying Gao , Jiafeng Zhang , Yanan Tu , Weidong Wang , Ziqi Zhu , Zhiqiang Xu
The preparation of hierarchical porous silica aerogels from coal gasification fine slag (CGFS) offers an effective approach to achieving high-value utilization of solid waste and reducing the production cost of solid adsorbent matrix materials. However, the main challenges involve overcoming technical barriers to efficiently and value-added conversion of CGFS into silica aerogels with CO₂ adsorption properties, as well as elucidating the phase transformation mechanisms during the synthesis process. In this study, CGFS was used as the raw material to obtain a silicon-containing precursor through pre-decarbonization (with ash content as high as 99.82 %) and alkali dissolution treatment. A hierarchical porous silica aerogel was then synthesized using an efficient hydrothermal process. The effect of alkali dissolution on silicon extraction and the phase transformation mechanisms were thoroughly discussed, and the leaching mechanism was analyzed through thermodynamic and kinetic models. The results showed that the high leaching rate of silicon was attributed to the presence of a large amount of amorphous SiO₂ in the decarbonized fine slag (DCFS), while the formation of zeolite Na-P1 and hydroxysodalite during the alkali dissolution process affected the efficiency of silicon extraction. Then, the structural formation mechanism and CO₂ adsorption properties of the hierarchical porous silica aerogels were analyzed using N₂ adsorption-desorption and CO₂-TPD. The SiO₂-1-30-0.5 exhibited a high CO₂ adsorption ability of 1.53 mmol g−1, and the CO₂ adsorption capacity maintained 94.78 % of the original value and after 5 adsorption-desorption cycles.
{"title":"Synthesis of hierarchical porous silica aerogel for CO2 adsorption using decarbonized coal gasification fine slag","authors":"Ying Gao , Jiafeng Zhang , Yanan Tu , Weidong Wang , Ziqi Zhu , Zhiqiang Xu","doi":"10.1016/j.micromeso.2024.113399","DOIUrl":"10.1016/j.micromeso.2024.113399","url":null,"abstract":"<div><div>The preparation of hierarchical porous silica aerogels from coal gasification fine slag (CGFS) offers an effective approach to achieving high-value utilization of solid waste and reducing the production cost of solid adsorbent matrix materials. However, the main challenges involve overcoming technical barriers to efficiently and value-added conversion of CGFS into silica aerogels with CO₂ adsorption properties, as well as elucidating the phase transformation mechanisms during the synthesis process. In this study, CGFS was used as the raw material to obtain a silicon-containing precursor through pre-decarbonization (with ash content as high as 99.82 %) and alkali dissolution treatment. A hierarchical porous silica aerogel was then synthesized using an efficient hydrothermal process. The effect of alkali dissolution on silicon extraction and the phase transformation mechanisms were thoroughly discussed, and the leaching mechanism was analyzed through thermodynamic and kinetic models. The results showed that the high leaching rate of silicon was attributed to the presence of a large amount of amorphous SiO₂ in the decarbonized fine slag (DCFS), while the formation of zeolite Na-P1 and hydroxysodalite during the alkali dissolution process affected the efficiency of silicon extraction. Then, the structural formation mechanism and CO₂ adsorption properties of the hierarchical porous silica aerogels were analyzed using N₂ adsorption-desorption and CO₂-TPD. The SiO₂-1-30-0.5 exhibited a high CO₂ adsorption ability of 1.53 mmol g<sup>−1</sup>, and the CO₂ adsorption capacity maintained 94.78 % of the original value and after 5 adsorption-desorption cycles.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113399"},"PeriodicalIF":4.8,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586329","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}
Pub Date : 2024-10-30DOI: 10.1016/j.micromeso.2024.113396
Xue Li, Xiaolei Li, Xiaoming Liu, Xinning Song, Bo Wang, Lulu Xu, Shuo Tao
Exploring novel strategies for the preparation of zeolitic materials with high performance continues to be of great significance. Here we report a general solid-state approach for fabricating aluminophosphate (AlPO)-based zeotypes by directly calcining conventional amorphous precursors at 300 °C for just 30 min. Accordingly, AEL, AFI, LTA and CHA types of AlPO-based zeotypes with high crystallinity and similar textural properties to those of counterparts made by established synthesis approaches have been synthesized. As a demonstration, the catalytic performance of Mg-substituted AlPO-11 (S-MgAlPO-11) in hydroisomerization of n-hexadecane (n-C16) was also investigated. Compared with the Pt supported on conventional MgAlPO-11 (Pt/C-MgAlPO-11) catalyst, the Pt/S-MgAlPO-11catalyst exhibits higher isomerized (87 % vs. 84 %), multi-branched C16 (48 % vs. 30 %) yields and superior reaction stability, attributing to the improved diffusion property and appropriate metal-acid balance. This strategy provides an efficient approach to synthesis promising zeolitic catalysts for industrial applications.
{"title":"Solid-state synthesis of aluminophosphate-based zeotypes from conventional amorphous precursors: Strategy and catalytic performance","authors":"Xue Li, Xiaolei Li, Xiaoming Liu, Xinning Song, Bo Wang, Lulu Xu, Shuo Tao","doi":"10.1016/j.micromeso.2024.113396","DOIUrl":"10.1016/j.micromeso.2024.113396","url":null,"abstract":"<div><div>Exploring novel strategies for the preparation of zeolitic materials with high performance continues to be of great significance. Here we report a general solid-state approach for fabricating aluminophosphate (AlPO)-based zeotypes by directly calcining conventional amorphous precursors at 300 °C for just 30 min. Accordingly, <strong>AEL</strong>, <strong>AFI</strong>, <strong>LTA</strong> and <strong>CHA</strong> types of AlPO-based zeotypes with high crystallinity and similar textural properties to those of counterparts made by established synthesis approaches have been synthesized. As a demonstration, the catalytic performance of Mg-substituted AlPO-11 (S-MgAlPO-11) in hydroisomerization of <em>n</em>-hexadecane (<em>n</em>-C<sub>16</sub>) was also investigated. Compared with the Pt supported on conventional MgAlPO-11 (Pt/C-MgAlPO-11) catalyst, the Pt/S-MgAlPO-11catalyst exhibits higher isomerized (87 % vs. 84 %), multi-branched C<sub>16</sub> (48 % vs. 30 %) yields and superior reaction stability, attributing to the improved diffusion property and appropriate metal-acid balance. This strategy provides an efficient approach to synthesis promising zeolitic catalysts for industrial applications.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113396"},"PeriodicalIF":4.8,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586330","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}
Copper-exchanged zeolites have been subjected to several investigations because of their application as selective redox-active catalysts, and sensors. However, the ability of different types of zeolites to exchange Cu ions remains a matter of debate. All-atom molecular dynamics (MD) simulations, energy dispersive X-ray spectroscopy (EDS), and X-ray Fluorescence (XRF) methods have been used to evaluate the exchange of Cu(II) in mordenite and clinoptilolite zeolites using an aqueous method in the current study. Several parameters of copper ions have been measured for both types of zeolites, such as ion exchange ratio, mean square displacement (MSD), diffusion coefficient, and radial distribution function (RDF). These parameters were calculated for each zeolite system at different Cu ion concentrations in the feed solution. Copper exchange ratio and RDF analyses revealed a higher exchange ratio of copper ions in the mordenite framework. Analysis of the potential energy indicates the major adsorption sites for mordenite and clinoptilolite, which are located in the largest cavities of the zeolites. The adsorption energy of the mordenite sites (1.52 eV) was larger than that of clinoptilolite (1.28 eV). The stronger attraction between the copper ions and mordenite sites is consistent with the lower diffusion coefficients of the ions in this zeolite. The ion-exchange abilities of the zeolites were examined using EDS analysis. According to the EDS results, the mordenite zeolite exchanged more copper ions than the clinoptilolite, which is in agreement with the computational results.
由于铜交换沸石可用作选择性氧化还原催化剂和传感器，因此对其进行了多项研究。然而，不同类型的沸石交换铜离子的能力仍存在争议。本研究采用全原子分子动力学（MD）模拟、能量色散 X 射线光谱（EDS）和 X 射线荧光（XRF）方法，通过水溶液法评估了莫来石和沸石中 Cu（II）的交换。测量了两种沸石中铜离子的几个参数，如离子交换率、均方位移（MSD）、扩散系数和径向分布函数（RDF）。在进料溶液中铜离子浓度不同的情况下，对每种沸石系统的这些参数进行了计算。铜交换比和 RDF 分析表明，铜离子在莫来石框架中的交换比更高。势能分析表明，莫来石和鳞片沸石的主要吸附位点位于沸石的最大空腔中。莫来石位点的吸附能（1.52 eV）大于铮沸石（1.28 eV）。铜离子与莫来石位点之间更强的吸引力与该沸石中较低的离子扩散系数相一致。使用 EDS 分析法检测了沸石的离子交换能力。根据 EDS 分析结果，莫代沸石的铜离子交换率高于沸石，这与计算结果一致。
{"title":"Ion-exchange of copper into mordenite and clinoptilolite zeolites by molecular dynamics simulations and experimental investigations","authors":"Mehran Vaezi , Motahareh Noormohammadbeigi , Giuseppe Cruciani , Mojgan Zendehdel","doi":"10.1016/j.micromeso.2024.113397","DOIUrl":"10.1016/j.micromeso.2024.113397","url":null,"abstract":"<div><div>Copper-exchanged zeolites have been subjected to several investigations because of their application as selective redox-active catalysts, and sensors. However, the ability of different types of zeolites to exchange Cu ions remains a matter of debate. All-atom molecular dynamics (MD) simulations, energy dispersive X-ray spectroscopy (EDS), and X-ray Fluorescence (XRF) methods have been used to evaluate the exchange of Cu(II) in mordenite and clinoptilolite zeolites using an aqueous method in the current study. Several parameters of copper ions have been measured for both types of zeolites, such as ion exchange ratio, mean square displacement (MSD), diffusion coefficient, and radial distribution function (RDF). These parameters were calculated for each zeolite system at different Cu ion concentrations in the feed solution. Copper exchange ratio and RDF analyses revealed a higher exchange ratio of copper ions in the mordenite framework. Analysis of the potential energy indicates the major adsorption sites for mordenite and clinoptilolite, which are located in the largest cavities of the zeolites. The adsorption energy of the mordenite sites (1.52 eV) was larger than that of clinoptilolite (1.28 eV). The stronger attraction between the copper ions and mordenite sites is consistent with the lower diffusion coefficients of the ions in this zeolite. The ion-exchange abilities of the zeolites were examined using EDS analysis. According to the EDS results, the mordenite zeolite exchanged more copper ions than the clinoptilolite, which is in agreement with the computational results.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113397"},"PeriodicalIF":4.8,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573139","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}
Pub Date : 2024-10-28DOI: 10.1016/j.micromeso.2024.113395
Joseph Makela Nseke, John Kabuba, Iyiola Olatunji Otunniyi
Over the years, a wide range of cationic surfactants have been used for the modification of zeolite surface chemistry. In this research study, the synthesized surfactant modified zeolites were characterized using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), Fourier-transformed infrared spectroscopy (FTIR), Brunauer-Emmet-Teller (BET) and zeta potential analysis. Cr (VI) and Mo (VI). After modification, an increase in Cr (VI) and Mo (VI) oxyanion removal efficiency of zeolite 4A from 22.99 % to 96.3 % and 51.85 %–85.61 % has been observed. The pore volume diffusion and surface diffusion coefficients Dp and DS were in order of 10−12 cm2 s−1. The mass transfer coefficient Kf were in the order of 10−5 cm s−1. Cr (VI) and Mo (VI) adsorption on BZT-zeolite is good agreement with Langmuir and Sips models. The Cr (VI) and Mo (VI) uptake capacities are approximately equivalent to 3 mg/g. The highest enthalpy changes (ΔH°) for the removal of Cr (VI) and Mo (VI) were −105.429 and −53.243 kJ/mol respectively. The entropy changes (ΔS°) were −0.335 and −0.163 kJ/mol for the removal of Cr (VI) and Mo (VI) respectively. The free energies of adsorption of Cr (VI) and Mo (VI) were lower than zero. Hence, Cr (VI) and Mo (VI) adsorption process was found to be spontaneous and exothermic. ANN shows excellent modelling for the adsorption process with relatively error values lower than 10 %.
{"title":"Adsorption of selected oxyanions from aqueous solution using Benzethonium chloride modified zeolite 4A: Artificial neural network approach","authors":"Joseph Makela Nseke, John Kabuba, Iyiola Olatunji Otunniyi","doi":"10.1016/j.micromeso.2024.113395","DOIUrl":"10.1016/j.micromeso.2024.113395","url":null,"abstract":"<div><div>Over the years, a wide range of cationic surfactants have been used for the modification of zeolite surface chemistry. In this research study, the synthesized surfactant modified zeolites were characterized using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), Fourier-transformed infrared spectroscopy (FTIR), Brunauer-Emmet-Teller (BET) and zeta potential analysis. Cr (VI) and Mo (VI). After modification, an increase in Cr (VI) and Mo (VI) oxyanion removal efficiency of zeolite 4A from 22.99 % to 96.3 % and 51.85 %–85.61 % has been observed. The pore volume diffusion and surface diffusion coefficients D<sub>p</sub> and D<sub>S</sub> were in order of 10<sup>−12</sup> cm<sup>2</sup> s<sup>−1</sup>. The mass transfer coefficient Kf were in the order of 10<sup>−5</sup> cm s<sup>−1</sup>. Cr (VI) and Mo (VI) adsorption on BZT-zeolite is good agreement with Langmuir and Sips models. The Cr (VI) and Mo (VI) uptake capacities are approximately equivalent to 3 mg/g. The highest enthalpy changes (ΔH°) for the removal of Cr (VI) and Mo (VI) were −105.429 and −53.243 kJ/mol respectively. The entropy changes (ΔS°) were −0.335 and −0.163 kJ/mol for the removal of Cr (VI) and Mo (VI) respectively. The free energies of adsorption of Cr (VI) and Mo (VI) were lower than zero. Hence, Cr (VI) and Mo (VI) adsorption process was found to be spontaneous and exothermic. ANN shows excellent modelling for the adsorption process with relatively error values lower than 10 %.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"382 ","pages":"Article 113395"},"PeriodicalIF":4.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539493","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}
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