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TEPA-AM修饰的介孔材料吸附CO2性能的研究 总被引:1,自引:0,他引:1
将丙烯酰胺(AM)改性的四乙烯五胺(TE-PA)负载到介孔材料孔道内,形成氨基改性的CO2吸附材料。利用X射线衍射(XRD)、氮气物理吸附-脱附(BET)、红外等方法对样品进行了表征。通过动态吸附法研究了材料的CO2吸附和脱附性能,并与TEPA负载的吸附材料进行了比较。研究结果表明,在制备介孔分子筛MCM-41的过程中得到的一种结构规整度低的材料对TEPA-AM具有较好的分散性能,经过TE-PA-AM修饰的该材料表现出良好的CO2吸附性能,当TEPA-AM负载量达60%,该材料的吸附能力达到159.1mg/g;经过12次循环使用吸附量不下降。 相似文献
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介孔氧化铝因其在催化、吸附等领域具有巨大的应用前景,而受到国内外研究学者的广泛关注。随着工业化生产要求的不断提高,普通介孔氧化铝的使用逐渐受到限制,制备高性能的功能化介孔氧化铝材料将具有重大意义。功能化介孔氧化铝材料具有较高的催化活性、较强的机械和水热稳定性,不仅在催化、吸附领域受到极大重视,而且延伸到光学、医学等重要领域。综述了功能化介孔氧化铝材料的主要制备方法,包括原位合成法和浸渍法,并对两种方法存在的优缺点进行了比较。同时详细介绍了功能化介孔氧化铝材料的种类以及在催化、吸附分离和其它领域的应用,并展望了功能化介孔氧化铝材料的发展及应用前景。 相似文献
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两步晶化法制备介孔材料及其催化性能研究 总被引:1,自引:0,他引:1
采用两步晶化法,由MCM-22沸石前驱体合成了一种介孔材料.通过XRD、N2吸附-脱附、TEM、27A lMAS NMR以及吡啶吸附红外光谱等技术对样品进行了表征.结果显示所合成的样品不是微孔沸石与介孔材料的混合物,而是含强酸性中心、水热稳定性良好的新型介孔分子筛.利用异丙苯的裂解反应、苯和1-十二烯烃的烷基化反应,评价了其对大分子的酸催化活性,并与常规介孔材料MCM-41进行了比较.在350℃时,所合成的介孔材料和常规介孔材料MCM-41对异丙苯的裂解转化率分别为68.98%和48.80%.在210℃苯和1-十二烯烃的烷基化反应时,所合成的介孔材料和MCM-41对1-十二烯烃的转化率分别约为95.20%和86.89%,产物直链烷基苯的选择性分别约为88.11%和90.06%.结果表明所合成的介孔材料对大分子的酸催化性能优越于常规介孔材料MCM-41. 相似文献
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Ingemar Persson Joseph Halim Hans Lind Thomas W. Hansen Jakob B. Wagner Lars‐ke Nslund Vanya Darakchieva Justinas Palisaitis Johanna Rosen Per O. . Persson 《Advanced materials (Deerfield Beach, Fla.)》2019,31(2)
Global warming caused by burning of fossil fuels is indisputably one of mankind's greatest challenges in the 21st century. To reduce the ever‐increasing CO2 emissions released into the atmosphere, dry solid adsorbents with large surface‐to‐volume ratio such as carbonaceous materials, zeolites, and metal–organic frameworks have emerged as promising material candidates for capturing CO2. However, challenges remain because of limited CO2/N2 selectivity and long‐term stability. The effective adsorption of CO2 gas (≈12 mol kg?1) on individual sheets of 2D transition metal carbides (referred to as MXenes) is reported here. It is shown that exposure to N2 gas results in no adsorption, consistent with first‐principles calculations. The adsorption efficiency combined with the CO2/N2 selectivity, together with a chemical and thermal stability, identifies the archetype Ti3C2 MXene as a new material for carbon capture (CC) applications. 相似文献
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《Advanced Powder Technology》2019,30(12):3231-3240
In this study, a composite mesoporous silica material MCM-41 (Mobil composite matter) is impregnated with monoethanolamine (MEA) as primary linear amine, benzylamine (BZA) as primary cyclic amine and N-(2-aminoethyl) ethanolamine (AEEA) as secondary diamine and the effects of amine loading, amine type, CO2 partial pressure and adsorption temperatures on the CO2 adsorption are investigated. The CO2 adsorption performances of MCM-41 and amine impregnated MCM-41 samples are studied up to 1 bar of CO2 partial pressure and the temperature range of 25–60 °C. The amine loadings (% impregnation) are optimized for maximum CO2 uptake. The materials are characterised using N2 adsorption/desorption isotherm, Fourier Transform Infrared (FT-IR) Spectroscopy, Thermogravimetric (TGA) and Elemental (CHNS) analysis. The materials have shown good structural and thermal stability. The MCM-41-40%AEEA, MCM-41-40%BZA and MCM-41-50%MEA samples are exhibited the CO2 adsorption capacity of 2.34 mmol/g (102.98 mg/g), 0.908 mmol/g (39.96 mg/g) and 1.47 mmol/g (64.69 mg/g) respectively. The CO2 uptake of MCM-41-40%AEEA is 3.5 times higher than that of in MCM-41 (0.68 mmol/g) and it is also the highest reported value as di-amine impregnated MCM-41. The results indicated that the adsorption capacities of the materials (MCM-41 and MCM-41-40%AEEA) are decreased with an increase of adsorption temperature in the range of 25–60 °C. The Freundlich, Langmuir, Sips and Toth isotherm models are used to correlate and predict experimental CO2 adsorption data. The Sips and Toth isotherm models are found to be better fitted with the experimental data. The isosteric heat of adsorption of MCM-41 and MCM-41-40%AEEA samples are also calculated from Van’t Hoff plot using iSorbHP-win instrumental analysis software in the experimental temperature range. 相似文献
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Liangliang Zhang Yumeng Liu Tao Wang Zhilin Liu Wei Li Zhen-An Qiao 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(3):2205693
Two-dimensional (2D) mesoporous polymers, combining the advantages of organic polymers, porous materials, and 2D materials, have received great attention in adsorption, catalysis, and energy storage. However, the synthesis of 2D mesoporous polymers is not only challenged by the complex 2D structure construction, but also by the low yield and difficulty in controlling the dynamics of the assembly during the generation of mesopores. Herein, a facile multi-dimensional molecular self-assembly strategy is reported for the preparation of 2D mesoporous polydiaminopyridines (MPDAPs), which features tunable pore sizes (17–35 nm) and abundant N content up to 18.0 at%. Benefitting from the abundant N sites, 2D nanostructure, and uniform-large mesopores, the 2D MPDAPs exhibit excellent catalytic performance for the Knoevenagel condensation reaction. After calcination under N2 atmosphere, the obtained 2D N-doped mesoporous carbon (NMCs) with large and uniform pore sizes, high surface areas, abundant N content (up to 23.1%), and a high ratio of basic N species (57.0% pyridinic N and 35.9% pyrrolic N) can show an excellent CO2 uptake density (11.7 µmol m−2 at 273 K), higher than previously reported porous materials. 相似文献
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Han-Kyol YounJun Kim Govindasamy ChandrasekarHangkyo Jin Wha-Seung Ahn 《Materials Letters》2011,65(12):1772-1774
Nanoporous carbons were synthesized by chemical vapor deposition using furfuryl alcohol/butylene as a carbon source and zeolite Y as a hard template (ZYC). The ZYC were characterized by PXRD, N2 sorption, and SEM. The carbon materials exhibited predominant microporosity, and the specific surface area increased from 2563 to 3010 m2 g−1 as the pyrolysis temperature was raised from 800 to 1000 °C. ZYC prepared at 1000 °C showed a CO2 adsorption capacity of 986 mg g−1adsorbent at 40 bar 298 K, which surpasses the capacities of commercial carbons and mesoporous carbon CMK-3, and closely approaches the best performance of the metal organic framework MOF-177. The CO2 adsorption capacities of the adsorbents were found to be closely correlated with the BET surface areas of the materials tested. 相似文献
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Porous carbon materials were prepared by hydrothermal carbonization(HTC) and KOH activation of camphor leaves and camellia leaves. The morphology, pore structure, chemical properties and CO_2 capture ability of the porous carbon prepared from the two leaves were compared. The effect of HTC temperature on the structure and CO_2 adsorption properties was especially investigated. It was found that HTC temperature had a major effect on the structure of the product and the ability to capture CO_2. The porous carbon materials prepared from camellia leaves at the HTC temperature of 240℃ had the highest proportion of microporous structure, the largest specific surface area(up to 1823.77 m~2/g) and the maximum CO_2 adsorption capacity of 8.30 mmol/g at 25℃ under 0.4 MPa. For all prepared porous carbons, simulation results of isothermal adsorption model showed that Langmuir isotherm model described the adsorption equilibrium data better than Freundlich isotherm model. For porous carbons prepared from camphor leaves, pseudo-first order kinetic model was well fitted with the experimental data. However,for porous carbons prepared from camellia leaves, both pseudo-first and pseudo-second order kinetics model adsorption behaviors were present. The porous carbon materials prepared from tree leaves provided a feasible option for CO_2 capture with low cost, environmental friendship and high capture capability. 相似文献
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Danhua Song Feilong Jiang Daqiang Yuan Qihui Chen Maochun Hong 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(44):2302677
Excessive CO2 in the air can not only lead to serious climate problems but also cause serious damage to humans in confined spaces. Here, a novel metal–organic framework (FJI-H38) with adaptive ultramicropores and multiple active sites is prepared. It can sieve CO2 from air with the very high adsorption capacity/selectivity but the lowest adsorption enthalpy among the reported physical adsorbents. Such excellent adsorption performances can be retained even at high humidity. Mechanistic studies show that the polar ultramicropore is very suitable for molecular sieving of CO2 from N2, and the distinguishable adsorption sites for H2O and CO2 enable them to be co-adsorbed. Notably, the adsorbed-CO2-driven pore shrinkage can further promote CO2 capture while the adsorbed-H2O-induced phase transitions in turn inhibit H2O adsorption. Moreover, FJI-H38 has excellent stability and recyclability and can be synthesized on a large scale, making it a practical trace CO2 adsorbent. This will provide a new strategy for developing practical adsorbents for CO2 capture from the air. 相似文献
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Valuing Metal–Organic Frameworks for Postcombustion Carbon Capture: A Benchmark Study for Evaluating Physical Adsorbents
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Karim Adil Prashant M. Bhatt Youssef Belmabkhout Sk Md Towsif Abtab Hao Jiang Ayalew H. Assen Arijit Mallick Amandine Cadiau Jamal Aqil Mohamed Eddaoudi 《Advanced materials (Deerfield Beach, Fla.)》2017,29(39)
The development of practical solutions for the energy‐efficient capture of carbon dioxide is of prime importance and continues to attract intensive research interest. Conceivably, the implementation of adsorption‐based processes using different cycling modes, e.g., pressure‐swing adsorption or temperature‐swing adsorption, offers great prospects to address this challenge. Practically, the successful deployment of practical adsorption‐based technologies depends on the development of made‐to‐order adsorbents expressing mutually two compulsory requisites: i) high selectivity/affinity for CO2 and ii) excellent chemical stability in the presence of impurities. This study presents a new comprehensive experimental protocol apposite for assessing the prospects of a given physical adsorbent for carbon capture under flue gas stream conditions. The protocol permits: i) the baseline performance of commercial adsorbents such as zeolite 13X, activated carbon versus liquid amine scrubbing to be ascertained, and ii) a standardized evaluation of the best reported metal–organic framework (MOF) materials for carbon dioxide capture from flue gas to be undertaken. This extensive study corroborates the exceptional CO2 capture performance of the recently isolated second‐generation fluorinated MOF material, NbOFFIVE ‐1‐Ni, concomitant with an impressive chemical stability and a low energy for regeneration. Essentially, the NbOFFIVE ‐1‐Ni adsorbent presents the best compromise by satisfying all the required metrics for efficient CO2 scrubbing. 相似文献
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Carbon Dioxide Promotes Dehydrogenation in the Equimolar C2H2‐CO2 Reaction to Synthesize Carbon Nanotubes
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Wenbo Shi Yue Peng Stephen A. Steiner III Junhua Li Desiree L. Plata 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(11)
The equimolar C2H2‐CO2 reaction has shown promise for carbon nanotube (CNT) production at low temperatures and on diverse functional substrate materials; however, the electron‐pushing mechanism of this reaction is not well demonstrated. Here, the role of CO2 is explored experimentally and theoretically. In particular, 13C labeling of CO2 demonstrates that CO2 is not an important C source in CNT growth by thermal catalytic chemical vapor deposition. Consistent with this experimental finding, the adsorption behaviors of C2H2 and CO2 on a graphene‐like lattice via density functional theory calculations reveal that the binding energies of C2H2 are markedly higher than that of CO2, suggesting the former is more likely to incorporate into CNT structure. Further, H‐abstraction by CO2 from the active CNT growth edge would be favored, ultimately forming CO and H2O. These results support that the commonly observed, promoting role of CO2 in CNT growth is due to a CO2‐assisted dehydrogenation mechanism. 相似文献
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AbstractWe report the advances in the principal structural and experimental factors that might influence the carbon dioxide (CO2) adsorption on natural and synthetic zeolites. The CO2 adsorption is principally govern by the inclusion of exchangeable cations (countercations) within the cavities of zeolites, which induce basicity and an electric field, two key parameters for CO2 adsorption. More specifically, these two parameters vary with diverse factors including the nature, distribution and number of exchangeable cations. The structure of framework also determines CO2 adsorption on zeolites by influencing the basicity and electric field in their cavities. In fact, the basicity and electric field usually vary inversely with the Si/Al ratio. Furthermore, the CO2 adsorption might be limited by the size of pores within zeolites and by the carbonates formation during the CO2 chemisorption. The polarity of molecules adsorbed on zeolites represents a very important factor that influences their interaction with the electric field. The adsorbates that have the most great quadrupole moment such as the CO2, might interact strongly with the electric field of zeolites and this favors their adsorption. The pressure, temperature and presence of water seem to be the most important experimental conditions that influence the adsorption of CO2. The CO2 adsorption increases with the gas phase pressure and decreases with the rise of temperature. The presence of water significantly decreases adsorption capacity of cationic zeolites by decreasing strength and heterogeneity of the electric field and by favoring the formation of bicarbonates. The optimization of the zeolites structural characteristics and the experimental conditions might enhance substantially their CO2 adsorption capacity and thereby might give rise to the excellent adsorbents that may be used to capturing the industrial emissions of CO2. 相似文献