共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
沸石咪唑酯骨架结构材料(ZIFs)是一类以咪唑或其衍生物为配体的特殊金属有机骨架结构材料(MOFs),因其结构多样性、高度的热学和化学稳定性及高效捕获和存储CO2等性能,近几年受到国内外研究者的广泛关注。本文对含咪唑基配体材料的合成和发展现状进行了综述;总结了这种材料在气体的存储和分离、磁性、催化等方面的性能,并对这种新型材料在设计、合成与应用中的广阔前景作了展望。 相似文献
4.
金属-有机骨架材料制备及其吸附净化挥发性有机物应用 总被引:1,自引:0,他引:1
吸附技术是控制净化挥发性有机化合物(Volatile Organic Compounds,VOCs)常用且有效的方法之一,其核心和关键是具有高比表面积和孔容的高效吸附材料。金属-有机骨架材料(Metal-Organic Frameworks,MOFs)是一类具有超高比表面积和孔容的新型高效吸附材料,在VOCs吸附净化领域具有广阔的应用前景。概述了MOFs材料的发展历程,重点介绍了MOFs材料合成制备方法及其对VOCs的吸附研究进展,讨论了相关研究工作尚存在的科学技术问题并展望了未来研究方向。 相似文献
5.
气体分离在石油化工和化工生产中有非常重要的作用。沸石咪唑酯骨架(ZIFs)作为一种新型的多孔材料,具有大比表面积、高孔隙率、多样的结构组成和超高的热稳定及化学稳定性,成为该领域的研究热点。本文围绕ZIFs材料的合成展开,详尽地总结了现阶段ZIFs在气体吸附分离领域的应用,重点介绍ZIFs在工业CO2捕获及分离、轻质烃分离、气相色谱分离、用于气体分离的ZIFs基膜、惰性气体分离和有毒气体分离等行业的研究进展。同时指出,ZIFs材料在气体吸附分离领域的应用仍需要进一步研究,如新型低成本配体的开发、探索更多的合成方法来调整晶体结构、提升ZIFs材料的吸附效率,才能使ZIFs从实验室走向工业化。 相似文献
7.
8.
综述了微反应器的优点以及运用沸石及其膜组装微型反应器的制备方法、研究进展及应用前景.分析了沸石及其膜组装微型器件的类型、制备和应用,重点讨论了沸石在微型设备中的组装制备方法、特点和沸石及其膜反应器良好的应用开发潜力. 相似文献
9.
10.
类沸石咪唑酯骨架材料(ZIFs)的研究进展 总被引:1,自引:0,他引:1
类沸石咪唑酯骨架化合物(zeolitic imidazolate frameworks,ZIFs)是一种新型的MOFs材料,ZIFs是将咪唑环上的N原子络合到二价过渡金属离子上而形成的一种具有沸石拓扑结构的多孔晶体材料,通过调变配体或配体间的相互作用就可以形成不同结构的ZIFs。ZIFs的合成方法包括溶剂热法、水热法、液相扩散法、胶体化学法、微波合成法和超声法等,本文综述了ZIFs材料的多种优异性能,介绍了近些年来ZIFs材料在选择性气体吸附/分离、催化反应、光学、磁性材料及其他方面的应用。最后对合成新型的ZIFs材料,并将该ZIFs材料应用在电子设备、能源利用以及环境保护等方面进行了展望。 相似文献
11.
Jiaqi Liu Xuan Tang Xiaowu Liang Luogang Wu Feifei Zhang Qi Shi Jiangfeng Yang Jinxiang Dong Jinping Li 《American Institute of Chemical Engineers》2022,68(5):e17589
Various adsorbents for CH4/N2 separation were developed to enrich low-concentration coal-mine methane. Most are hydrophilic and cannot treat moist coal-mine methane. We report for the first time a microporous zeolitic imidazolate framework Co(dcIm)2 (TUT-100) with superhydrophobic properties for CH4/N2 separation. The CH4 adsorption capacity and CH4/N2 selectivity were as high as 45.29 cm3/cm3 and 6.3 (298 K, 1 bar), respectively, which results from the suitable SOD cage size (0.80 nm). The H2O adsorption was lower than 6.3 cm3/g at 298 K and near saturated pressure due to the hydrophobic group Cl. Breakthrough experiments were carried out to indicate the significant potential for CH4/N2 adsorption separation in a humid environment. The adsorption behavior of the gas mixture on the TUT-100 was investigated by the Grand Canonical Monte Carlo method and coupled with the experimental data. 相似文献
12.
与对称膜、非对称膜相比,渗透蒸发复合膜有扩散阻力小、渗透通量高、机械强度好等优点,同时在选材和制备方面也有其自身的特点。活性层材料主要依据Flory huggins相互作用参数理论或溶解度参数理论进行粗略选择,再通过一些实验手段做进一步筛选。支撑层材料多为无机或有机多孔材料,选择的主要依据是材料的物理化学性质、机械性质及结构。另外,活性层与支撑层之间的黏合与孔渗也是必须考虑的问题。介绍了相关的黏合理论,列举了常用的防止孔渗发生的措施。最后结合近年来渗透蒸发复合膜的研究实例详细介绍了复合膜的常用制备方法,如界面聚合法、浸涂法、等离子聚合法和自组装法等。 相似文献
13.
采用分子模拟的方法模拟77 K下N2在沸石咪唑骨架材料(ZIFs)上的吸附等温线,并与实验结果比较,确定合适的力场参数,提供用BET方法分析ZIFs材料比表面积的吸附等温线。通过BET吸附方程中的参数c与单层吸附压力(p/p0)m之间的关系为(p/p0)m=(槡c+1)-1,确定应用BET方程分析时的压力区间。采用这样的方法计算5种ZIF材料的比表面积并与根据一致性原则(Rouquerol,2007)的结果进行比较,结果表明方法是可靠的,这说明采用合适的压力区间时,BET方法同样适用于分析微孔ZIF材料的比表面积。计算得到的5种ZIF材料比表面积均在1 000 m2/g以上,说明ZIF材料是一种具有高比表面积、有应用前景的吸附材料。 相似文献
14.
Mixed matrix membranes (MMMs), which combine the good separation performance of inorganic materials with the low cost of polymers, have emerged as a research hotspot for gas separation membranes. Zeolite imidazolate frameworks (ZIFs) are widely used as fillers to prepare MMMs owing to their advantageous characteristics, such as adjustable pore channels, unsaturated sites, and easy functionalization. For MMMs, three directions can be employed as criteria for improvement compared with pristine polymeric membranes. In this article, the progress of ZIF-based MMMs is reviewed from the aspects of sole-ZIF-based MMMs and modified ZIF-based MMMs. Both strategies improve the separation performance through different improvement directions and mechanisms. Our analysis shows that the synergistic effect of the modified filler can change the structure of the membranes, such as by improving the filler–polymer interface voids, which provides a foundation to overcome the trade-off effect to a certain extent. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48968. 相似文献
15.
Ihtisham Ul Haq Tao Wang Ao-Shuai Zhang Heng Mao Rehan Khan Li-Hao Xu Zhi-Ping Zhao 《American Institute of Chemical Engineers》2021,67(4):e17114
1,3-Butadiene (BD) is a petrochemical-based volatile organic compound, extensively used for the manufacture of synthetic rubber. There is no method reported for its recovery from nitrogen mixture. Herein, for the first time, BD is efficiently recovered by gas separation through facile and novel mixed-metal ZIF-8 based mixed matrix membranes (MMMs). Addition of Ni-ZIF-8 nanoparticles in PDMS matrix, significantly improved the penetrant-membrane interactions and the solution-diffusion properties of BD. Positron annihilation lifetime spectroscopy analysis showed that the well dispersion of Ni-ZIF-8 in PDMS enhanced the free volume of membrane and created efficient continuous paths for BD diffusion. Then, 15 wt% Ni-ZIF-8 MMM exhibited the BD permeance of 323 GPU and the BD/N2 ideal selectivity of 19.5, which were 60 and 81% higher than pure PDMS membrane, respectively. The simultaneous enhancement of BD permeance and BD/N2 ideal selectivity indicated that Ni-ZIF-8 was an effective filler applied in MMMs for efficient BD recovery. 相似文献
16.
Xinlei Liu 《Frontiers of Chemical Science and Engineering》2020,14(2):216
Metal-organic frameworks (MOFs) have emerged as a class of promising membrane materials. UiO-66 is a prototypical and stable MOF material with a number of analogues. In this article, we review five approaches for fabricating UiO-66 polycrystalline membranes including in situ synthesis, secondary synthesis, biphase synthesis, gas-phase deposition and electrochemical deposition, as well as their applications in gas separation, pervaporation, nanofiltration and ion separation. On this basis, we propose possible methods for scalable synthesis of UiO-66 membranes and their potential separation applications in the future. 相似文献
17.
膜分离技术因其高效节能的特点,被认为是最有前景的分离技术之一。由于众多待分离的混合组分在物理性质(如尺寸)上极为接近,实现精确的膜分离仍具有极大的挑战。金属有机骨架材料具有孔径精确可调、孔隙率高等优点,使其有望实现对尺寸相近分子的精确筛分,因此可以作为理想的膜材料。本文对传统的多孔膜材料进行了比较,并对基于金属有机骨架材料的多孔膜进行了分类,包括支撑型金属有机骨架膜和混合基质膜。同时,系统地总结了两大类金属有机骨架膜的制备方法及其发展历程,对先进的膜制备技术进行了展望;总结了金属有机骨架膜在气体分离、纳滤及海水淡化、渗透汽化等方面的应用。最后,针对支撑型金属有机骨架膜提出了改善其透量和选择性的思路。 相似文献
18.
Hailong Wang Neng Li Zhongbo Hu Thomas D. Bennett Xiujian Zhao Wai-Yim Ching 《Journal of the American Ceramic Society》2019,102(8):4602-4611
The amorphous zeolitic imidazolate frameworks (a-ZIFs) models and its analogues (with 918 or 810 atoms, respectively) are constructed based on a larger continuous random network (CRN) model of amorphous SiO2 (a-SiO2) model. The atomic, electronic, and dielectric properties of these structures, which possess different metal nodes and organic linkers, are investigated by well-defined density functional theory (DFT) calculations. The results suggest that all a-ZIFs have ultra-low dielectric constants and a large energy loss function (ELF), which suggests that they may be good candidates for electromagnetic absorptive materials. Most important, these a-ZIFs models offer a base-line model for other amorphous ZIFs for further research on models containing vacancies, defects, doping or under high pressure or high temperature. 相似文献
19.
20.
Zeolitic imidazolate framework-8 (ZIF-8) was synthesized at room temperature, and then added with expandable graphite (EG) to polyurethane elastomer (PUE) to study their flame retardancy and smoke suppression of PUE. The results showed that when the total flame retardant was 3 wt % and the ratio of ZIF-8 and EG was 1:3, it had the best effect on the flame retardancy and smoke suppression of PUE. Compared with pure PUE, the peak heat release rate, the total heat release, and the maximum smoke density values of Z1E3 decreased by 83.4, 42.6, and 22.4%, respectively. Moreover, the limited oxygen index value of Z1E3 increased to 30.2% and its UL-94 vertical burning test reached V-1 rating. This was because ZIF-8 synergized with EG to make the intumescent char layer compact, resulting in improved flame retardancy and smoke suppression of PUE. The specific mechanism of flame retardancy and smoke suppression is also discussed in this article. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48048. 相似文献