MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
Yanyong Sun,Minmin Gou
Based on the one-dimensional tubular structure of halloysite nanotubes (HNTs), plant polyphenols and polyamines were used for in situ polymerization on the surface of HNTs to form amino-rich polymers, which were then removed as templates to synthesize polymer nanotubes. These nanotubes were then incorporated into a Pebax matrix to prepare mixed-matrix membranes (MMMs) for CO 2 /CH 4 gas separation. The removal of the HNT template increased the lumen diameter of the filler and significantly improved its gas permeability . And the amino groups on the inner surface of the polymer nanotubes were exposed. Further, the number of CO 2 reaction sites increased, which improved the reaction selectivity of CO 2 . In addition, the presence of amine groups on the inner and outer surfaces of the polymer nanotubes provided various transfer channels for CO 2 , which were conducive for CO 2 gas transfer in the membrane. When the CC-PEINT content was 8 wt%, the CO 2 permeability was 710 Barrer and CO 2 /CH 4 selectivity was 60. The CO 2 permeability and CO 2 /CH 4 selectivity of the Pebax/CC-PEINTs membranes increased by 163% and 132%, respectively, compared with those of the pure Pebax membrane.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Tongxin Liu,Ruili Zhang,Guangcan Huang,Yabo Xie,Lin-Hua Xie,Jian-Rong Li
Emerging as a new type of porous materials, metal-organic cages (MOCs) show great potential in adsorption and separation. The high porosity and solubility of MOCs have generated increasing interest in their use as fillers for preparing mixed matrix membranes (MMMs). Herein, we present a series of zirconocene-based MOCs (MOC-1, MOC-1-NH 2 , and MOC-1-4F), which were used to fabricate MMMs with polyimide 6FDA-DAM. Particularly, the perfluorinated MOC (MOC-1-4F) could form a clear casting solution with 6FDA-DAM in some solvents. The resultant MMMs were analyzed by AFM, SEM, EDX-mapping, XRD, CSM, Raman, TG, and DSC measurements, indicating that MOC-1-4F were homogeneously dispersed in 6FDA-DAM, and the T g values, mechanical property, CO 2 solubility and diffusivity of the membrane were promoted after the introduction of MOC-1-4F. The MOC-1-4F based membranes also outperformed the membranes with MOC-1 or MOC-1-NH 2 as filler in CO 2 /CH 4 separation. A low MOC-1-4F loaded MMM (MOC-1-4F-2.17%) exhibited 57% improved CO 2 permeability (1228 barrer) in comparison with 6FDA-DAM membrane, and the CO 2 /CH 4 selectivity reached 22, surpassing the 2008 Robeson upper-bound. The plasticization effect was significantly alleviated in MOC-1-4F-2.17%, indicating that the MOC-1-4F-2.17% is potential for CO 2 /CH 4 separation. This work demonstrates that the gas separation performance of MOC-based MMMs could be fine-tuned by the structural tailoring of MOCs.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Xianglei Liu,Zekai Mu,Chen Sun,Hang Shi,Xianguang Meng,Ping Li,Yueyue Ling,Bo Cheng,Yimin Xuan,Yulong Ding
Solar-driven CO 2 reduction by CH 4 is promising to simultaneously tackle energy shortage and global warming problems by converting two greenhouse gases into fuels. However, serious challenges remain, such as limited light-to-fuel efficiency, high operating temperature, and severe catalyst deactivation. Here, high-performance direct solar-driven CO 2 reduction is demonstrated at relatively low operation temperature (594 °C) based on NiCo-ZIF derived nanostructures. An ultrahigh light-to-fuel efficiency of 32.4% and production rates of H 2 (105.83 min −1 g −1 ) and CO (128.17 mmol min −1 g −1 ) are achieved via photothermocatalysis on Ni 1 Co 2 @C ZIF -Al 2 O 3 catalysts. Excellent light-to-fuel conversion performance can be attributed to the highly dispersed metal particles, decreased apparent activation energy under direct light illumination, increased CO 2 absorption, and promoted dissociation of CH 4 to CH 3 * of NiCo alloy. The carbon deposition rate of NiCo bimetallic catalysts is prominently inhibited compared with pure Ni or Co catalysts due to the change of the reaction path, as confirmed by DFT calculations. This work opens new routes to achieve highly efficient solar-driven CO 2 reduction by CH 4 based on NiCo-ZIF derived alloy nanostructures at relatively low-temperature conditions.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Wei Xie,Yang Jiao,Zhili Cai,Hongyan Liu,Lili Gong,Wei Lai,Linglong Shan,Shuangjiang Luo
This paper reports two new series of benzimidazole functionalized polyimides and ionic polyimides for highly selective membranes with great potential for natural gas sweetening. It has been demonstrated that both the –NH groups in the benzimidazole moieties and the corresponding ionic groups after N -quaternization tighten the microporous structure and restrict polymer chain mobility through hydrogen bonding and electrostatic interaction. The BET surface areas and d -spacing values decrease with benzimidazole molar content or the degree of ionization. Consequently, a linear correlation between CO 2 permeability coefficients with benzimidazole molar content or degree of ionization was observed due to the decrease of CO 2 diffusivity, and the monotonic increase of CO 2 /CH 4 selectivities is ascribed to the increase of both diffusivity selectivity and solubility selectivity. The benzimidazole-based copolyimide and the ionic copolyimide membranes exhibited high CO 2 /CH 4 selectivity under high-pressure mixed-gas conditions. In particular, the copolyimide PI-0.75 membrane displayed a mixed-gas CO 2 permeability of 27 Barrer and CO 2 /CH 4 selectivity of 47 at 20 bar total pressure. The performance was much higher than those of the state-of-the-art commercial cellulose triacetate membranes for natural gas upgrading. The facile polymer synthesis and microporosity tunability, as well as the excellent mixed-gas separation performance, render the copolyimide membranes in this study promising towards economic membrane-mediated natural gas upgrading.
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2021
·Vol. 67
·期 9
·e17281
·
IF 3.993
Ze Dong,Bei Li,Hua Shang,Peixin Zhang,Shixia Chen,Jiangfeng Yang,Zheling Zeng,Jun Wang,Shuguang Deng
The adsorptive separation of CH 4 from low-grade coal-bed gas can be performed at decentralized and remote coal mines, and it uses more energy- and is cost-efficient than the traditional cryogenic distillation process. Herein, we present a facile method to prepare ultramicroporous carbon granules with a narrow pore-size distribution at 0.5–0.6 nm. To our knowledge, such centered and uniform pore-size distribution in carbon granules has never been reported. The carbon granules can be directly utilized in adsorption columns without a granulation or pelletization process. The granular oil-tea-shell-derived porous carbon (GOC-2) exhibited a record-high CH 4 uptake of 1.82 mmol/g and CH 4 /N 2 selectivity of 5.8 at 1.0 bar and 298 K among carbon granules. The excellent CH 4 /N 2 separation performances were confirmed from the results of dynamic breakthrough experiments and pressure swing adsorption simulations. This work provides a novel strategy for developing ultramicroporous carbon granules and guides the future design of efficient CH 4 /N 2 separation adsorbents.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Natural Gas Science and Engineering
·
2021
·
IF 4.965
Xiangyu Cai,Ye Yuan,Menglong Sheng,Jixiao Wang,Zhi Wang
The polyvinylamine (PVAm) was respectively modified by the MOFs (IRMOF-3 and ZIF-8) with amine groups that were characterized by TEM, SEM and XRD . The PVAm-MOFs/polysulfone (mPSf) mixed matrix membranes (MMMs) were fabricated by coating different PVAm-MOFs mixtures on mPSf ultrafiltration membranes. The performance of the PVAm-MOFs/mPSf and PVAm/mPSf membranes for CO 2 /CH 4 separation was investigated. Compared with the PVAm/mPSf virgin membrane, PVAm-MOFs/mPSf MMMs display higher CO 2 separation performance due to the decreased membrane effective thickness and incorporation of amine-rich nanochannels. Furthermore, compared with PVAm-ZIF-8/mPSf MMM, the PVAm-IRMOF-3/mPSf MMM possesses higher CO 2 /CH 4 separation performance. Then the CO 2 /CH 4 separation performance of the PVAm-IRMOF-3/mPSf MMMs with different IRMOF-3 loadings was studied. Compared with other reported membranes, the PVAm-IRMOF-3/mPSf MMM loaded 25 wt% IRMOF-3 shows higher CO 2 /CH 4 separation performance at both low and high feed pressure.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Minmin Gou,Weifang Zhu,Yanyong Sun,Ruili Guo
Two-dimensional (2D) MOF named Cu(BPY) 2 (OTF) 2 (OTF = trifluoromethanesulfonic acid anion (CF 3 SO 3 − ), BPY = 4,4-bipyridine) possessing axial coordination anion was prepared, and then combined into Pebax® MH 1657 (Pebax) polymer to fabricate mixed matrix membranes (MMMs) for the separation of CO 2 /CH 4 gas mixtures. The inherent microporous structure and interlayer nanochannel that constructed by axial coordination anion CF 3 SO 3 − of Cu(BPY) 2 (OTF) 2 nanosheets provide selective transfer channels for CO 2 . In addition, the group that has an affinity for CO 2 , such as pyridine group and CF 3 SO 3 − anion, locating in the surface and the interlayer of Cu(BPY) 2 (OTF) 2 nanosheets, present better binding affinity and molecule selectivity for CO 2 . Owing to the synergistic effect between structure and functional groups of Cu(BPY) 2 (OTF) 2 nanosheets, the optimized CO 2 separation performance (permeability and selectivity) of the MMMs compared with that of pure Pebax were increased by 86.65% and 47.59%, respectively, under the conditions of pure gas, 0.1 MPa and 25 °C. The open narrow nanochannels and axial coordination anion in Cu(BPY) 2 (OTF) 2 nanosheet, making Cu(BPY) 2 (OTF) 2 a promising material to prepare efficient mixed matrix membrane.
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Yong Guo,Wei Xiao,Wanfen Pu,Jun Hu,Jinzhou Zhao,Lijuan Zhang
The surface hydrophobicity of solid particles plays a critical role in the nucleation of gas hydrate formation, and it was found that the hydrophobic surface will promote this nucleation process, but the underlying mechanism is still unveiled. Herein, we proposed for the first time our new theory that the formation of methane nanoscale gas bubbles on the hydrophobic surface provides the nuclei sites for further formation of methane hydrate. First, we studied the effect of hydrophobicity of particles on the nucleation of hydrate. It was found that the hydrophobic graphite and silica particles would promote the nucleation of hydrate, but the hydrophilic silica particles did not promote the methane hydrate nucleation. Then, we designed the atomic force microscopy experiment to explain this mechanism from a nanometer scale. The results showed that the methane nanobubbles were formed on the hydrophobic highly ordered pyrolytic graphite surface, but they were hard to form on the hydrophilic mica surface. These results indicated that the methane nanobubbles on the hydrophobic surface could provide the gas hydrate nucleation sites and may induce a rapid nucleation of methane hydrate.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
·
2014
·
IF 1.178
Wei Wang,Ye Yuan,Fu-Xing Sun,Guang-Shan Zhu
Novel porous aromatic frameworks (PAF-53 and PAF-54) have been obtained by the polymerization of amino compound ( p -phenylenediamine and melamine) and cyanuric chloride. They display a certain amount of CO 2 adsorption capacity and highly selective separation of CO 2 /CH 4 and CO 2 /N 2 as 18.1 and 83 by Henry Law respectively. They may be applied as ideal adsorbents to separate and capture CO 2 .
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Zhiqiao He,Juntao Tang,Jie Shen,Jianmeng Chen,Shuang Song
TiO 2 nanosheets modified with various concentrations of sulfuric acid have been synthesized through hydrothermal treatment at 240 °C followed by heat treatment at 105 °C. Compared with untreated TiO 2 nanosheets, the H 2 SO 4 -modified samples exhibited markedly improved quantum yield (QY), energy returned on energy invested (EROEI), and turnover number (TON) for CO 2 reduction to CH 4 under visible-light irradiation. As supported by physical-chemical characterization, the enhanced photocatalytic activities can be attributed to acidification promoting the formation of hydroxyl groups (Brønsted acidic sites) and oxygen vacancies/Ti 3+ species. Thus, efficient charge separation and transfer to the TiO 2 surface for both CO 2 reduction and the accompanying H 2 O oxidation is facilitated. The highest activity for CO 2 photoreduction to CH 4 was obtained with TiO 2 nanosheets with 0.5 mol L −1 H 2 SO 4 , with QY, EROEI, and TON of 0.726‰, 0.335‰, and 83.124, respectively. Furthermore, the catalyst maintained stable performance throughout five successive recyclability test runs.
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 7
·2957-2963
·
IF 3.5
Peng Zhang,Sai Ma,Yujuan Zhang,Chaohui He,Tuoping Hu
The energy-saving separation of CO2/N2 and CH4/N2 in the energy industry facilitates the reduction of greenhouse gas emissions and replenishes energy resources, but is a challenging separation process. The trade-off between adsorption capacity and selectivity of the adsorbents is one of the key bottlenecks in adsorption separation technologies’ large-scale application in the above separation task. Herein, we introduced a series of fluoroborate or fluorosilicate salts (Cu(BF4)2, Zn(BF4)2 and ZnSiF6) into the open coordination nitrogen sites of aluminum-based metal–organic frameworks (MOF-253) to create multiple binding sites to simultaneously enhance the adsorption capacity and selectivity for the target gas. By the synergistic adsorption effect of metal ions (Cu2+ or Zn2+) and fluorinated anions (BF4− or (SiF6)2−), the single-component adsorption capacity and selectivity of salt-modified MOF-253 (MOF-253@Cu(BF4)2, MOF-253@Zn(BF4)2 and MOF-253@ZnSiF6) for CO2 and CH4 were effectively improved when compared to pristine MOF-253 at 298 K and 1 bar. In addition, the salt-modified MOF-253 has a moderate adsorption heat (<30 kJ mol−1) which could be rapidly regenerated at low energy by evacuation desorption. As confirmed by the ambient breakthrough experiments of MOF-253 and MOF-253@ZnSiF6, the real separation performance for both CO2/N2 (1/4) and CH4/N2 (1/4) was obviously improved. This work provides a feasible post-modification strategy on uncoordinated sites of the framework to improve adsorption separation performance and promote the development of ideal adsorbents with a view to realizing their application in the energy industry.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiawu Huang,Cuiting Yang,Shengjun Du,Lin Zhu,Zhenglin Du,Guang Miao,Chunshan Song,Jing Xiao
Adsorption-based capture of carbon dioxide (CO 2 ) to upgrade natural gas offer a promising solution for energy crisis and the reduction of CO 2 emission. However, trade-off between high adsorption selectivity and rapid kinetic is an inherent shortcoming of size-sieving based adsorptive separation of gas molecules at similar sizes, hindering the launch of sieving adsorbent for practical challenging selective gas capture. Herein, a gradiently porous carbon nanofiber PCF-800 with interconnected sieving ultramicropores and low-proportion surficial mesopores is tailor-made to simultaneously realize the exclusive and rapid capture of CO 2 from CH 4 . Arising from the unique interconnected micro-mesoporous structure, the as-prepared PCF-800 not only achieves remarkable uptake ratio of 45 (298 K, 1 bar) for CO 2 /CH 4 separation via size-sieving effect but also shows fast kinetic with diffusion rate of 1.35 × 10 -3 s −1 , outperforming the conventional ultramicroporous counterpart. Moreover, the impressive dynamic CO 2 /CH 4 separation factor up to 21.7 and satisfying cycling durability revealed by the breakthrough experiments further imply the industrial potential of PCF-800 in practical CH 4 purification. This work may shed light on the design of gradient sieving carbonaceous adsorbent with high selectivity and fast kinetic for extensive high-performance small gas separation.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）