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1.
The increase in CO2 concentration in the atmosphere has led to global warming, which draws great attention all over the world. Adsorption is considered as an effective method for CO2 capture and stabilizing the increasing CO2 concentration. Metal–organic frameworks (MOFs) are promising materials for carbon capture. However, the direct use of MOF powders may lead to issues such as high pressure drop, pipe clogging, and handling difficulties in applications. Herein, a phase inversion strategy is reported to prepare SIFSIX-3-Ni@PAN composite beads. The prepared composites exhibit hierarchically porous structure with uniform MOF distribution inside the materials and good mechanical stability. The MOF content can be well controlled and composites with up to 70% loading are prepared. Finally, the obtained materials possess high CO2 capture capacity, even at low CO2 concentrations (1.19 mmol g−1 at 0.01 bar and 298 K).  相似文献   

2.
We review the design and use of microporous polymers for pre‐ and post‐combustion capture of CO2. Microporous organic polymers are promising candidates for CO2 capture materials. They have good physicochemical stabilities and high surface areas. Ultrahigh‐surface‐area microporous organic polymers could find use in pre‐combustion capture, while networks with lower surface areas but higher heats of sorption for CO2 might be more relevant for lower pressure, post‐combustion capture. We discuss strategies for enhancing CO2 uptakes including increasing surface area, chemical functionalization to provide high‐enthalpy binding sites and the potential for pore size tuning. © 2013 Society of Chemical Industry  相似文献   

3.
A highly efficient and stable solid adsorbent invoking a direct incorporation of tetraethylenepentamine (TEPA) onto the as-synthesized mesocelullar silica foam (MSF) has been developed for CO2 capture. Unlike most amine-functionalized silicas, which typically exhibit CO2 adsorption capacities less than 2.0 mmol/g, such organic template occluded mesoporous silica-amine composites exhibited remarkably high CO2 uptake as high as 4.5 mmol/g at 348 K and 1 atm. Moreover, notable increases in CO2 adsorption capacities of the composite materials were observed when in the presence of humidity. Durability test performed by cyclic adsorption–desorption revealed that such adsorbents also possess excellent stability, even though a slight decrease in adsorption capacity over time was observed.  相似文献   

4.
The increase in energy demand caused by industrialization leads to abundant CO2 emissions into atmosphere and induces abrupt rise in earth temperature. It is vital to acquire relatively simple and cost-effective technologies to separate CO2 from the flue gas and reduce its environmental impact. Solid adsorption is now considered an economic and least interfering way to capture CO2, in that it can accomplish the goal of small energy penalty and few modifications to power plants. In this regard, we attempt to review the CO2 adsorption performances of several types of solid adsorbents, including zeolites, clays, activated carbons, alkali metal oxides and carbonates, silica materials, metal–organic frameworks, covalent organic frameworks, and polymerized high internal phase emulsions. These solid adsorbents have been assessed in their CO2 adsorption capacities along with other important parameters including adsorption kinetics, effect of water, recycling stability and regenerability. In particular, the superior properties of adsorbents enhanced by impregnating or grafting amine groups have been discussed for developing applicable candidates for industrial CO2 capture.  相似文献   

5.
CO2 capture using some fly ash-derived carbon materials   总被引:1,自引:0,他引:1  
A. Arenillas 《Fuel》2005,84(17):2204-2210
Adsorption is considered to be one of the more promising technologies for capturing CO2 from flue gases. For post-combustion capture, the success of such an approach is however dependent on the development of an adsorbent that can operate competitively at relatively high temperatures. In this work, low cost carbon materials derived from fly ash, are presented as effective CO2 sorbents through impregnation these with organic bases, for example, polyethylenimine aided by polyethylene glycol. The results show that for samples derived from a fly ash carbon concentrate, the CO2 adsorption capacities were relatively high (up to 4.5 wt%) especially at high temperatures (75 °C), where commercial active carbons relying on physi-sorption have low capacities. The addition of PEG improves the adsorption capacity and reduces the time taken for the sample to reach the equilibrium. No CO2 seems to remain after desorption, suggesting that the process is fully reversible.  相似文献   

6.
Hui An  Bo Feng  Shi Su 《Carbon》2009,47(10):2396-4676
The potential of activated carbon fibre-phenolic resin composites for CO2 capture has been evaluated in this work. A number of composites were fabricated using different types of carbon fibre under various conditions. The effect of a range of variables such as the type of carbon fibre, mass ratio of carbon fibre to phenolic resin, activation temperature and duration on the CO2 adsorption capacity was investigated. Activated carbon derived from powdered phenolic resin demonstrates its capability to capture CO2 and it plays a significant role in the low burn-off range. An apparent optimal degree of activation for CO2 adsorption capacity was identified which was coincident with the maximum micropore volume measured by CO2 physical adsorption. Micropore volume by CO2 has been identified as a potential design parameter for the development of activated carbon fibre-phenolic resin composites for CO2 capture. The existence of a cross-over regime is confirmed and lower burn-off samples are found to capture more CO2 at ambient conditions. This is attributed to a narrow microporosity and a large contribution of micropore volume from smaller pores in the microporosity range of the composites. The optimal pore size for CO2 capture becomes smaller when the relative pressure of CO2 goes lower.  相似文献   

7.
Selective adsorption of CO2 over N2 is important in the design and selection of adsorbents such as metal‐organic frameworks (MOFs) for CO2 capture and sequestration. In this work, single‐component and mixture adsorption isotherms were calculated in MOFs using grand canonical Monte Carlo (GCMC) simulations at conditions relevant for CO2 capture from flue gas. Mixture results predicted from single‐component isotherms plus ideal adsorbed solution theory (IAST) agree well with those calculated from full GCMC mixture simulations. This suggests that IAST can be used for preliminary screening of MOFs for CO2 capture as an alternative to more time‐consuming mixture simulations or experiments. © 2011 Canadian Society for Chemical Engineering  相似文献   

8.
A precise understanding of phase behavior for a variety of both artificial and natural processes is essential to achieving scientific and technological goals. There has been growing research interest in gas hydrates confined in nanoporous media aiming to simulate and analyze the unique behavior of natural gas hydrates in sediments. Moreover, the appearance of peculiar properties due to the confinement effect stimulates research on gas hydrate technology for gas separation, such as CO2 capture from versatile pre/post combustion emissions. In spite of their importance, reliable phase equilibrium data on gas hydrates confined at a nanoscale are scattered throughout the literature, while those in bulk state are abundant. Accordingly, we surveyed the previous studies on the phase behavior of gas hydrates in various nanoporous materials to include and provide valuable information and knowledge for start-up researchers in various gas hydrate fields.  相似文献   

9.
We report on the gas storage behaviour and electrochemical charge storage properties of high surface area activated nanoporous carbon obtained from rice husk through low temperature chemical activation approach. Rice husk derived porous carbon (RHDPC) exhibits varying porous characteristics upon activation at different temperatures and we observed high gas uptake and efficient energy storage properties for nanoporous carbon materials activated even at a moderate activation temperature of 500 °C. Various experimental techniques including Fourier transform-infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy and pore size analyser are employed to characterise the samples. Detailed studies on gas adsorption behaviour of CO2, H2 and CH4 on RHDPCs have been performed at different temperatures using a volumetric gas analyser. High adsorption capacities of ~9.4 mmol g?1 (298 K, 20 bar), 1.8 wt% (77 K, 10 bar) and ~5 mmol g?1 (298 K, 40 bar) were obtained respectively for CO2, H2 and CH4, superior to many other carbon based physical adsorbents reported so far. In addition, these nanoporous carbon materials exhibit good electrochemical performance as supercapacitor electrodes and a maximum specific capacitance of 112 F g?1 has been obtained using aqueous 1 M Na2SO4 as electrolyte. Our studies thus demonstrate that nanoporous carbon with high porosity and surface area, obtained through an efficient approach, can act as effective materials for gas storage and electrochemical energy storage applications.  相似文献   

10.
Atomically detailed models of gas mixture diffusion through CuBTC membranes   总被引:1,自引:0,他引:1  
Metal–organic frameworks are intriguing crystalline nanoporous materials that have potential applications in adsorption-based and membrane-based gas separations. We describe atomically detailed simulations of gas adsorption and diffusion in CuBTC that have been used to predict the performance of CuBTC membranes for separation of H2/CH4, CO2/CH4 and CO2/H2 mixtures. CuBTC membranes are predicted to have higher selectivities for all three mixtures than MOF-5 membranes, the only other metal–organic framework material for which detailed predictions of membrane selectivities have been made. Our results give insight into the physical properties that will be desirable in tuning the pore structure of MOFs for specific membrane-based separations.  相似文献   

11.
A series of high performance carbonaceous mesoporous materials: activated carbon beads (ACBs), have been prepared in this work. Among the samples, ACB‐5 possesses the BET specific surface area of 3537 m2 g?1 and ACB‐2 has the pore volume of 3.18 cm3 g?1. Experimental measurements were carried out on the intelligent gravimetric analyzer (IGA‐003, Hiden). Carbon dioxide adsorption capacity of 909 mg g?1 has been achieved in ACB‐5 at 298 K and 18 bar, which is superior to the existing carbonaceous porous materials and comparable to metal‐organic framework (MOF)‐177 (1232 mg g?1, at 298 K and 20 bar) and covalent‐organic framework (COF)‐102 (1050 mg g?1 at 298 K and 20 bar) reported in the literature. Moreover, methane uptake reaches 15.23 wt % in ACB‐5 at 298 K and 18 bar, which is better than MOF‐5. To predict the performances of the samples ACB‐2 and ACB‐5 at high pressures, modeling of the samples and grand canonical Monte Carlo simulation have been conducted, as is presented in our previous work. The adsorption isotherms of CO2/N2 and CO2/CH4 in our samples ACB‐2 and 5 have been measured at 298 and 348 K and different compositions, corresponding to the pre‐ and postcombustion conditions for CO2 capture. The Dual‐Site Langmuir‐Freundlich (DSLF) model‐based ideal‐adsorbed solution theory (IAST) was also used to solve the selectivity of CO2 over N2 and CH4. The selectivities of ACBs for CO2/CH4 are in the range of 2–2.5, while they remain in the range of 6.0–8.0 for CO2/N2 at T = 298 K. In summary, this work presents a new type of adsorbent‐ACBs, which are not only good candidates for CO2 and CH4 storage but also for the capture of carbon dioxide in pre‐ and postcombustion processes. © 2011 American Institute of Chemical Engineers AIChE J, 2011  相似文献   

12.
The techno-economic evaluation of four novel integrated gasification combined cycle (IGCC) power plants fuelled with low rank lignite coal with CO2 capture facility has been investigated using ECLIPSE process simulator. The performance of the proposed plants was compared with two conventional IGCC plants with and without CO2 capture. The proposed plants include an advanced CO2 capturing process based on the Absorption Enhanced Reforming (AER) reaction and the regeneration of sorbent materials avoiding the need for sulphur removal component, shift reactor and/or a high temperature gas cleaning process. The results show that the proposed CO2 capture plants efficiencies were 18.5–21% higher than the conventional IGCC CO2 capture plant. For the proposed plants, the CO2 capture efficiencies were found to be within 95.8–97%. The CO2 capture efficiency for the conventional IGCC plant was 87.7%. The specific investment costs for the proposed plants were between 1207 and 1479 €/kWe and 1620 €/kWe and 1134 €/kWe for the conventional plants with and without CO2 capture respectively. Overall the proposed IGCC plants are cleaner, more efficient and produce electricity at cheaper price than the conventional IGCC process.  相似文献   

13.
We present a multi-scale framework for the optimal design of CO2 capture, utilization, and sequestration (CCUS) supply chain network to minimize the cost while reducing stationary CO2 emissions in the United States. We also design a novel CO2 capture and utilization (CCU) network for economic benefit through utilizing CO2 for enhanced oil recovery. Both the designs of CCUS and CCU supply chain networks are multi-scale problems which require decision making at material, process and supply chain levels. We present a hierarchical and multi-scale framework to design CCUS and CCU supply chain networks with minimum investment, operating and material costs. While doing so, we take into consideration the selection of source plants, capture processes, capture materials, CO2 pipelines, locations of utilization and sequestration sites, and amounts of CO2 storage. Each CO2 capture process is optimized, and the best materials are screened from large pool of candidate materials. Our optimized CCUS supply chain network can reduce 50% of the total stationary CO2 emission in the U.S. at a cost of $35.63 per ton of CO2 captured and managed. The optimum CCU supply chain network can capture and utilize CO2 to make a total profit of more than 555 million dollars per year ($9.23 per ton). We have also shown that more than 3% of the total stationary CO2 emissions in the United States can be eliminated through CCU networks at zero net cost. These results highlight both the environmental and economic benefits which can be gained through CCUS and CCU networks. We have designed the CCUS and CCU networks through (i) selecting novel materials and optimized process configurations for CO2 capture, (ii) simultaneous selection of materials and capture technologies, (iii) CO2 capture from diverse emission sources, and (iv) CO2 utilization for enhanced oil recovery. While we demonstrate the CCUS and CCU networks to reduce stationary CO2 emissions and generate profits in the United States, the proposed framework can be applied to other countries and regions as well.  相似文献   

14.
The reactions of CO2 with oxirane to produce cyclic carbonate, and with aziridine to afford oxazolidine have been of interest as a useful method for its fixation by a chemical process. Highly efficient processes employing recyclable CO2-phlilic homogeneous catalyst were devised for environmentally benign synthesis of cyclic carbonates and oxazolidinones under supercritical CO2 without any organic solvent. These processes represent pathways for greener chemical fixations of CO2 to afford industrial useful materials such as organic carbonates and oxazolidinones with great potential applications.  相似文献   

15.
CO2 capture by solid sorbents is a physisorption process in which the gas molecules are adsorbed in a different porosity range, depending on the temperature and pressure of the capture conditions. Accordingly, CO2 capture capacities can be enhanced if the sorbent has a proper porosity development and a suitable pore size distribution. Thus, the main objective of this work is to maximize the CO2 capture capacity at ambient temperature, elucidating which is the most suitable porosity that the adsorbent has to have as a function of the emission source conditions. In order to do so, different activated carbons have been selected and their CO2 capture capacities have been measured. The obtained results show that for low CO2 pressures (e.g., conditions similar to post-combustion processes) the sorbent should have the maximum possible volume of micropores smaller than 0.7 nm. However, the sorbent requires the maximum possible total micropore volume when the capture is performed at high pressures (e.g., conditions similar to oxy-combustion or pre-combustion processes). Finally, this study also analyzes the important influence that the sorbent density has on the CO2 capture capacity, since the adsorbent will be confined in a bed with a restricted volume.  相似文献   

16.
Adsorption in porous materials is a promising technology for CO2 capture and storage. Particularly important applications are adsorption separation of streams associated with the coal power plant operation, as well as natural gas sweetening. High surface area activated carbons are a promising family of materials for these applications, especially in the high pressure regimes. As the streams under consideration are generally multi-component mixtures, development and optimization of adsorption processes for their separation would substantially benefit from predictive simulation models. Here, we develop a molecular model of a high surface area carbon material based on a random packing of small fragments of a carbon sheet. In the construction of the model, we introduce a number of constraints, such as the value of the accessible surface area, concentration of the surface groups, and pore volume to bring the properties the model structure close to the reference porous material (Maxsorb carbon with the surface area in excess of 3000 m2/g). We use experimental data for CO2 and methane adsorption to tune and validate the model. We demonstrate the accuracy and robustness of the model by predicting single component adsorption of CO2, methane and other relevant components under a range of conditions.  相似文献   

17.
C.F. Martín 《Fuel》2011,90(5):2064-556
Different types of phenolic resins were used as precursor materials to prepare adsorbents for the separation of CO2 in pre-combustion processes. In order to obtain highly microporous carbons with suitable characteristics for the separation of CO2 and H2 under high pressure conditions, phenol-formaldehyde resins were synthesised under different conditions. Resol resins were obtained by using an alkaline environment while Novolac resins were synthesised in the presence of acid catalysts. In addition, two organic additives, ethylene glycol (E) and polyethylene glycol (PE) were included in the synthesis. The phenolic resins thus prepared were carbonised at different temperatures and then physically activated with CO2. The carbons produced were characterised in terms of texture, chemical composition and surface chemistry. Maximum CO2 adsorption capacities at atmospheric pressure were determined in a thermogravimetric analyser. Values of up to 10.8 wt.% were achieved. The high-pressure adsorption of CO2 at room temperature was determined in a high-pressure magnetic suspension balance. The carbons tested showed enhanced CO2 uptakes at high pressures (up to 44.7 wt.% at 25 bar). In addition, it was confirmed that capture capacities depend highly on the microporosity of the samples, the narrow micropores (pore widths of less than 0.7 nm) being the most active in CO2 adsorption at atmospheric pressure. The results presented in this work suggest that phenol-formaldehyde resin-derived activated carbons, particularly those prepared with the addition of ethylene glycol, show great potential as adsorbents for pre-combustion CO2 capture.  相似文献   

18.
H2 adsorption and syngas purification in charged soc metal-organic framework are investigated using atomistic simulations. As experimentally observed, the extraframework NO3 ions are entrapped in carcerand-like capsule with negligible mobility. At low pressure, H2 adsorption occurs concurrently at multiple sites near the exposed indium atoms and organic components. The capsule is accessible at high pressure through the surrounding channels by restricted windows. Adsorption sites identified are remarkably consistent with inelastic neutron scattering measurements. The isotherm and isosteric heat of H2 adsorption predicted match well with experimental data. As loading rises, the isosteric heat remains nearly constant, revealing the homogeneity of adsorption sites. CO2/H2 selectivity in syngas adsorption is up to 600 and substantially higher than other nanoporous materials. With a trace of H2O, the selectivity increases slightly at low pressure due to promoted adsorption of CO2 by H2O bound proximally to the exposed indium atoms, but decreases at high pressure as a consequence of competitive adsorption of H2O over CO2. © 2009 American Institute of Chemical Engineers AIChE J, 2009  相似文献   

19.
Sharon Sjostrom  Holly Krutka 《Fuel》2010,89(6):1298-27
Processes based upon solid sorbents are currently under consideration for post-combustion CO2 capture. Twenty-four different sorbent materials were examined on a laboratory scale in a cyclic temperature swing adsorption/regeneration CO2 capture process in simulated coal combustion flue gas. Ten of these materials exhibited significantly lower theoretical regeneration energies compared to the benchmark aqueous monoethanolamine, supporting the hypothesis that CO2 capture processes based upon solids may provide cost benefits over solvent-based processes. The best performing materials were tested on actual coal-fired flue gas. The supported amines exhibited the highest working CO2 capacities, although they can become poisoned by the presence of SO2. The carbon-based materials showed excellent stability but were generally categorized as having low CO2 capacities. The zeolites worked well under dry conditions, but were quickly poisoned by the presence of moisture. Although no one type of material is without concerns, several of the materials tested have theoretical regeneration energies significantly lower than that of the industry benchmark, warranting further development research.  相似文献   

20.
The enormous emission of carbon dioxide (CO2) from industries has triggered a series of environmental issues. In recent years, ionic liquids (ILs) as novel absorbents are widely used for CO2 capture owing to their low vapor pressure and tunable structures. IL-modified adsorbents have the advantages of both ILs and porous supports, such as high CO2 selectivity and high specific surface area, which are novel agents to capture CO2 with broad application prospects. In this review, more than 140 IL-modified adsorbents for CO2 capture in recent years were systematically summarized. The types of ILs including conventional ILs and functionalized ILs on CO2 separation performance of different IL hybrid adsorbents, and their adsorption mechanisms were also discussed. Finally, future perspectives on IL-modified adsorbents for CO2 separation were further posed.  相似文献   

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