Co2+ separation from

Figure 48 (a) H-bonded assembly of the carbamate 41. (b) Interlinking H-bonds with contiguous cell units, (c) Side view of the assembly, (d) Pleated-sheet staircase-like H-bonded core with bifurcated H-bonds. (e) Single strand of diamine 29 and CO2 separated from the triple-stranded helicate for viewing purposes. Note right-handed helicity [51]. 

Meldon JH and Dutta A. Analysis of ultimate permselectivity for H2S over CO2 in alkaline solutions. Chem Eng Sci, 1994 49(5) 689-697. Saha S and Chakma A. Selective CO2 separation from CO2/C2H6 mixtures by immobilized diethanolamine/PEG membranes. J Mem... 

Chen H, Ohuskovic G, Majumdar S, and Sirkar KK. Immobilized glycerol-based liquid membranes in hollow fibers for selective CO2 separation from CO2-N2 mixtures. J. Mem. Sci. 2001 183 75-88. 

Saha S, Chakma A. Selective CO2 separation from CO2/C2H, mixtures by immobilized diethanolamine/PEG membranes. J Membr Sci 1995 98 157-171. 

SILMs have been also employed for the separation of CO2/N2 and CO/ CH4 mixtures. Scovazzo et al. [54] used common ionic liquids such as imidazohum [emim] + and different water stable anions such as bis(trifluor-omethanesulfonyl)amide [T N] , trifluoromethanesulfone [CFsSOj] , and dicianamide dca in polyethersulfone as polymer substrate. It was observed an interesting increase in CO2 permeability (up to 50%) decreasing the gas phase pressure from 19 to 1.5 kPa with an ideal selectivity (CO2/N2) ranging from 15 (for CI ) up to 61 (for [dca] ) and permeabilities of 350 barrer (for CI ) to 1000 barrer (for [T N] ). In the case of CO2 separation from CH4, the ideal selectivity was ranging from 4 (for [Cl ) to 20 (for dca ) which are above the upper-bound for the CO2/CH4 Robson plot. 

H. Chen, A. S. Ko wall, S. Majumdar, K. K. Sirkar, Selective CO2 separation from CO2-N2 mixtures by immobilised carbonate-glycerol membranes, Ind. Eng. Chem. Res. 38 (1999) 3489-3498. 

New apphcations can be expected in the area of dendrimer-immobilized liquid niembranes. By using polyvmyhdene fluoride membrane films containing a generation zero PAMAM dendrimer, highly selective CO2 separation from gas mixtures is possible [26]. Dendrimers consisting of a cationic core shell and an apolar... 

The selection of the liquid absorbents in membrane contactors is critical. The commonly used absorbents for CO2 removal are amine based (i.e., MEA, DEA, and TEA) [160-163], Recently, membrane contactors using ILs as alternative absorbents for the capture of acid gases have been reported [166-170], The unique properties of ILs (nonvolatile with a high affinity for the acid gas component, thermally and chemically stable [171]) make it very promising as CO2 absorbents in membrane contactors, especially for applications in harsh conditions, such as CO2 separation from precombustion flue gas at elevated temperatures and pressures [169,170]. 

Cheung, O., Hedin, N. Zeolites and related sorbents with narrow pores for CO2 separation from flue gas. RSC Adv. 4, 14480-14494 (2014)... 

Zeolite membranes with different topology were studied for CO2 separation from light gases. Table 17.5 reports some of the different results present in the open literature about CO2/N2 and CO2/CH4 separations. 

Table 19.4 Comparison of the three systems utilized in CO2 separation from flue gas streams as a function of feed and product conditions...

The world s first industrial-scale CO2 storage was at Norway s Sleipner gas field in the North Sea, where about one million tons per year of compressed liquid CO2 separated from methane is injected into a deep reservoir (saline aquifer) about a kilometer below the sea bed and remains safely in place. The natural gas contains 9% CO2 which must be reduced before sale or export. The overall Utsira sandstone formation there, about 1 km below the sea bed, is said to be capable of storing 600 billion tons of CO2. 

The application of ILs as carbon precursors is an attractive field within the research area of carbon chemistry. Nitrile-containing task-specific ILs and DESs are a promising class of monomers for the synthesis of carbonaceous materials. The architecture of TSlLs allows for a wide combination of nitrile-modified cations and anions, tailoring the properties of the resulting porous solids. The attractive properties of IL-derived nitrogen-doped carbons make them a promising material for potential application in CO2 separation from flue gas. 

Fig. 2.16 CO2 adsorption evaluation of the PCNs. a, b CO2 adsorption isotherms for high and low CO2 partial pressures at 25 °C, where the solid line represents a Toth model fit to the CO2 isotherms, c The number of CO2 molecules adsorbed per nm pore volume and d per nm surface area for PCNs with different thickness, e, f CO2 separation evaluation of PCN-17 in dynamic breakthrough tests, e Breakthrough curves and f cycling of CO2 separation from a stream of CO2/H2O/ N2 of 4/3/93 v% at 25 °C, following a regeneration by an Ar purge at 50 °C. Reproduced from Ref. [71] by permission of The Royal Society of Chemistry...

CO2 capture from coal and natural gas fired power plants is important if the atmospheric CO2 levels are to be kept within accepted limits. Currently utilized commercial technology for CO2 separation from natural or synthesis gas is amine solvent-based absorption. But this process has its own drawbacks such as amine loss, handling of corrosive liquids, and removal of SO2 when applied to post-combustion CO2 capture [3]. Plus amine absorption process is not fiscally viable as the cost associated with it is around 80 % of the total CO2 sequestration cost [4]. Thus, efforts are being made to develop materials and methods that can significantly reduce the capture and storage costs along with efficient performance. 

CO2 separation from flue gases (post-combustion removal). 

CO2 separation from fuel processing including CO conversion of synthesis gas, carbon separation from high-hydrogen content fuels (pre-combustion removal). 

CO2 separation from concentrated exhaust gases (e.g. oxy-fuel combustion). 

Figure 10.3 compares the uptakes of CO2, CH4, N2, H2 and Ar adsorbed on JUC-Z4 at 273 K. JUC-Z4 exhibits high adsorption selectivity for CO2 over N2 specifically at low pressure, while at higher pressure selectivity decreases. This selectivity is predicted to be higher than several porous networks like MOFs. CO2 separation from H2 by JUC-Z4 is also found to be pretty good at ambient pressure and temperature. Such exceptional separation performance makes JUC-Z4 a potential candidate as a selective separator and absorber for CO2 capture. ... 

Xiao S, Chun G, Zhao Y, Chen HJ Effect of temperature fluctuation on hydrate-based CO2 separation from fuel gas, J Nat Gas Chem 20(6) 647-653, 2011. 

CO2 separation from the anode loop is another challenge in liqttid-fed DMFC operation. Fuel and water losses are to be expected from the CO2 separator and have to be dealt with by the system. 

Kowali AS, Sirkar KK (2001) Dendrimer liquid membranes CO2 separation from gas mixtures. Ind Eng Chem Res 40 2502-2511... 

Sustained efforts to reduce CO2 emissions because of the potential of CO2 separation from pressurized syngas (e.g., the United States)... 

Separation of CO2 from hydrocarbons CO2 separated from light hydrocarbons in natural gas streams at high pressures CO2 separated from biogas (containing CO2 and methane) CO2 separated from breathing gas mixture. 

In order to further investigate the efficiency of the incorporated SMTs for CO2 uptake, control experiments were accomplished by deliberate obstruction of the SMTs in PCN-88 (Figure 9d). Consequently, PCN-88 was synthesized by one-pot reaction of the ligand and copper salt in the presence of pyrazine, and it has an identical structure with that of PCN-88 except that the SMTs were blocked by the pyrazine molecules. A significant difference of CO2 uptake between PCN-88 and PCN-88 at lower pressures (especially <0.2 atm) was observed, which should probably be attributed to the existence of SMTs in the PCN-88 framework. This is particularly valuable for CO2 separation from flue gas, where the partial pressure of CO2 is about 0.15 atm. ... 

Presentation of Techniques for CO2 Separation from Gaseous Effluents... 

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