According to the characteristics of power plant flue gas emission and the requirements of reducing CO
2
capture cost. CO
2
absorption hybrid with microalgae conversion (CAMC) can avoid the challenges ...of heat consumption during absorbent desorption and nutrient consumption during microalgae culture. In this study, the bicarbonate solution (represents the products of CO
2
absorption by Na
2
CO
3
and K
2
CO
3
) is used as carbon source for mutagenic
Spirulina platensis
cultivation, and different concentrations of bicarbonate were set to explore the best carbon source. The results showed that NaHCO
3
was a better medium for the CO
2
absorption hybrid with microalgae conversion system, which was beneficial for the growth of mutagenic
Spirulina
, compared with K
2
CO
3
. When .3 mol/L NaHCO
3
was added to the CO
2
absorption hybrid with microalgae conversion system, the highest biomass dry weight, carbon fixation rate and carbon utilization efficiency were obtained, which were 2.24 g/L, 230.36 mg/L/d and 26.71%, respectively. In addition, .3 mol/L NaHCO
3
was conducive to protein synthesis, reaching 1,625.68 mg/L. This study provided a feasible idea for power system to achieve carbon neutrality in the future.
The global warming effect caused by CO2 emissions has a significant impact on human activities. Membrane technology has been regarded as a potential promising separation technology due to its low ...energy-consumption and low carbon footprint. In recent decades, numerous researches on CO2 selective membranes have been reported for carbon capture. The emergence of N2 selective membranes with “reversed N2/CO2 selectivity” property provides a novel perspective for carbon capture process with high efficiency and low energy consumption. However, there is still a gap in the study of N2 selective membranes in hybrid carbon capture process. In present work, a novel hybrid N2 selective membrane-cryogenic process was designed for post-combustion carbon capture. The result indicated that N2 selective membrane-cryogenic hybrid process had an advantage of low membrane area demand and capture cost. The carbon capture cost and energy consumption of the optimization case were $28.17/tCO2 and 1.46 GJ/tCO2, respectively. And it was also found that developing N2 selective membranes with high N2/CO2 selectivity was more promising than that with high N2 permeance in hybrid membrane-cryogenic carbon capture process.
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CO2 released from fossil fuels has made a great contribution to global warming, and natural deep eutectic solvents (NADES) offer an attractive option for greening CO2 capture. Being economical ...natural materials, L-arginine (L-Arg) and glycerol (Gly) were used to synthesize a series of novel hydrophilic NADES (L-Arg/Gly, at mole ratios of 1:4, 1:5, 1:6, 1:7, 1:8). The L-Arg/Gly (1:6) DES showed excellent thermal stability (Tmax, 250 °C; Tf, 13.7 °C). The hydrates of L-Arg/Gly DES (at water contents of 0 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%) were also prepared. The synthesis process of L-Arg/Gly DES and its hydrate were studied with FT-IR and in situ IR spectroscopy. High hydrophilicity of such solvent was demonstrated with fast and efficient capture of CO2 at a high absorption (0.511 mol CO2/mol NADES) under optimized conditions. In the gas-liquid absorption process, the hydrophilic properties of L-Arg/Gly DES and its hydrate greatly reduced the transfer barrier, and accelerated the phase transfer by increasing accessibility of active amine sites on NADES and CO2. And the dynamics for the CO2 absorption was investigated correspondingly. The absorption behaviors of CO2 in L-Arg/Gly DES and its hydrate were studied by in situ IR spectrometer and nuclear magnetic resonance (1H NMR, 13C NMR), and the characteristic infrared peaks and shifts of CO2 absorption were observed. In addition, the L-Arg/Gly DES could be reused for 5 times without obvious inactivation. Indicating the L-Arg/Gly DES would be a potential substitute of the traditional volatile amine solvents for CO2 capture.
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CO2 capture and utilization (CCU) is an effective strategy to mitigate global warming. Absorption, adsorption and membranes are methods used for CO2 separation and capture, and various catalytic ...pathways have also been developed for CO2 utilization. Although widely researched and used in industry, these processes are energy-intensive and this challenge needs to be overcome. To realize further optimization, novel materials and processes are continuously being developed. New generation materials such as ionic liquids (ILs) have shown promising potential for cost-effective CO2 capture and utilization. This study reviews the current status of ILs-based solvents, adsorbents, membranes, catalysts and their hybrid processes for CO2 capture and utilization. The special properties of ILs are integrated into new materials through hybridization, which significantly improves the performance in the process of CCU.
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•Novel DES is developed to tailor the interfacial microenvironment of MMMs.•Filler agglomeration was significantly suppressed after the introduction of DES.•DES provides an additional ...facilitated transport pathway.•Gas separation performance of the MMMs is improved after the addition of DES.
CO2 separation process based on mixed matrix membranes (MMMs) is considered as an effective way to mitigate global warming. However, due to the phase difference between inorganic fillers and polymers of MMMs, it is easy to produce non-ideal structures that are not conducive to gas separation. In this work, a novel deep eutectic solvent (DES) was developed to modulate the microenvironment in MMMs for efficient CO2 separation. Tailored DES as the third component can effectively avoid filler agglomeration after being introduced into the membrane. Compared with the binary system, the CO2 permeability and selectivity of the ternary MMM are improved by 38% and 9%, respectively. And the separation performance of ternary membranes for the mixed gas also exceeds the Robeson upper bound 2008. The performance improvement is not only due to structural optimization, but the result of multi-factor synergy. The tailored DES has excellent CO2 affinity and can provide an additional facilitated transport pathway according to the DFT calculation results.
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•Non-ideal mathematic model for hollow facilitated transport membrane module is established.•Pressure drop, concentration polarization and Joule-Thomson effect have significant ...influence on separation process.•Hollow facilitated transport membrane module with short fiber length, moderate packing fraction and high fiber inner diameter is promising for practical application.
Membrane separation technology has been regarded as a promising alternative for carbon capture process due to its low consumption and low footprint. Facilitated transported membranes exhibit attractive CO2/N2 separation performance due to the existence of CO2-philic reactive carriers. However, the highly pressure and temperature dependent CO2 permeance of it, as well as non-ideal effect, make the simulation of carbon capture process based on simplifying model challenging. Herein, we established a rigorous model for hollow fiber facilitated transport membrane considering both non-ideal effect and variable permeance. This rigorous model was applied for post-combustion carbon capture, and compared with simple model which only considering variable permeance. It was found that rigorous model has a 44%-55% lower carbon capture capacity due to the declined driving force and permeance. Pressure loss accounts for the deviation at low stage cut (10%), while Joule-Thomson effect and concentration polarization effect become greater at high stage cut (20%). Thanks to the mild condition of post combustion flue gas, the impact of real gas behavior can be neglected. Moreover, the attractive configuration of hollow fiber facilitated transport membrane was found to be with relative short fiber length, moderate packing fraction and large fiber inner diameter.
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•MOFs-based MMMs materials for CO2 separation are systematically reviewed;•The non-ideal interface is the key obstruct for fabricating MMMs;•Advanced characterizations of the ...non-ideal interface are summarized;•Interfacial regulation is deconstructed as architecting single or multiple interfaces;•Several prospects for the defect-free MMMs are put forward.
Due to the characteristics of simplicity, efficiency, adaptability and eco-friendly, membrane separation technology has been widely considered to play an important role in CO2 separation. Mixed matrix membranes (MMMs) combined advantages of various components have attracted masses of attention, providing a potential possibility for the large-scale popularization and application of membrane separation technology. Metal organic frameworks (MOFs) are considered as ideal candidates to fabricate defect-free MMMs. However, the further application of MMMs was seriously hindered due to the non-ideal interface between MOFs and polymer matrix. The review focused on the interfacial structure between MOFs and polymer in MMMs for CO2 separation. The interfacial optimization in MMMs was deconstructed into single enhancement of filler-polymer and multiple transitions of filler-extra phase-polymer. The prospects and potential problems of interfacial formation and advanced characterization of MOFs-based MMMs were discussed. Finally, the prospects and challenges for ultrathin and defect-free MMMs fabrication were outlined. This review will offer some inspiration for the fabrication of high-performance MMMs for CO2 separation from the point of view of non-ideal interfacial regulation.
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•The Pebax-based MMMs with hierarchical ZIF-67-L are constructed.•The micro-mesoporous multi-dimensional CO2 expressways and CO2 affinity sites facilitate the CO2 diffusion and ...solubility.•The 2D leaf-shape oriented crystalline “brick-and-mortar” arrangement provide extra CO2 selective corridors.•The functional microarchitecture provides an alternative answer for industrial application of MMMs.
Mixed matrix membranes (MMMs) consisting of poly(ether-block-amide) (Pebax 1657) as the continuous phase and hierarchical leaf-like ZIF-67-L as dispersed microarchitectures for CO2/N2 separation were fabricated. The multidimensional channels and open interaction sites provided stable and rapid CO2 transmission, the intrinsic ZIF-67 crystal characteristics and unique leaf-like morphology-oriented crystalline arrangements provided extra CO2/N2 selectivity contribution, and the “trade-off” effect was successfully overcome. The intramembrane microarchitectures and CO2/N2 separation performance were evaluated by SEM, EDS, XRD, N2 sorption/desorption, FTIR, TGA, DSC and home-made gas permeability measurements. The optimal performance could be observed in ZIF-67-L/Pebax MMMs with 10 wt% loading under pure gas test conditions, compared with the neat Pebax membrane, the CO2 permeability and ideal CO2/N2 selectivity were improved by 74.1% and 23.6%, respectively. As a consequence, the present work provides rational suggestions for constructing selective microarchitecture in MMMs under CO2 capture scenarios and other membrane separation scenarios.
