Carbon Dioxide Sorption Research Articles

In situ monitoring of CO2$$ {}_2 $$ sorption on polyethylenimine dynamics through broadband dielectric spectroscopy

AbstractChemical reactions between carbon dioxide (CO) and amine have been extensively characterized, however, their influence on the dynamics of polyamines remains largely unexplored. In this work, we compare the dynamics of polyethylenimine (PEI) before and after CO absorption through broadband dielectric spectroscopy (BDS). The molecular processes of bulk PEI are very different from those of thin film PEI, highlighting an interesting interface and nano‐confinement effect. Detailed analyses show CO absorption slows down the PEI dynamics, which is consistent with an elevated glass transition temperature of PEI upon CO absorption from differential scanning calorimetry measurements. Further in situ kinetic measurements demonstrate nonmonotonic changes in relaxation times or dielectric amplitudes of some relaxation processes during CO sorption or desorption, suggesting an intriguing interplay between CO chemisorption and the dynamics of PEI. These results demonstrate that BDS is a powerful platform to resolve the temporal dynamics changes of polyamines for CO capture.

The influence of HKUST-1 and MOF-76 hand grinding/mechanical activation on stability, particle size, textural properties and carbon dioxide sorption

In this study, we explore the mechanical treatment of two metal–organic frameworks (MOFs), HKUST-1 and MOF-76, applying various milling methods to assess their impact on stability, porosity, and CO2 adsorption capacity. The effects of different mechanical grinding techniques, such as high-energy ball milling and hand grinding, on these MOFs were compared. The impact of milling time, milling speed and ball size during high-energy ball milling was assessed via the Design of Experiments methodology, namely using a 33 Taguchi orthogonal array. The results highlight a marked improvement in CO2 adsorption capacity for HKUST-1 through hand milling, increasing from an initial 25.70 wt.% (5.84 mmol g-1) to 41.37 wt.% (9.40 mmol g-1), marking a significant 38% increase. In contrast, high-energy ball milling seems to worsen this property, diminishing the CO2 adsorption abilities of the materials. Notably, MOF-76 shows resistance to hand grinding, closely resembling the original sample’s performance. Hand grinding also proved to be well reproducible. These findings clarify the complex effects of mechanical milling on MOF materials, emphasising the necessity of choosing the proper processing techniques to enhance their stability, texture, and performance in CO2 capture and storage applications.

Nickel augmented biochar for sustaining produced water treatment to decarbonize oil and gas industrial waste using anaerobic-aerobic granular cylindrical periodic discontinuous batch reactors

This study assessed the efficacy of granular cylindrical periodic discontinuous batch reactors (GC-PDBRs) for produced water (PW) treatment by employing eggshell and waste activated sludge (WAS) derived Nickel (Ni) augmented biochar. The synthesized biochar was magnetized to further enhance its contribution towards achieving carbon neutrality due to carbon negative nature, Carbon dioxide (CO2) sorption, and negative priming effects. The GC-PDBR1 and GC-PDBR2 process variables were optimized by the application of central composite design (CCD). This is to maximize the decarbonization rate. Results showed that the systems could reduce total phosphorus (TP) and chemical oxygen demand (COD) by 76–80% and 92–99%, respectively. Optimal organic matter and nutrient removals were achieved at 80% volumetric exchange ratio (VER), 5 min settling time and 3000 mg/L mixed liquor suspended solids (MLSS) concentration with desirability values of 0.811 and 0.954 for GC-PDBR1 and GC-PDBR2, respectively. Employing four distinct models, the biokinetic coefficients of the GC-PDBRs treating PW were calculated. The findings indicated that First order (0.0758–0.5365) and Monod models (0.8652–0.9925) have relatively low R2 values. However, the Grau Second-order model and Modified Stover-Kincannon model have high R2 values. This shows that, the Grau Second Order and Modified Stover-Kincannon models under various VER, settling time, and MLSS circumstances, are more suited to explain the removal of pollutants in the GC-PDBRs. Microbiological evaluation demonstrated that a high VER caused notable rises in the quantity of several microorganisms. Under high biological selective pressure, GC-PDBR2 demonstrated a greater percentage of nitrogen removal via autotrophic denitrification and a greater number of nitrifying bacteria. The overgrowth of bacteria such as Actinobacteriota spp. Bacteroidota spp, Gammaproteobacteria, Desulfuromonas Mesotoga in the phylum, class, and genus, has positively impacted on granule formation and stability. Taken together, our study through the introduction of intermittent aeration GC-PDBR systems with added magnetized waste derived biochar, is an innovative approach for simultaneous aerobic sludge granulation and PW treatment, thereby providing valuable contributions in the journey toward achieving decarbonization, carbon neutrality and sustainable development goals (SDGs).

Biochar Enriched Concrete for Carbon Sequestration

Abstract: In upcoming years , a lot of construction is going to happen leading to more cement consumption and more GHG’s emissions by default as an embodied carbon. Reduction of cement consumption is possible by partially repacing it with biochar which is a by-product of pyrolysis of biomass or adding it as an additive in cement mortar and concrete for carbon sequestration. Biochar is effective in carbon sequestration activity and results in high water and carbon dioxide holding capacity. Increase in biochar lead to increase in carbon sequestration . As pozzolanic activity lead to strength gaining characteristics and durability of concrete, this study focusses on investigating pozzolanic activity of biochar. Biomass considered in this study were walnut shells and pretreatment was done with 0.1 N HCl and and pozzolanic activity is checked by chapelle test by observing Ca(OH)2 fixation during the titration. It was observed that increase in temperature or Normality of HCl in pretreatment does not enhance pozzolanic activity of biochar . Hence pretreatment with 0.1 N HCl at room temperature for an hour is sufficient to enhance the pozzolanic activity of biochar with much high carbon dioxide sorption as compared to usual concrete without compromising with the strength of concrete. This study reclaims the potential use of biochar in concrete is reliable for carbon sequestration.

Preparation and Testing of Polyethylenimine-Impregnated Silica Gel for CO2 Capture.

This work studied the low-temperature sorption of carbon dioxide on impregnated silica gel. An impregnating agent was used polyethyleneimine. The content of the impregnating agent in the silica gel matrix was 33.4 wt.%. Material properties such as the Brunauer-Emmett-Teller (BET) surface area, pore distribution, total pore volume, and thermal stability of the impregnated material were determined for the sample. During the measurement of the adsorption-desorption cycles, the loss of the impregnating agent in the material matrix was also determined. Due to the decrease in the content of polyethyleneimine, the sorption capacity of the adsorbent for CO2 also decreased. It was found that after the 20th adsorption-desorption cycle, the content of the impregnating agent in the adsorbent dropped by 3.15 wt.%, and, as a result, the adsorption capacity for CO2 dropped to almost half.

On the Low-Pressure Hysteresis (LPH) in Gas Sorption Isotherms of Porous Carbons.

This study investigates the origin of low-pressure hysteresis (LPH) in the adsorption and desorption of three different probe molecules: carbon dioxide, nitrogen, and argon, across various adsorption temperatures (from cryogenic to room temperature), and within five different carbon materials: synthetic carbons (pristine and one post-synthetically oxidized) and natural coal. Significant attention is dedicated to elucidating LPH in oxidized samples outgassed at various temperatures (120-350°C). Experimental results show that insufficient outgassing temperature can lead to unreliable data due to artificial LPH and significantly underestimated textural properties, primarily caused by porosity blockage from substances like moisture. Conversely, in samples where heteroatoms have a stabilizing effect on texture, such as natural coal, careful consideration of outgassing temperature is crucial due to the risk of thermal degradation. Other factors contributing to LPH are adsorption temperature, and especially, kinetic limitations at cryogenic temperatures for cellulose-based carbons. Minor factors responsible for LPH are the physical state of the sample (monolith vs powder) and the flexibility of the porous system, both studied by carbon dioxide sorption. This study constitutes an important piece in the evaluation of LPH, providing practical recommendations and underlining the importance of experimental design, with implications for further research in this complex field.

Investigation on desulfurization and ground granulated blast furnace slags reutilization for carbon dioxide sorption in a fluidized bed reactor

BackgroundThe atmospheric CO2 concentration is significantly increasing due to the utilization of fossil fuel in various activities. Implementation of steel slag is considered as a promising strategy for carbon capture MethodsIn this study, the slags from desulfurization (De-S) and ground granulated blast furnace (GGBS) processes in the steel company waste were applied as the sorbent in CO2 removal using a fluidized bed system. Various operating conditions were applied to determine the influence of operating parameters on sorbent performance. Moreover, examination on sorbent characteristic change and kinetics calculation were also carried out in this study. Significant findingOptimum operating temperature was reached by the application of 600 and 500 °C for De-S and GGBS slag, respectively. The higher CO2 concentration and 5 % water vapor improved the sorbent utilization. However, excessive water vapor and low fluidized velocity decreased the performance of sorbent. De-S slag performed better on overall CO2 capture process compared to GGBS slag. Therefore, upscaled study with 10 times greater size was further conducted with the 150–300 µm De-S slag for the CO2 capture from oxy-fuel and air combustion. The higher CO2 partial pressure in the flue gas of oxy-fuel combustion increased the capture process efficiency.

Thermochemical battery prototypes with conductive heat extraction

Thermochemical energy storage is a viable option for large-scale storage of renewable energy. Functional storage systems require a high cycling capacity and an efficient heat extraction unit to guarantee reliable energy storage and subsequent power production. This article investigates the performance of thermochemical battery prototypes that use conductive heat extraction via metallic rods. The thermodynamics and kinetics of the storage material, CaCO3-Al2O3 (20 wt%), used in the prototypes, were studied along with the cyclic carbon dioxide sorption capacity, which was retained at 60 %. The reaction thermodynamics and kinetics of this doped CaCO3 compound are similar to those reported for pure calcium carbonate (ΔHdes = 173 ± 10 kJ.mol−1 CO2 and ΔSdes = 147 ± 9 J.mol−1 CO2·K−1). The two prototypes were constructed using either a stainless-steel rod or a stainless-steel tube with a copper core as conductive heat exchanger. The thermochemical battery prototypes (∼1 kg) cycled >30 times, with thermal charging (calcination) and discharging (carbonation) at ∼900 °C. The storage material is sensitive to the operating conditions of pressure and temperature, which influence the formation of various calcium aluminium oxide compounds that either catalyse or inhibit the cyclic capacity. The carbon dioxide sorption capacity in the prototypes was found to be limited (20 %) and capacity loss was correlated to the temperature distribution through the storage material and limited by the heat transfer rate of the heat extraction system. The heat transfer performance of the stainless-steel rod was inadequate, while the copper core allowed for better system performance.

Sorption of Soil Carbon Dioxide by Biochar and Engineered Porous Carbons.

CO2 is 45 to 50 times more concentrated in soil than in air, resulting in global diffusive fluxes that outpace fossil fuel combustion by an order of magnitude. Despite the scale of soil CO2 emissions, soil-based climate change mitigation strategies are underdeveloped. Existing approaches, such as enhanced weathering and sustainable land management, show promise but continue to face deployment barriers. We introduce an alternative approach: the use of solid adsorbents to directly capture CO2 in soils. Biomass-derived adsorbents could exploit favorable soil CO2 adsorption thermodynamics while also sequestering solid carbon. Despite this potential, previous study of porous carbon CO2 adsorption is mostly limited to single-component measurements and conditions irrelevant to soil. Here, we probe sorption under simplified soil conditions (0.2 to 3% CO2 in balance air at ambient temperature and pressure) and provide physical and chemical characterization data to correlate material properties to sorption performance. We show that minimally engineered pyrogenic carbons exhibit CO2 sorption capacities comparable to or greater than those of advanced sorbent materials. Compared to textural features, sorbent carbon bond morphology substantially influences low-pressure CO2 adsorption. Our findings enhance understanding of gas adsorption on porous carbons and inform the development of effective soil-based climate change mitigation approaches.

Dual synergistic effect of the amine-functionalized MIL-101@cellulose sorbents for enhanced CO2 capture at ambient temperature

The development of high carbon dioxide (CO2) sorption capacity materials is necessary for the deployment of the CO2 capture and storage strategy. Metal-organic frameworks (MOFs) have emerged as promising substitutes for traditional liquid and solid CO2 capture sorbents due to their high surface area, tunable pore size, diverse composition, and various physical and chemical properties. However, MOFs feature the intrinsic limitations of powder agglomeration, weak binding affinity, and sluggish diffusion kinetics, thus hindering their industrial application in CO2 capture. Herein, we design an amine-functionalized MIL-101@cellulose (NH2-MIL-101@BM) composite sorbent by anchoring NH2-MIL-101 nanoparticles onto the BM matrix through hydrogen bonding interaction. The dual synergistic effect, origin from the physical sorption synergistic effect and chemisorption synergistic effect proposed between NH2-MIL-101 and BM, not only facilitates the mass transfer of CO2 by reducing the diffusion resistance through hierarchical-pore structure but also offers stronger sorption sites with CO2 by increasing the adsorption energy of metal-CO2 or amine-CO2, which are confirmed by series of characterizations and theory functional calculations. Benefiting from the above merits, the NH2-MIL-101@20 %BM sorbent delivers a superior initial CO2 sorption capacity of 13.4 mmol/g when the BM doping amount is 20 wt% at 25 °C, and also shows good recycle stability even after 15 runs with maintainable structure. This work displays the in-depth mechanism understanding for enhanced CO2 capture, providing value inspiration for future MOF-based composite sorbent construction for CO2 capture at ambient temperatures.

Reversible sorption of carbon dioxide in Ca–Mg–Fe systems for thermochemical energy storage applications

CO2 sorption in Ca–Mg–Fe materials developed for thermochemical batteries with enhanced reversibility by the formation of dicalcium and magnesium ferrites.

A detailed molecular dynamics simulation and experimental investigation of CO2 adsorption on graphene oxide-polyaniline nanocomposite

The study investigated the sorption and diffusion of carbon dioxide on Graphene oxide-polyaniline (GO-PANI) using volumetric method and molecular dynamics simulations. The experimental results showed that GO-PANI was more effective at adsorbing CO2 than either of the individual materials alone. Simulations supported this trend in CO2 adsorption and provided additional insights into the structural information of the adsorbents and the dynamics of CO2 molecules. The Langmuir adsorption model was employed to fit sorption isotherms computed using Grand Canonical Monte Carlo (GCMC) method. The GO-PANI nanocomposite compound exhibited a superior adsorption rate compared to pure structures. The isosteric heat for CO2 adsorption was 27.59 kJ/mol. The interaction energy of single molecules of CO2 on GO-PANI surface was −38.075 kcal/mol. Diffusion coefficient value for CO2 was 41.2 × 10 −9 m2/s, lower than that of the pure polymer. FT-IR, FE-SEM, and BET techniques were used to analyze synthesized GO-PANI structure. The highest CO2 adsorption was observed at a temperature of 283 K. Isosteric heat adsorption decreased with uniform surface charge. This research provides critical microscopic information on gas adsorption in polymer nanocomposites and demonstrates the effectiveness of GO-PANI as an efficient adsorbent for carbon dioxide, which could be useful in various industrial applications.

Modeling of methane and carbon dioxide sorption capacity in tight reservoirs using Machine learning techniques

The viability of enhanced coalbed methane recovery (ECBM) and enhanced shale gas recovery (ESGR) are abundantly explored in various studies since they present a solution for ongoing energy demand and environmental crisis. As a matter of challenge, the prediction of the gas sorption profile poses a significant obstacle in the development of such resources. In this regard, mathematical models, numerical simulations, empirical correlations, and experimental measurements suffer from over-simplification, computationally extensive calculations, time-consuming, and costly processes. This work examines different machine learning methods, from shallow to deep learning, to investigate their capability to model 3804 data points of methane (CH4) and/or carbon dioxide (CO2) sorption capacity in shale and coal at different thermodynamic conditions. Percentage of CO2 in injection gas, rock type, total organic carbon (TOC), moisture, temperature, and pressure were taken as input. Hyperparameter tuning was executed by Optuna optimizer. According to the results, the random forest (RF) was the most proficient predictor for both test subsets of CH4 (MAE = 0.0864, MSE = 0.0231, RMSE = 0.1520) and CO2 (MAE = 0.0529, MSE = 0.0533, RMSE = 0.2308) sorption capacity. Based on the trend prediction simulation, RF predictors were able to properly capture the single and binary sorption capacities. More importantly, they successfully predict the abnormal descending behavior of CO2 sorption in high pressures. In addition, a sensitivity analysis was carried out to acquire the importance of input features and model hyperparameters in the training process. Input feature impacts were consistent with technical expectations of geology and reservoir engineering aspects. Both models are capable of being applied to lab scale and further developed for their application in reservoir scale simulators.

Effect of Water-Soluble Polymers on the Dynamics of Carbon Dioxide Sorption by Lime-Based Sorbents

Effect of Water-Soluble Polymers on the Dynamics of Carbon Dioxide Sorption by Lime-Based Sorbents

A Porous Crystalline Nitrone-Linked Covalent Organic Framework.

Herein, we report the synthesis of a nitrone-linked covalent organic framework, COF-115, by combining N, N', N', N'''-(ethene-1, 1, 2, 2-tetrayltetrakis(benzene-4, 1-diyl))tetrakis(hydroxylamine) and terephthaladehyde via a polycondensation reaction. The formation of the nitrone functionality was confirmed by solid-state 13 C multi cross-polarization magic angle spinning NMR spectroscopy of the 13 C-isotope-labeled COF-115 and Fourier-transform infrared spectroscopy. The permanent porosity of COF-115 was evaluated through low-pressure N2 , CO2 , and H2 sorption experiments. Water vapor and carbon dioxide sorption analysis of COF-115 and the isoreticular imine-linked COF indicated a superior potential of N-oxide-based porous materials for atmospheric water harvesting and CO2 capture applications. Density functional theory calculations provided valuable insights into the difference between the adsorption properties of these COFs. Lastly, photoinduced rearrangement of COF-115 to the associated amide-linked material was successfully demonstrated.

A Porous Crystalline Nitrone‐Linked Covalent Organic Framework**

AbstractHerein, we report the synthesis of a nitrone‐linked covalent organic framework, COF‐115, by combining N, N′, N′, N′′′‐(ethene‐1, 1, 2, 2‐tetrayltetrakis(benzene‐4, 1‐diyl))tetrakis(hydroxylamine) and terephthaladehyde via a polycondensation reaction. The formation of the nitrone functionality was confirmed by solid‐state 13C multi cross‐polarization magic angle spinning NMR spectroscopy of the 13C‐isotope‐labeled COF‐115 and Fourier‐transform infrared spectroscopy. The permanent porosity of COF‐115 was evaluated through low‐pressure N2, CO2, and H2 sorption experiments. Water vapor and carbon dioxide sorption analysis of COF‐115 and the isoreticular imine‐linked COF indicated a superior potential of N‐oxide‐based porous materials for atmospheric water harvesting and CO2 capture applications. Density functional theory calculations provided valuable insights into the difference between the adsorption properties of these COFs. Lastly, photoinduced rearrangement of COF‐115 to the associated amide‐linked material was successfully demonstrated.

Sorption of Carbon Dioxide and Nitrogen on Porous Hyper-Cross-Linked Aromatic Polymers: Effect of Textural Properties, Composition, and Electrostatic Interactions.

Porous hyper-cross-linked aromatic polymers are one of the emerging classes of porous organic polymers with the potential for industrial application. Four different porous polymeric materials have been prepared using different precursors (indole, pyrene, carbazole, and naphthalene), and the composition and textural properties were analyzed. The materials were characterized in detail using different physicochemical techniques like scanning electron microscopy, transmission electron microscopy, nitrogen adsorption at 77 K, Fourier transform infrared spectroscopy, X-ray diffraction, etc. The effect of textural properties and nitrogen species on carbon dioxide and nitrogen adsorption capacities and selectivity was studied and discussed. The carbon dioxide and nitrogen adsorption capacities were measured using a volumetric gas adsorption system. The adsorption data were fitted into different adsorption models, and the ideal absorbed solution theory was used to calculate adsorption selectivity. Among the studied samples, POP-4 shows the highest carbon dioxide and nitrogen adsorption capacities. While POP-1 shows maximum CO2/N2 selectivity of 78.0 at 298 K and 1 bar pressure. It is observed that ultra-micropores, which are present in the prepared materials but not measured during conventional surface area measurement via nitrogen adsorption at 77 K, play a very important role in carbon dioxide adsorption capacity and determining the carbon dioxide selectivity over nitrogen. Surface nitrogen also increases the CO2 selectivity in the dual mode by increasing carbon dioxide adsorption via the acid-base interaction as well as by decreasing nitrogen adsorption due to N-N repulsion.

Large Degree of Variation in Sorption Properties within a System of Isoreticular, Mixed-Ligand Ni- and Co-Based 2-Periodic Metal–Organic Frameworks

Two Ni-based and two Co-based mixed-ligand metal–organic frameworks (MOFs), which are all isoreticular with each other, are shown to have a large variation in nitrogen, carbon dioxide, hydrogen, and water vapor sorption properties, despite their similar structures. The MOFs have 1,2-bis(4-pyridyl)ethane (bpe) as the common ligand with the second ligand being either 2-nitroterephthalate (2-nta) or 2-bromoterephthalate (2-bta) for the Ni-based MOFs or 2-nta or 2-aminoterephthalate (2-ata) for the Co-based MOFs. The four MOFs have the formula [Ni(2-nta)(bpe)(H2O)2]n·2(DMA)n (1), [Ni(2-bta)(bpe)(H2O)2]n·2.8(DMF)n (2), [Co(2-nta)(bpe)(H2O)2]n·2(DMA)n (3), and [Co(2-ata)(bpe)(H2O)2]n·3(DMA)n·(H2O)n (4), respectively, where DMA = N,N′-dimethylacetamide and DMF = N,N′-dimethylformamide. Variable-temperature powder X-ray diffraction (VT-PXRD) studies indicate that the activated MOF structures are different from those of the as-synthesized MOFs, showing that the 2-periodic layers are dynamic upon desolvation. For the same metal ion, the MOF involving the 2-nta ligand has higher sorption, while sorption for the Ni-based MOFs is higher than for the Co-based MOFs. MOF 1 has the highest sorption within the isoreticular series and also has the highest sorption (the highest for water vapor) compared to other MOFs with the same or related ligands.

Studying the Sorption of Carbon Dioxide by Modified Silica Gel with 2-Hydroxyethylcarbamate

Studying the Sorption of Carbon Dioxide by Modified Silica Gel with 2-Hydroxyethylcarbamate

The effect of water-soluble polymers on the dynamics of carbon dioxide sorption by lime sorbents

The effect of water-soluble polymers with different structure on the sorption properties of nonregenerable lime sorbents of carbon dioxide was studied. It was found that the introduction of water-soluble polymers into the sorbents could either decrease or increase the protective power time of the sorbents. To explain the revealed regularities, pore structure of the sorbents was investigated, molecular-dynamic modeling of the carbon dioxide transport was performed, and CO2 diffusion coefficients in water-polymer solutions were calculated. The results of the modeling correlate with the sorption experiment data: a high dynamic sorption capacity of the sorbent is reached after adding a water-polymer medium with a high CO2 diffusion coefficient. The results obtained can be used both to optimize the systems for the recovery of carbon dioxide from gas mixtures and to intensify mass transfer in the systems intended for photo- and electrocatalytic conversion of CO2 to useful products.