Amine CO2 Research Articles

Silica-Supported Hindered Aminopolymers for CO2 Capture

Sterically hindered amine solutions have been studied extensively for CO2 capture via absorption due to their high theoretical amine efficiencies (1 CO2/N) and weak amine–CO2 species formed. More r...

2D/3D amine functionalised sorbents containing graphene silica aerogel and mesoporous silica with improved CO2 sorption

This work investigates the performance of amine functionalised 2D/3D sorbents for CO2 capture. The 2D/3D structures were based on a combination of flake-like reduced graphene-silica oxide (G-Si) aerogel and rod-like mesoporous silica SBA-15. The G-Si aerogel formed mainly silica microporous structures which enveloped graphene sheets. The SBA-15 displayed the classical rod-like mesoporous features with high pore volume. The addition of G-Si aerogel to SBA-15 for the amine functionalised samples significantly reduced the combined total surface area and pore volume. Interestingly, the CO2 sorption capacity increased and peaked for samples containing G-Si aerogel/SBA-15 at 1:20 mass ratio (4.7 wt%), though declining thereafter. This counterintuitive effect of increasing CO2 sorption capacity but decreasing surface area and pore volume was attributed to the special morphological features of the 2D/3D sorbent assembly. At these optimal conditions, the flake-like G-Si aerogel was well intercalated with the rod-like SBA-15. As a result, the inter-particle space formed between the flake-like and rod-like assembly accommodated TEPA which facilitate the mass transfer and reaction between the amine groups and CO2. These special 2D/3D morphological features delivered high CO2 sorption capacity of 6.02 mmol g−1. The 2D/3D sorbents were also very stable under sorption and desorption cycles whilst heat of sorption were up to 22% lower than the analogue 3D SBA-15/TEPA sorbent.

Electrochemical Decomposition of Nitrosamines Formed in CO2 Capture Systems

Nitrosamines can form from the reaction of NOx with secondary amines and accumulate in the amine solvent loop and waterwash sections of amine CO2 capture systems. Nitrosamines, as a class of compounds, have been reported to be mutagenic, cytotoxic, genotoxic and carcinogenic. Nitrosamines are an emerging environmental concern if their formation and emission from operating CO2 capture systems cannot be better understood and controlled. In this study, a stationary carbon electrode material inside an electrochemical cell will be used to target and adsorb the nitrosamines from a washing water solution and decompose them into less harmful compounds. This preliminary study shows that the UKy-CAER developed carbon xerogel (CX) electrode material has a high adsorption capacity and can decompose a high percentage of nitrosamines with a minimal amount of charge passed. This electrochemical strategy can be effective for the removal of nitrosamines from wastewater and amine-CO2 capture waterwash streams.

Ultrasound-assisted amine functionalized graphene oxide for enhanced CO2 adsorption

The present study discusses a novel ultrasound promoted amination technique to functionalize graphene oxide (GO) for CO2 adsorption. Graphene oxide was synthesized following the modified Hummer’s method. The developed functionalization technique integrates the advantages of low-frequency ultrasonic physical activation with the chemical functionalization using tetraethylenepentamine (TEPA). Acoustic treatment exfoliates the clusters of graphene oxide and enhances the surface area for the subsequent amine functionalization and CO2 adsorption. Changes in textural properties, surface functionalities, thermal stability, and elemental compositions were examined before and after activation of graphene oxide. The characterization results revealed substantial increment of N content, from 0.08 in pristine to 4.84% in functionalized GO and the subsequent reduction in surface area from 289 to 198 m2/g in the functionalized GO, indicating attachment of TEPA to GO structure. CO2 adsorption experiments were conducted under diluted CO2 with the partial pressure of 0.10 atm. at 338 K and the results revealed that ultrasonic-TEPA activated GO possessed enhanced adsorption capacity of 1.2 mmol g−1 over pristine GO. While pristine GO could only achieve the maximum adsorption capacity of 0.3 mmol g−1 at 303 K. Besides, the sonochemically modified adsorbent showed stable cyclic adsorption-regeneration performance with only 1% reduction in adsorption capacity after 10 cycles. Finally, the effectiveness of the developed physicochemical activation technique was determined by comparing its adsorption capacity with the adsorbents found from literature.

Amine-impregnated carbon aerogels with ultra-high pore volume synthesized by pH adjusting for efficient CO2 Capture

Carbon aerogels with ultra-high pore volume and meso/macro pores were successfully synthesized by using silica hard templating combined sol–gel method by controlling the pH value of the initial reaction solution. High loadings (65–80 wt%) of TEPA (tetraethylenepentamine) and PEI (polyethyleneimine) were impregnated into CA with a high pore volume of 5.7 cm3/g for CO2 adsorption, respectively. The effects of amine loading, CO2 concentration, adsorption temperature, and moisture on the CO2 adsorption performance of the amine-loaded CA sorbents were comparatively investigated. The results showed that the CA with ultra-high pore volume enabled excellent CO2 adsorption capacity and fast kinetics (5.93 mmol/g and 4.70 mmol/g within 2.5 min for the case of TEPA and PEI respectively at 75 °C under 10% dry CO2). The sorbents exhibited good recycle-ability both in dry and humid conditions. Under humid conditions, the diffusion resistance of the sorbents at the initial stage of CO2 adsorption was observed. This study suggests that CA with large pore size could be utilized as promising amine sorbent for post-combustion CO2 capture.

Control of gas permeability by transforming the molecular structure of silk fibroin in multilayered nanocoatings for CO2 adsorptive separation

Carbon dioxide (CO2) is considered one of the causes of global warming because anthropogenic CO2 concentration in the atmosphere has greatly increased. The objective of this work was to design silk fibroin (SF) and graphene oxide (GO) membranes with very high CO2 gas capture characteristics and high gas selectivity toward nitrogen rather than CO2 gas, and to demonstrate the effect on transforming the SF secondary structure at the molecular level. GO-NH3+/SF multilayer nanocoatings were fabricated by automatic spray-assisted layer-by-layer (LbL) assembly with physical molecular interaction between GO-NH3+ and SF. We demonstrated transformation of the SF secondary structures in GO-NH3+/SF LbL-assembled nanocoatings with MeOH solvent treatment. After MeOH treatment, the SF secondary structures in the GO-NH3+/SF LbL-assembled nanocoatings preferred β-sheets to random coils. This phenomenon affects the internal amine groups and CO2 transport. The MeOH-treated GO-NH3+/SF LbL-assembled nanocoatings have high β-sheet content, and the gas permeability of the nanocoatings was quite different. Before the predominance of the β-sheet, CO2 gas permeated twice as fast as nitrogen (N2) gas in the GO-NH3+/SF LbL-assembled nanocoatings. On the other hand, CO2 gas was transmitted 10-times slower than N2 gas in MeOH-treated GO-NH3+/SF LbL-assembled nanocoatings. In other words, we successfully fabricated a CO2 adsorptive separation membrane with GO-NH3+ and SF.

Techno-economic analysis of CO2 capture from a 1.2 million MTPA cement plant using AMP-PZ-MEA blend

This research covered the rate-based process simulation (ProMax® 4.0) and techno-economic analysis of carbon dioxide (CO2) capture from a 1.2 million metric tonne per annum cement plant using aqueous 2 kmol/m3 AMP-1 kmol/m3 PZ-2 kmol/m3 MEA blend. The waste gas composition for this study was provided by a cement plant from Quebec, Canada. The effect of amine type, energy penalty, and CO2 capture efficiency (50% to 90%) on the capture costs (US$/tonne CO2 and US$/tonne cement) were investigated. Sensitivity analysis on the impact of CO2 capture plant, carbon tax (US$ 20 to US$ 40 per tonne of CO2), CO2 sales price (US$ 10 to US$ 40 per tonne of CO2), energy penalty and CO2 capture efficiency on the cement price was also investigated. Results revealed that at 90% CO2 capture efficiency, the capture costs of AMP-PZ-MEA (US$77.34/tonne CO2 and US$44.94/tonne cement) is lower than that of MEA (US$93.23/tonne CO2 and US$54.17/tonne cement). Results also revealed that the total equipment cost and capital expenditure (CAPEX) of MEA system (US$ 29.76 million and US$ 147.12 million) higher than that of AMP-PZ-MEA blend (US$ 23.39 million and US$ 127.59 million).Cash flow analysis showed that without adding a CO2 capture unit to a cement plant, carbon tax increased the cement price up to 22.9%. However, a combination of the high carbon tax, high CO2 sales price, low energy penalty, and high capture efficiency increased the cement price up to 1.2% for the MEA system but reduced the cement price up to 5% for the AMP-PZ-MEA system. This comprehensive study shows that a cost-effective and energy-efficient amine blend, energy penalty, CO2 capture efficiency, carbon tax, and CO2 sales prices are all integral towards reducing the cement price while significantly reducing the CO2 emissions.

Water Enhancement in CO2 Capture by Amines: An Insight into CO2–H2O Interactions on Amine Films and Sorbents

Water, a component in flue gas, plays a significant role in CO2 capture through a complex interaction between water molecules and adsorbed CO2 on amine sorbents. To determine how the H2O–CO2–amine interactions affect amine efficiency and the binding energy of adsorbed CO2, we used in situ infrared spectroscopy (IR) to determine the structure of adsorbed CO2 and H2O as well as their relations to adsorption/desorption kinetics and CO2 capture capacity on tetraethylenepentamine (TEPA) films and Class I amine (i.e., impregnated) sorbents. H2O enhanced amine efficiency of TEPA films and sorbents by increasing the accessibility of secondary amine sites to CO2 and promoting the formation of hydronium carbamate and carbamic acid. CO2 adsorbed on the surface of the TEPA film as a weakly adsorbed CO2 in the form of hydronium and ammonium–carbamate with a low IR intensity of hydrogen bonding (−OH···–OOC or −NH···–OOC) between hydronium/ammonium ions and carbamate ions. CO2 adsorbed on the middle layers (i.e., 0.2–0....

Modeling and experiments of equilibrium solubility of carbon dioxide in aqueous N-(2-hydroxyethyl) pyrrolidine solution

Abstract In this work, the equilibrium CO2 solubilities of the aqueous N-(2-hydroxyethyl) pyrrolidine (N-(2-HE) PRLD) at different concentrations (1.0 mol/L–5.0 mol/L) were measured at different temperatures (298 K–333 K) and pressures (8 kPa–101 kPa), using a vapor–liquid equilibrium apparatus. Four semi-empirical thermodynamic models (Cf model, Kent–Eisenberg model, Hu–Chakma model and Li–Shen model) were used to correlate and predict the CO2 solubility data of the N-(2-HE) PRLD-CO2–H2O system. The results showed that the Hu–Chakma model, which is one of the models that incorporates the effect of amine concentration and CO2 loading, and accounted for nonideality caused by higher temperature, species concentrations and CO2 loadings, was best able to predict results that are in agreement with the experimental vapor–liquid equilibrium measurements in this work.

Design of energy efficient reactive solvents for post combustion CO2 capture using computer aided approach

The reduction of CO2 emissions has become a challenge due to rapid economic growth all over the world. Growing concerns on this issue have led the researcher to develop and implement several strategies including one very promising strategy involving CO2 capture from power plants. This paper presents a Computer Aided Molecular Design (CAMD) technique to design new alternative solvents as replacements for commonly used solvents during the post combustion carbon capture process in power plants, which is often costly and energy intensive. The CAMD technique can quickly identify the most suitable solvents and avoid spending resources on infeasible solvent replacements. In this study, the reverse design approach is used where, first, the criteria of the targeted solvents are identified and then the desired solvent candidates generated. The methods for this work consists of five steps: 1) Problem formulation, 2) Generation of single reactive solvent candidate using ProCAMD tools in ICAS software, 3) Prediction of the reaction mechanism between the potential amine solvent candidate and CO2 using the zwitterion mechanism and base-catalysed hydration mechanism, 4) Evaluation of process performance by calculating the heat required for the solvent regeneration process, and 5) Selection of the best solvent candidate based on its desired process performance. The result of this study reveals that 25 amine-based solvents for the chemical absorption process were successfully generated from the amine and alcohol functional groups. By using the proposed solvent, significant savings on regeneration energy, up to 31.4%, could be achieved compared to the conventional solvent, MEA. The percentage average absolute deviation (AAD) of the property prediction model that this study used to estimate the value of heat of formation is 4.67%. This finding is important to further reduce the regeneration energy, which makes the CO2 capture process costly, and achieve a more sustainable and cleaner environment.

CO2 Capture Partner Molecules in Highly Loaded PEI Sorbents

Decoupling amine loading from diffusion resistance is one of the main challenges in the development of immobilized amine CO2 sorbents. Water has been reported to serve this goal, alleviating CO2 diffusional hindrance in highly loaded amine sorbents. Acting as a mass transport facilitator, water is not the only partner molecule able to enhance bulk CO2 diffusion. Herein, we show that the enhancing effect of methanol is comparable to that of water in polyethylenimine-based sorbents. Other molecules, such as ethanol, isopropanol, and chloroform, were also examined but did not appear to facilitate CO2 transport and uptake. Based on a comparison of the Hansen solubility parameters of these molecules, it appears that polarity plays a crucial role in enhancing CO2 diffusion together with molecular hindrance and hydrogen bonding to a lesser extent.

Multi-Objective Optimization for Solid Amine CO2 Removal Assembly in Manned Spacecraft

Carbon Dioxide Removal Assembly (CDRA) is one of the most important systems in the Environmental Control and Life Support System (ECLSS) for a manned spacecraft. With the development of adsorbent and CDRA technology, solid amine is increasingly paid attention due to its obvious advantages. However, a manned spacecraft is launched far from the Earth, and its resources and energy are restricted seriously. These limitations increase the design difficulty of solid amine CDRA. The purpose of this paper is to seek optimal design parameters for the solid amine CDRA. Based on a preliminary structure of solid amine CDRA, its heat and mass transfer models are built to reflect some features of the special solid amine adsorbent, Polyethylenepolyamine adsorbent. A multi-objective optimization for the design of solid amine CDRA is discussed further in this paper. In this study, the cabin CO2 concentration, system power consumption and entropy production are chosen as the optimization objectives. The optimization variables consist of adsorption cycle time, solid amine loading mass, adsorption bed length, power consumption and system entropy production. The Improved Non-dominated Sorting Genetic Algorithm (NSGA-II) is used to solve this multi-objective optimization and to obtain optimal solution set. A design example of solid amine CDRA in a manned space station is used to show the optimal procedure. The optimal combinations of design parameters can be located on the Pareto Optimal Front (POF). Finally, Design 971 is selected as the best combination of design parameters. The optimal results indicate that the multi-objective optimization plays a significant role in the design of solid amine CDRA. The final optimal design parameters for the solid amine CDRA can guarantee the cabin CO2 concentration within the specified range, and also satisfy the requirements of lightweight and minimum energy consumption.

MEA and Piperazine Corrosion of Carbon Steel and Stainless Steel

Two methods were developed to measure the corrosion of 1010 carbon steel and 316L stainless steel in solutions of ethanolamine, piperazine, and several other linear amines at high temperature and pressure. The effect of amine concentration, CO2 loading, and temperature were measured. The first method uses Swagelok® steel cylinders heated in ovens to accelerate corrosion of the metal surface, which is then estimated by measuring dissolved metal. Although the steel cylinder method gave reasonable corrosion rates for 316L SS, it significantly under predicted the corrosion rate of 1010 CS. This is likely due to the weakly adhering passive film that was protective only at the stagnant conditions in the non-agitated cylinders. The second method uses an electrical resistance probe to measure corrosion in a bench-scale thermosiphon apparatus, which was constructed to simulate more realistic flow conditions. Both methods were used to examine a series of linear amines and their results were compared. Corrosion of the electrical resistance probe by a variety of degraded piperazine solutions from pilot plants was measured. Loading was found to be the dominant factor in piperazine corrosion. Counterintuitively, corrosion rates of stainless steel decrease at high loadings, probably due to the formation of a FeCO3 film. Degraded piperazine was only slightly more corrosive than clean piperazine at most conditions. Over a wide variety of conditions, 1010 carbon steel showed lower corrosion rates in piperazine solutions than 316L stainless steel.

Density and Viscosity of Partially Carbonated Aqueous Solutions Containing a Tertiary Alkanolamine and Piperazine at Temperatures between 298.15 and 353.15 K

Measurements for the density and viscosity of partially carbonated solutions containing water, piperazine (PZ), and a tertiary amine, which was either dimethylaminoethanol (DMAE) or 2-diethylaminoethanol (DEAE), were conducted with total amine mass fractions of 30% and 40% over a temperature range from 298.15 to 353.15 K. Density and viscosity correlations of these mixtures were developed as functions of amine mass fraction, CO2 loading, and temperature. For both systems investigated, the average absolute relative deviations of the experimental data from these correlation are approximately 0.2% for density and 3% for viscosity. The correlations will be useful for thermodynamic analysis and computer simulations of carbon capture processes utilizing these promising blended amine systems.

The Role of Bicarbonate in Ion Speciation Plots in DEAB and Blended MEA-DEAB Systems, an NMR Study

The MEA-DEAB-CO2-H2O solutions contain complex ions in the solution. Carbamate (RNH-COO-) and bicarbonate (HCO3-) anions are the major format of CO2 dissolved in the solutions. The ion concentrations of both components are constrained by the reaction equilibrium and VLE model of CO2-amine interactions. For the MEA-CO2-H2O systems, the majority of [CO2]0 is carbamate. For the DEAB systems, the majority is bicarbonate. The blended amine system such as MEA-DEAB-CO2-H2O contains both carbamate and bicarbonate at different ratios, which is affected by variations of amine ratio, CO2 loading and operation temperatures. This work summarized VLE plots from 13C NMR analysis of single and blended amine solutions, both in room temperature (24°C) and higher temperature (70°C) to detect trend of the ratio of bicarbonate vs carbamate in the blended amine (MEA-DEAB) systems under both absorption and regeneration conditions. These experimental data indicated the carbamate exchange reaction is endothermic. With increase of temperature, ratio of bicarbonate increased accordingly and that of carbamate decrease. The increased concentrations of bicarbonate can facilitate the amine regeneration with reduced heat duty.

Research on Urea Linkages Formation of Amine Functional Adsorbents During CO2 Capture Process: Two Key Factors Analysis, Temperature and Moisture

Amine functional adsorbents as a promising choice for practical CO2 capture applications had attracted extensive interest, but the formation of urea linkages between amine functional adsorbents and CO2 is extremely adverse to its development for practical application. Therefore, through learning the mechanism of urea linkages formation between amine functional adsorbents and CO2 will be useful to promote its practical application. Temperature and moisture are two key factors influencing the formation of urea linkages between amine functional adsorbents and CO2. In this study, we found that temperature obviously affected the kinetics of the formation of urea linkages, and three key temperature points were discerned; when the temperature reached 95, 115, and 121 °C, the urea linkages formation rate obviously increased. Especially at 121 °C, the formation rate would reach a very high extent that led to serious degradation of amine functional adsorbents, and badly damaged the cyclic adsorption stability of am...

Effect of Post‐Functionalization Conditions on the Carbon Dioxide Adsorption Properties of Aminosilane‐Grafted Zirconia/Titania/Silica‐Poly(amide‐imide) Composite Hollow Fiber Sorbents

AbstractIn this study, 3‐aminopropyltrimethoxysilane (APS) was used as a grafting agent in three solvents with different polarities for post‐functionalization of a ZrO2–TiO2–SiO2/poly(amide‐imide) composite hollow fiber sorbent (Zr–Ti–Si/PAI‐HF) at ambient temperature. The same fiber at two different states: (i) wet (as‐spun) and (ii) dry were used for amine grafting. The influence of the polarity/nature of various solvents such as acetone, ethanol, and toluene on the CO2 sorption characteristics of wet and dry Zr–Ti–Si/PAI‐HF fibers was investigated accordingly. Several parameters such as grafting time (1–4 h), amine concentration (10–50 wt %), and solvent type (acetone, ethanol, and toluene) were systematically varied. The CO2 sorption capacity and breakthrough tests were performed under simulated flue gas conditions for grafted fiber composites. Our results indicate that the CO2 sorption capacity of amine‐grafted Zr–Ti–Si/PAI‐HF strongly depends on both the type of solvent and the state of the fibers (i.e., dryness or wetness). The APS grafting of wet fibers performed in toluene led to high amine loading and CO2 capacity (1.40 mmol g−1), whereas dry fibers gave rise to a relatively low CO2 capacity (0.90 mmol g−1). In contrast, dry fibers functionalized in either acetone or ethanol exhibited higher CO2 capacity compared to the wet fibers prepared in the same solvent. By using ethanol as a solvent, the solvolysis of the Si−O−Si linkages is much faster than the competitive condensation reaction between the silanol groups (Si−OH) of APS moieties and hydroxyl group (OH) of the ethanol, which leads to the lower siloxane formation. In the case of acetone, a dense polymeric network is formed under condensation reaction between an acetone molecule and the amine moieties, thus reducing the amount of primary amine groups available for interacting with the CO2 molecules.

Amine hybrid aerogel for high-efficiency CO2 capture: Effect of amine loading and CO2 concentration

The objective of this research was to develop a high-performance CO2 adsorbent by a simple, cost-effective and environmental-friendly route based on amine hybrid aerogel. A new amine hybrid titania/silsesquioxane composite aerogel (AHTSA) was prepared by a one-pot sol-gel process followed by supercritical drying (SCD). The wet gel was obtained by orderly mixing all the reactants in a container without adding any catalyst. SCD was conducted without contaminant emission. Effects of amine loading and CO2 concentration on pores structure and CO2 adsorption performance of AHTSA were investigated. Higher amine loading leads to lower specific surface area and mesopore volume of AHTSA, due to the increase of large pores and diminishment of mesopores when increasing the amine loading. Resulting from the sharp decrease of the surface area, overdosing of the amine precursor negatively affects the surface amine content of AHTSA and thus reduces its CO2 adsorption capacity. High CO2 concentration favors the CO2 adsorption capacity and rate as concentrated CO2 favors the CO2 diffusion in the pore space of the adsorbent, enhances the interaction between CO2 and surface amine groups. The dry CO2 adsorption capacity of AHTSA increases from 1.64, 4.19 to 6.66mmol/g when the CO2 concentration of the mixture gas varies from ∼400ppm (air), 1% to 10%. Short adsorption halftime and high amine efficiency of AHTSA with different CO2 concentrations reveal that AHTSA is a dynamic and effective adsorbent for CO2 capture, even direct air capture.

Spectroscopic Investigation of the Mechanisms Responsible for the Superior Stability of Hybrid Class 1/Class 2 CO2 Sorbents: A New Class 4 Category.

Hybrid Class 1/Class 2 supported amine CO2 sorbents demonstrate superior performance under practical steam conditions, yet their amine immobilization and stabilization mechanisms are unclear. Uncovering the interactions responsible for the sorbents' robust features is critical for further improvements and can facilitate practical applications. We employ solid state (29)Si CP-MAS and 2-D FSLG (1)H-(13)C CP HETCOR NMR spectroscopies to probe the overall molecular interactions of aminosilane/silica, polyamine [poly(ethylenimine), PEI]/silica, and hybrid aminosilane/PEI/silica sorbents. A unique, sequential impregnation sorbent preparation method is executed in a diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) setup to decouple amine binding mechanisms at the amine-silica interface from those within bulk amine layers. These mechanisms are correlated with each sorbents' resistance to accelerated liquid H2O and TGA steam treatments (H2O stability) and to oxidative degradation (thermal stability). High percentages of CO2 capture retained (PCR) and organic content retained (OCR) values after H2O testing of N-(3-(trimethoxysilyl)propyl)ethylenediamine (TMPED)/PEI and (3-aminopropyl)trimethoxysilane (APTMS)/PEI hybrid sorbents are associated with a synergistic stabilizing effect of the amine species observed during oxidative degradation (thermal gravimetric analysis-differential scanning calorimetry, TGA-DSC). Solid state NMR spectroscopy reveals that the synergistic effect of the TMPED/PEI mixture is manifested by the formation of hydrogen-bonded PEI-NH2···NH2-TMPED and PEI-NH2···HO-Si/O-Si-O (TMPED, T(2)) linkages within the sorbent. DRIFTS further determines that PEI enhances the grafting of TMPED to silica and that PEI is dispersed among a stable network of polymerized TMPED in the bulk, utilizing H-bonded linkages. These findings provide the scientific basis for establishing a Class 4 category for aminosilane/polyamine/silica hybrid sorbents.

Increasing mesoporosity by a silica hard template in a covalent organic polymer for enhanced amine loading and CO2 capture capacity

Solid sorbents for chemisorptive carbon dioxide uptake in post-combustion scenarios require strong binding groups like amines. Post-synthetic impregnation of reactive amines requires large pore volumes. Covalent organic polymers (COPs) are microporous (or narrow mesoporosity) network polymers with physisorptive behavior. Herein as the first of such attempt in porous organic polymers, we modified COP-1, which is an inexpensive, scalable porous polymer for effective amine loading. By expanding the pore of COP-1 through hard templation by silica, the surface area and pore volume are increased by 2.3 and 2.9 times, respectively. It was shown that the increase of pore volume was mostly from pores larger than 5 nm and it correlates well with the silica particle size (12 nm) and the inter-particle pore sizes of silica (31 nm). As a result, amine impregnated Si-COP-1 adsorbs CO2 with the increase of 2.44 at 273 K and 4.06 times at 298 K (at flue gas relevant partial pressure of 0.15 bar) over the parent COP-1. Our results show the possibility of tuning porosity for developing industrially feasible CO2 capturing sorbents.