H2 Gas Mixture Research Articles

High Purity Hydrogen Separation with HT-PBI Based Electrochemical Pump Operation at 120 °C

Electrochemical Hydrogen Pumps (EHP) provide a unique highly efficient means of separating and compressing hydrogen with continuous steady-state operation. In this paper, we demonstrate the performance of a commercially available, polybenzimidazole (PBI) membrane based platform as a benchmark for ultra-high efficiency performance. A primary gas mixture of CO2 and H2 with a ratio of 4:1 respectively was selected to demonstrate the performance of EHPs with near theoretical Faradaic efficiency with negligible CO poisoning due to reverse water gas shift reaction (RWGS). It was found that humidification of the feed gas at room temperature improved polarization performance while also improving energy efficiency, thus reducing the need for a tightly controlled relative humidity of feed gas. A new perspective on EHP energy efficiency calculation methodology is also provided by including the cell heating requirement in the calculation. In this manner, an overall improvement to the energy efficiency of nearly 20% was realized by dropping the cell temperature to 120 °C while paying no significant penalty to electrochemical performance. Nearly 99.99% pure H2 and 99.93% pure CO2 were produced with a hydrogen yield of 99.34%.

The conversion of naphthalene on SOFC anodes and its impact on the cell performance

The operation of a SOFC with biomass-derived syngas would provide convincing solutions for combined heat and power production from renewable sources. In principle, the tar components in the wood gas can be reformed on Ni-based SOFC anodes, hence, giving access to additional hydrogen as fuel. The investigation of the kinetic-limited conversion process on anodes and its effect on the electrochemical processes of the SOFC is yet still insufficient. This paper presents the experimental study of the conversion of naphthalene on a single planar electrolyte-supported cell with varying temperature and naphthalene concentration. Thereby the impact of the incomplete conversion of naphthalene on open circuit voltage, methane conversion and cell performance is investigated. A 1-D kinetic model reveals the correlation between the slow naphthalene reforming and the open circuit voltage. The adsorption of naphthalene on the Ni catalyst not only impedes the reforming of methane, but also slows down the kinetics of electrochemical reaction. However, the produced hydrogen from steam reforming reaction is still beneficial in terms of preventing Ni re-oxidation under higher fuel utilization in H2 gas mixture.

Superior hot workability of (TiB+TiC)/Ti-6Al-4V composites fabricated by melt hydrogenation

In order to improve the poor hot workability of titanium matrix composites (TMCs), an advanced melt hydrogenation method was introduced in this study. The (TiB+TiC)/Ti-6Al-4 V composites were fabricated by melt hydrogenation which was directly melting alloys in gas mixture of H2 and Ar. Microstructure of as-cast TMCs indicated that melt hydrogenation increased the length of TiB whiskers and aggravated the clustering of reinforcements at primary β grain boundaries, which was due to the increased overheat on melt surface. Hot compression results indicated melt hydrogenation improved the hot workability of TMCs in (α + β) phase region, and the peak stress was reduced from 371 to 271 MPa at 800 °C/1 s−1 and from 119 to 60 MPa at 900 °C/0.01 s−1, respectively, which expanded the optimal hot processing window. Microstructure after hot deformation showed that the proportion of DRX grains was increased from ∼56% to ∼81%, which was mainly attributed to the accelerated migration of DRX grain boundary and the decreased density of dislocations, which was due to the dislocation consumption by DRX formation and the improved mobility of dislocations. Therefore, the improvement of hot workability resulted from the formation of more DRX grains and enhanced mobility of dislocations.

New Preparative Approach to Purer Technetium-99 Samples-Tetramethylammonium Pertechnetate: Deep Understanding and Application of Crystal Structure, Solubility, and Its Conversion to Technetium Zero Valent Matrix.

99Tc is one of the predominant fission products of 235U and an important component of nuclear industry wastes. The long half-life and specific activity of 99Tc (212,000 y, 0.63 GBq g-1) makes Tc a hazardous material. Two principal ways were proposed for its disposal, namely, long-term storage and transmutation. Conversion to metal-like technetium matrices is highly desirable for both cases and for the second one the reasonably high Tc purity was important too. Tetramethylammonium pertechnetate (TMAP) was proposed here as a prospective precursor for matrix manufacture. It provided with very high decontamination factors from actinides (that is imperative for transmutation) by means of recrystallisation and it was based on the precise data on TMAP solubility and thermodynamics accomplished in the temperature range of 3-68 °C. The structure of solid pertechnetates were re-estimated with precise X-ray structure solution and compared to its Re and Cl analogues and tetrabutylammonium analogue as well. Differential thermal and evolved gas analysis in a flow of Ar-5% H2 gas mixture showed that the major products of thermolysis were pure metallic technetium in solid matrix, trimethylammonium, carbon dioxide, and water in gas phase. High decontamination factors have been achieved when TMAP was used as an intermediate precursor for Tc.

Orbital effects on tunnel-electron momentum distributions: Ar and H[formula omitted] studied by electron–ion coincidence momentum imaging

Three-dimensional momentum distributions of tunnel-electrons produced from Ar and H2 in circularly polarized intense laser fields (1035 nm, 35 fs, 2×1014 W/cm2) have been measured by electron–ion coincidence momentum imaging. The photoelectrons recorded with a gas mixture of Ar and H2 exhibit torus-like distributions in the momentum space. Although ionization potentials are similar (15.8 eV for Ar and 15.4 eV for H2), significant differences are identified in the radius and the width of the photoelectron torus recorded in coincidence with the counterpart ions (Ar+ and H2+). The differences are confirmed by theoretical calculations based on the strong-field approximation, showing that the orbital character of ionizing electrons is encoded in the momentum distribution of tunnel electrons.

Pulsed inductive CO2 laser with radio-frequency excitation and influence of the H2 content on the efficiency and lasing temporal characteristics

In 2021, data on the effective pulsed gas discharge inductive CO2 laser with radio-frequency (RF) excitation were published with a pulse output energy of E∼ 1 J (the efficiency η∼ 14.5%) on the gas mixture He:N2:CO2 = 8:2:1. The efficiency of the developed CO2 laser had exceeded the value η∼ 21% at E∼ 350 mJ. At the beginning of 2022, it was shown that xenon addition (Xe = 4%) to the gas mixture made it possible to achieve an efficiency of η∼ 27% at an output energy of E∼ 600 mJ. For the first time, the effect of hydrogen additives in the active medium (He:N2:CO2:H2 and N2:CO2:H2 gas mixtures) was investigated for a pulsed inductive CO2 laser with RF excitation depending on the RF-pumping pulse duration value (τ), which allows the energy and temporal radiation characteristics of the laser to be controlled over a wider range. In addition to those already published, new experimental data have been obtained, namely the output beam profile of the inductive CO2 laser based on He:N2:CO2 = 8:2:1 gas mixture depending on the τ value. The new data will improve our understanding of inductive CO2 laser physics and of the plasma–chemical processes occurring in its active medium. RF current pulses propagated along inductor wires and, thus, an inductive discharge was formed to create a population inversion by IR transitions of CO2 * molecules.

Percolation-assisted coating of metal-organic frameworks on porous substrates

In the past two decades, significant advancements have been made toward thin film fabrication of metal-organic frameworks (MOFs) on porous solid substrates for gas separation and catalysis applications. To enhance the physical and chemical stability of the films, various top-down and bottom-up approaches have been implemented. While both approaches have some advantages, they are mostly limited due to a lack of adhesion with the substrate, cracking of the films, and non-uniform coverages. Therefore, there is a need for improvement in the coating processes for the fabrication of robust, uniform, and scalable films. Here, we develop a novel percolation-assisted coating (PAC) process that combines top-down and bottom-up approaches in a continuous-flow microfluidic device to deposit HKUST-1 on a porous substrate, yielding controlled film thicknesses and mass loading. The PAC process is optimized using a Multiphysics modeling approach to design the microfluidic reactor, which can be readily scaled up and deployed to fabricate MOF films on various porous substrates. The desired thickness in the range of 10–200 μm of the MOF film can be achieved by controlling the residence time and temperature of the reaction mixture. The synthesized film is characterized for physical adhesion using sonication, film coverage using scanning electron microscopy, and porosity using a porosimeter. The performance of synthesized films is benchmarked for the effective separation of 50 vol% CH4–H2 gas mixture with the separation factor of 4. The microfluidic device is also applicable to synthesize films of various MOFs like MOF-5, MOF-505 (also reported here), UIO-66, etc., over a wide range of porous substrates. Lastly, we propose a multi-chamber design of the microfluidic device for high-throughput screening of thin-film growth using the PAC process.

Novel bimetallic 1%M-Fe/Al2O3-Cr2O3 (2:1) (M = Ru, Au, Pt, Pd) catalysts for Fischer-Tropsch synthesis

The main objective of this work was to study the physicochemical and catalytic properties of bimetallic supported catalysts [1%M-Fe/Al2O3-Cr2O3 (2:1) (M = Ru, Au, Pt, Pd)] in Fischer-Tropsch synthesis. Furthermore, the study investigated the effect of noble metal addition to iron-supported catalysts on their physicochemical properties and reactivity. The physicochemical properties of the catalysts were studied using a range of characterization techniques such as X-ray diffraction (XRD), temperature-programmed reduction (TPR-H2), temperature-programmed desorption of ammonia (TPD-NH3) and BET (Brunauer – Emmett - Teller method). The activity tests were performed by Fischer-Tropsch synthesis in a high-pressure fixed-bed reactor using a gas mixture of H2 and CO with a molar ratio of 1:1. The correlation between the physicochemical properties of the investigated catalysts and their catalytic performance in CO hydrogenation was also investigated. The reactivity results showed that the most active system exhibited a high specific surface area, the highest total acidity and was the most reducible catalyst compared to the other catalysts tested. In addition, the AuFe system showed high selectivity towards liquid product formation during CO hydrogenation.

Evaluation of Hydrogen Isotope Transport Performance Using Proton Conductors for Divertor Pumping System

In a DEMO fusion reactor, it is necessary to continuously extract deuterium and tritium from the unburned fuel gas under divertor panels. For the pumping system in the divertor, a new method of transferring hydrogen isotope using proton conductors has been proposed. In this study, we have constructed a new experimental setup using a proton conductor to simulate a divertor pumping system, which extracts hydrogen isotope selectively. Pellets of yttrium-doped cerium oxide and indium-doped zirconium oxide were used as proton conductors. The hydrogen partial pressure on the anode side was set at the atmospheric pressure level and that on the cathode side at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{2}$ </tex-math></inline-formula> Pa. A dc current was applied to the proton conductor cell to selectively transfer hydrogen isotopes. The experiments were conducted in the temperature range of 400 °C- 600 °C. Gas analysis of the transported hydrogen isotopes was carried out using H2 and D2 gas mixture to obtain the transport number. Based on the data obtained from these experiments, the main parameters such as the total area of the proton conductor and the operating conditions are discussed.

Effect of water vapor on deuterium separation by a polymer electrolyte fuel cell

Hydrogen isotopes are a valuable source of hydrogen energy through fusion reactions. The materials used in polymer electrolyte fuel cells (PEFCs), such as the hydrophobic support and Pt catalyst, are essentially the same to those used in the conventional isotope-separation method by water–hydrogen chemical exchange. Here, deuterium (D) separation was performed with a PEFC. A gas mixture of H2 and D2 was supplied while changing the humidity. The hydrogen gas and water vapor from the PEFC were analyzed to investigate the D mass balance. Without power generation, D was separated into the water vapor. This can be explained by the vapor-phase catalytic exchange reaction occurring on the platinum catalyst. The fuel-cell reaction enhanced D separation. A large amount of D (approximately 45%) was transferred to the water vapor during power generation. The present results demonstrate the synergistic effect of vapor-phase catalytic exchange and the PEFC on D separation.

Experimental investigation on the poisoning characteristics of methane as impurity in La0.9Ce0.1Ni5 based hydrogen storage and purification system

In the present work, poisoning effect of CH4 as gaseous impurities in La0.9Ce0.1Ni5 based “Metal Hydride Hydrogen Purification System (MHHPS)” was investigated by varying the impurity level between 10% and 50% by weight, in the H2 gas mixture and by performing cyclic test with 10% impurity. Prototype reactor with 6 embedded cooling tube (ECT) was fabricated and filled with 1.2 kg of La0.9Ce0.1Ni5 for purification study. The experimentation comprises of three steps i.e. absorption, flushing and desorption of gas mixture. The gas samples from each purification stages were analysed using Gas Chromatograph (GC). The system delivered 99.9995% pure hydrogen for 10–20% impure gas mixture. While, for higher impurity level, the purity level of desorbed hydrogen was in the range of 95.9%–99.6%. According to the cyclic study, the amount of hydrogen absorbed was decreased in the range of 0.6 wt% to 0.9 wt% for 50%–90% hydrogen content. For pure hydrogen, the absorption capacity was 1.2 wt%, for absorption condition of 20 °C and 10 bar. The regeneration of the poisoned “Metal Hydride (MH)” bed was performed in two regeneration cycles. The bed poisoning can be decreased significantly, if the desorption temperature is maintained above 90 °C.

Damage associated with interactions between microstructural characteristics and hydrogen/methane gas mixtures of pipeline steels

There is no common standard for blended hydrogen use in the natural gas grid; hydrogen content is generally based on delivery systems and end-use applications. The need for a quantitative evaluation of hydrogen-natural gas mixtures related to the mechanical performance of materials is becoming increasingly evident to obtain long lifetime, safe, and reliable pipeline structures. This study attempts to provide experimental data on the effect of H2 concentration in a methane/hydrogen (CH4/H2) gas mixture used in hydrogen transportation. The mechanical performance under various blended hydrogen concentrations was compared for three pipeline steels, API X42, X65, and X70. X65 exhibited the highest risk of hydrogen-assisted crack initiation in the CH4/H2 gas mixture in which brittle fractures were observed even at 1% H2. The X42 and X70 samples exhibited a significant change in their fracture mechanism in a 30% H2 gas mixture condition; however, their ductility remained unchanged. There was an insignificant difference in the hydrogen embrittlement indices of the three steels under 10 MPa of hydrogen gas. The coexistence of delamination along with the ferrite/pearlite interface, heterogeneous deformation in the radial direction, and abundance of nonmetallic MnS inclusions in the X65 sample may induce a high stress triaxiality at the gauge length at the beginning of the slow strain rate tensile process, thereby facilitating efficient hydrogen diffusion.

Low-pressure THGEM-based operation with Ne＋ H2 Penning mixtures

The operation of Thick Gas Electron Multipliers (THGEMs) in Time Projection Chambers (TPCs) using various gas mixtures has applications in various nuclear and particle physics experiments. Of particular interest in low-energy nuclear physics is study of nuclear reactions involving Ne isotopes. These reactions can be studied using Ne-based gas mixtures at low pressures in TPCs used as active targets for radioactive beams. We report on the low-pressure operation of THGEMs in Ne + H2 gas mixtures. We show that, since the Ne+H2 forms a Penning pair, higher gains with THGEMs are achievable compared to pure neon gas. Moreover, H2 acts as a quench gas allowing for higher THGEMs voltages while producing minimal background in reactions such as fusion compared to carbon-based neon gas mixtures. Detailed electron transport and amplification simulations have been performed and they qualitatively agree with the increased gain H2 provides in the Ne:H2 mixture. The higher THGEM gains that are achieved with a Ne:H2 mixture will enhance the study of Ne-based reactions in active-target detectors that have high-granularity pad planes, leading to higher spatial-resolution heavy-ion track data.

Simple scalable approach to advanced membrane module design and hydrogen separation performance using twelve replaceable palladium-coated Al2O3 hollow fibre membranes

A phase-inversion approach was used to manufacture Al2O3 hollow fibre supports, which were then sintered at 1723 K. The electroless plating technique is developed to prepare palladium-coated Al2O3 hollow fibre membranes for hydrogen separation. Three different scaling-up configurations were produced and tested: single membrane, membrane unit obtained by assembling three membranes, and advanced membrane module obtained by assembling twelve replaceable membranes. The hydrogen flux was investigated under vacuum and without vacuum using a feed gas of pure H2 (100%) and a binary feed gas mixture of H2 (80%) and CO2 (20%) at different feed gas pressures (100–800 kPa), feed gas rate (0.2–6.0 L min−1), and temperature (673–723 K). The hydrogen flux increases from 0.2162 mol m−2 s−1 (feed gas pressure = 600 kPa, feed gas rate = 0.2 L min−1) to 0.4487 mol m−2 s−1 (feed gas pressure = 800 kPa, feed gas rate = 6.0 L min−1) under the binary gas mixture at 723 K by switching from a single to the advanced membrane module, while the hydrogen purity remains above 97.5% throughout the experiment. Some aspects about the scalability of palladium-coated Al2O3 hollow fibre membranes for hydrogen separation are discussed.

Effect of Ar and H2 mixture gas on SnS thin films deposited by radio frequency (RF) magnetron sputtering

The effect of hydrogen on the deposition of SnS films was investigated using conventional radio frequency (RF) magnetron sputtering. The structure of the deposited SnS films was transformed from amorphous to polycrystalline by increasing the partial pressure of H2 gas. Simultaneously, the H2 supply suppressed the formation of an extra S-rich phase and enabled the Sn/S composition to be controlled by exploiting the reaction between hydrogen and sulfur atoms. By increasing the H2 supply, the Sn/S atomic ratio changed from 0.85 (S-rich) to 1.25 (Sn-rich). As the composition changes as a result of hydrogen supplementation, the carrier concentration of the SnS films decreases with increasing H2 gas supply, which may be due to the increase in the enthalpy of formation of tin vacancies. The incorporation of hydrogen in the films was observed using secondary ion mass spectrometry measurements. The amount of incorporated hydrogen did not strongly depend on the amount of H2 supplied. This suggests that hydrogen may not act as a carrier, but simply serves to modify the Sn/S ratio of SnS films using RF magnetron sputtering.

Rh/ZrO2@C(MIL) catalytic activity and TEM images. CO2 conversion performance and structural systematic evaluation of novel catalysts derived from Zr-MOF metallated with Ru, Rh, Pd or In

A set of novel materials, denoted M/ZrO2@C(MIL) (M = Ru, Rh, Pd & In), were prepared by thermal transformation of MIL-140C containing 10% bipyridine linkers (MIL-140C-10), to provide sites for metal coordination within the framework. These materials were transformed into active catalysts for CO2 hydrogenation when heated in a gas mixture of H2 and CO2 (3:1), at 500 °C. The thermal treatment provided high surface area catalysts with high stability and high Ru or Rh metal dispersion which were very effective for the hydrogenation of CO2 to CH4, giving a CH4 production of 3.0–3.7 mol/g Ru/h or 4.2–4.3 mol/g Rh/h (at 400 °C, 33 bar and WHSV 23 L/h/g cat.). PXRD, XPS and TEM indicated that the effective catalysts consisted of nanoparticles of Ru0 (2–5 nm) or Rh0 (6 nm) associated with larger ZrO2 nanoparticles (10–20 nm), which were dispersed upon carbonaceous ribbons. Interestingly, at 250-350 °C, Pd/ZrO2@C(MIL) yielded mainly CO rather than CH4, with some CH3OH. The CH4 and CO production were not stable at 400 °C. TEM results for this catalyst indicated Pd0 and ZrO2 nanoparticles (initially 20 nm and 10–20 nm diameter, respectively). The lower, unstable activity compared to Ru and Rh could have been due to the initially larger Pd particles and their tendency to grow in size with reaction time. In/ZrO2 has mainly been used to catalyse CH3OH production, but In/ZrO2@C(MIL) gave less CH3OH than In/monoclinic ZrO2 and was less selective. At 400 °C In/ZrO2@C(MIL) was a stable, reverse-water-gas-shift catalyst (producing 0.9 mol CO/g In/h at WHSV 20 L/g cat/h). The In was well dispersed in the ZrO2–C and of small particle size. The poor selectivity for methanol may have been due to the tetragonal phase of the ZrO2 and the low surface In concentration.

Electrochemical zirconia-based sensor for measuring hydrogen diffusion in inert gases

Solid-state electrochemical sensors represent a convenient way for solving various electroanalytical tasks. In this work, we present a comprehensive analysis of binary gases composed of hydrogen mixed with an inert gas (He, Ar, N2). Using the fabricated aerometric-type YSZ-based electrolyte, diffusion coefficients for these binary gases were successfully determined in an electrochemical way in a temperature range of 550 °C–750 °C. The obtained results agree well with literature data, showing that the He+H2 gas mixture with highly volatile components exhibit the highest diffusion coefficients, which are around 2 times higher than that for Ar+H2 and N2 + H2.

Improvement on pitting wear resistance of gears by controlled forging and plasma nitriding

In the present investigation, the use of a bainitic steel for forged gears applications and the suitability of different plasma nitriding treatments is discussed. The gears were forged, machined, ground, polished, and nitrided at 500 °C with three sets of N2–H2 gas mixtures, containing 5, 24, and 76 vol.% N2, to develop a nitrided case of approximately 300 μm depth. Gears were characterized before and after the nitriding concerning the phase composition, microstructure, microhardness, fracture toughness, and residual stresses states. Pitting wear tests were performed on a standard Forschungsstelle für Zahnräder und Getriebebau (FZG) test rig. The nitrided gears with 24 and 76 vol.% N2 formed a biphasic compound layer of ε-Fe2-3(C)N and γ′-Fe4N. As the volume fraction of nitrogen in the gas mixture was decreased, the detected content of γ′-Fe4N in the compound layer increased, but a monophasic compound layer was only reached with 5 vol.% N2. The nitrogen rich gas composition increased the surface hardness and decreased the fracture toughness of the compound layer, as they have more ε-Fe2-3(C)N. The diffusion zone of the different nitrided surfaces showed residual compressive stresses. The best performance was obtained in the nitrided gears with 24 vol.% N2, due to the better combination between the surface hardness, fracture toughness, residual stresses, and compound layer thickness. The nitrided gears with 24 vol.% N2 have ten times improvement over the non-nitrided gears, while the nitrided gears with 5 and 76 vol.% N2 have an improvement of three point seven and five point four times.

Effect of N2–H2 Ratio during Conventional Plasma Nitriding of Intermetallic FeAl40 Alloy on Electrochemical Corrosion Parameters in Sulphuric Acid

The intermetallic alloy FeAl40 was plasma nitrided at 575 ∘C for 4 h while varying the N2–H2 gas mixture with nitrogen contents fN2 between 0.1 and 0.9. The effect of the gas mixture on the resulting structure of the nitrided FeAl40 and the associated electrochemical corrosion behaviour in a 0.25 M H2SO4 (pH = 0.3) electrolyte were investigated using different complementary analytical methods such as scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray spectroscopy, electron probe microanalysis (EPMA), electrochemical polarisation and electrochemical impedance spectroscopy. Nitriding significantly changed the corrosion mechanism of FeAl40 alloys in acidic environments, ranging from consistently high material loss in untreated base material to strongly inhibited material loss. This phenomenon was the result of a corrosion product layer formed on nitrided FeAl40 during the corrosion process. Therefore, plasma nitriding reduced the corrosion rate to about 5–7 mm/year compared with 22 mm/year of the untreated FeAl40 base material. A high nitrogen content in the N2–H2 plasma of more than fN2 = 0.3 ensured the formation of protective nitrided layers on FeAl40. In addition, an approach to explaining the effect of the nitrided layer on FeAl materials was presented on the basis of thermodynamic considerations.

Adsorptive purification of CO2/H2 gas mixtures of spent disposable wooden chopstick-derived activated carbon: Optimal synthesis condition

The production of fossil fuel-based H2 by steam reforming and water–gas shift reactions gives the reformed gas containing both hydrogen (H2) and carbon dioxide (CO2). To get pure H2, the CO2 must be removed. In this work, the CO2 was selectively separated from the gas mixture of CO2 and H2 by adsorption process using the spent disposable wooden chopstick (SWC)-derived activated carbon (AC) synthesized by the chemical activation. An appropriate condition for biochar preparation was first explored and then the chemical activation was carried out. Two types of activation chemicals (ZnCl2 and KOH) were employed to activate the biochar at different temperatures (500 – 800 °C). Effects of activation holding time (60 – 150 min) and activation chemical to biochar weight ratio (0.5 – 2.5) were also investigated. The optimal condition for biochar preparation was found at 500 °C and 15 min which can provide the AC yield of 29.5% and CO2 adsorption capacity of 19.2 mg/g from the gas mixtures with 50 mol% CO2 at 25 °C and 1 atm. The AC synthesized by the KOH activation at 700 °C using a KOH/biochar weight ratio of 1.5 for 90 min exhibited the highest CO2 adsorption of 115.7 mg/g for the first use and dropped approximately 20% after 6 adsorption/desorption cycles. Based on the perspective Grand Canonical Monte Carlo (GCMC) simulation, the best synthesized AC exhibited the selectivity of CO2 adsorption 17.6 times higher than that of H2. The adsorption behavior and kinetic model of CO2 adsorption followed the Freundlich isotherm and the pseudo-2nd order model, respectively and the CO2 adsorption occurred via the combined physical and chemical mechanism.