N2 Gas Mixture Research Articles

New mechanism insight for the hydrogenation of CO/CO2 gas mixtures to hydrocarbons over iron-based catalyst

Iron-based catalysts are the most suitable candidates for converting CO2 or CO2-rich syngas to hydrocarbons. However, several issues about the mechanism of CO2 hydrogenation are still unclear. In this work, we investigated the performance of an iron-based catalyst with H2/CO2, H2/CO/N2 and H2/CO/13CO2/N2 gas mixtures at the same process conditions (T = 270°C, P = 175 psi and SV = 3 NL/h/gcat). The CO2 hydrogenation rate was much lower than that observed for CO hydrogenation. 13CO2 tracer experiments indicated that CO2 is hydrogenated to hydrocarbons via the reverse water-gas shift even when present in small concentration (1.8 vol%). 13C enrichment was observed in both CO and C1-C4 hydrocarbons.

Investigating the Effect of Temperature on Sulfur Deportment in Nickel Laterite Calcination

The majority of the ferronickel production from nickel laterite ores is through the Rotary kiln- electric furnace (RK-EF) process. Calcination and partial reduction of the laterite ore is typically carried out in a rotary fuel fired furnace. Sulfur is one of the most deleterious impurities in nickel alloys and degrades the mechanical properties of the product. Considering the insubstantial concentration of sulfur in laterites, it is assumed that sulfur partially originates from added fuel and reductant in the calcination stage. Investigating the effects of the temperature in the calcination stage on the sulfur distribution can provide valuable information on controlling the level of sulfur in the calcine. In this study, the atmosphere resulted from coal combustion is simulated by purging a gas mixture of N2, CO, CO2, and SO2 to the electrical horizontal tube furnace. The effect of temperature (600, 700, 800, and 900 ⁰C) on the sulfur deportment was studied. Inductively coupled plasma optical emission spectrometry (ICP-OES), and X-ray diffraction tests were used to measure the sulfur content and identify the phase composition of the products. The dominant compound of the calcine that contains sulfur is identified as pyrrhotite. Raising temperature from 600 to 700 ⁰C, increases %S in the calcine from 0.29 to 0.34%; however, promoting the temperature above 700 ⁰C diminishes the sulfur deportation percentage because of decreasing the surface area of solids by recrystallization of magnesia silicate compounds and sintering of oxides.

Photoacoustic studies of energy transfer from ozone photoproducts to bath gases following Chappuis band photoexcitation.

Photoacoustic spectroscopy (PAS) is a sensitive technique for the detection of trace gases and aerosols and measurements of their absorption coefficients. The accuracy of such measurements is often governed by the fidelity of the PAS instrument calibration. Gas samples laden with O3 of a known or independently measured absorption coefficient are a convenient and commonplace route to calibration of PAS instruments operating at visible wavelengths (λ), yet the accuracy of such calibrations remains unclear. Importantly, the photoacoustic detection of O3 in the Chappuis band (λ ∼ 400-700 nm) depends strongly on the timescales for energy transfer from the nascent photoproducts O(3P) and O2(X, v > 0) to translational motion of bath gas species. Significant uncertainties remain concerning the dependence of these timescales on both the sample pressure and the bath gas composition. Here, we demonstrate accurate characterisation of microphone response function dependencies on pressure using a speaker transducer to excite resonant acoustic modes of our photoacoustic cells. These corrections enable measurements of photoacoustic response amplitudes (also referred to as PAS sensitivities) and phase shifts with variation in static pressure and bath gas composition, at discrete visible wavelengths spanning the Chappuis band. We develop and fit a photochemical relaxation model to these measurements to retrieve the associated variations in the aforementioned relaxation timescales for O(3P) and O2(X, v > 0). These timescales enable a full assessment of the accuracy of PAS calibrations using O3-laden gas samples, dependent on the sample pressure, bath gas composition and PAS laser modulation frequency.

Tribological and thermal properties of plasma nitrided Ti45Nb alloy

In this study, the effects of plasma nitriding surface treatment on the structural, tribological and thermal properties of Ti45Nb Beta alloy were investigated experimentally. Plasma nitriding process of Ti45Nb alloy was performed in 25% Ar-75% N2 gas mixture, for treatment times of 1–4 hours at the temperatures of 700–750 °C. The tribological tests of the plasma nitrided alloy were performed in dry sliding conditions. Thermal property measurements were applied to the plasma nitrided samples to determine their thermal conductivity and specific heat capacity. The TiNbN2 phase was observed in the compound layer formed after the nitriding process, and the compound layer and diffusion layer thicknesses increased depending on the nitriding temperature and duration. The highest microhardness was obtained for the sample nitrided at 750 °C for 4 hours and the hardness approximately twice increased compared to the untreated alloy. Due to its high surface hardness and nitride layer with sufficient thickness, the lowest wear rate was obtained for the nitrided sample under these conditions. As a result, the most effective parameter on the wear properties of Ti45Nb alloy after nitriding was determined as the process temperature. After the plasma nitriding process, thermal conductivity, thermal diffusion and specific heat capacity values decreased due to the formation of a nitride layer on the surface with a relatively lower thermal conductivity compared to the untreated alloy.

Effects of hypoxia on the mRNA expressions of TRAIL-mediated cell death related genes in hypoxia-tolerant rodent (Nannospalax nehringi) and some characteristics of these proteins

The aim of the present study was to determine the mRNA expression profiles of TRAIL-mediated cell death related genes of the hypoxia-tolerant rodent Nannospalax nehringi under hypoxia. The nucleotide and amino acid sequences of these genes were identified. Captured Nannospalax nehringi were randomly divided into normoxia and hypoxia groups. The hypoxia group was exposed to a 7% O2 + 93% N2 gas mixture for 52 h, while animals in the normoxia group were housed under normoxic conditions. Total RNAs were isolated from brain and lung tissues. The cIAP-1, cIAP-2, XIAP, DcR1, DcR2, FLIP and OPG genes were PCR amplified, and the cIAP-1, cIAP-2, XIAP, OPG, TRAIL and FLIP genes were sequenced. Sequenced genes were translated into amino acid sequences and compared with reliable sequences of closely similar species. The genes in the brain were regulated for protection against hypoxia; however, the genes in the lung were regulated differently. Many mutations and insertions were observed on the conserved regions of the cIAP-1, cIAP-2, XIAP, OPG and TRAIL genes in N. nehringi. We propose that these gene mutations and insertions contribute to the anti-hypoxic properties of N. nehringi.

Orthorhombic Ta3-xN5-yOy thin films grown by unbalanced magnetron sputtering: The role of oxygen on structure, composition, and optical properties

Direct growth of orthorhombic Ta3N5-type Ta-O-N compound thin films, specifically Ta3-xN5-yOy, on Si and sapphire substrates with various atomic fractions is realized by unbalanced magnetron sputtering. Low-degree fiber-textural Ta3-xN5-yOy films were grown through reactive sputtering of Ta in a gas mixture of N2, Ar, and O2 with keeping a partial pressure ratio of 3:2:0.1 in a total working pressure range of 5–30 mTorr. With increasing total pressure from 5 to 30 mTorr, the atomic fraction of O in the as-grown Ta3-xN5-yOy films was found to increase from 0.02 to 0.15 while that of N and Ta decrease from 0.66 to 0.54 and 0.33 to 0.31, respectively, leading to a decrease in b lattice constant up to around 1.3%. Metallic TaNx phases were formed without oxygen. For a working pressure of 40 mTorr, an amorphous, O-rich Ta-N-O compound film with a high O fraction of ~0.48, was formed, mixed with non-stoichiometric TaON and Ta2O5. By analyzing the plasma discharge, the increasing O incorporation is associated with oxide formation on top of the Ta target due to a higher reactivity of Ta with O than with N. The increase of O incorporation in the films also leads to a optical bandgap widening from ~2.22 to ~2.96 eV, which is in agreement with the compositional and structural changes from a crystalline Ta3-xN5-yOy to an amorphous O-rich Ta-O-N compound.

Effect of Temperature, Time, and Cooling Rate on the Mineralogy, Morphology, and Reducibility of Iron Ore Sinter Analogues

Analogue sinter tablets were produced at temperatures between 1250°C and 1320°C, with a range of hold times and cooling rates. Platy silico-ferrite of calcium and aluminum (SFCA) morphology was identified in samples produced at 1250°C using reflected light microscopy; however, quantitative x-ray diffraction (XRD) identified the presence of the SFCA phase, with no SFCA-I detected. This proves that the platy SFCA morphology common in analysis by reflected light microscopy cannot be attributed to the SFCA-I mineral without further analysis. Micro-XRD and electron probe micro-analysis (EPMA) were carried out on an area of platy SFCA confirming this result. The sinter analogue tablets were reduced in a 30% CO, 70% N2 gas mixture at 900°C in a tube furnace thermo-gravimetric analyzer. The degree of reduction of the tablets in this study was found to be controlled by the porosity of the samples, rather than by the morphology or mineralogy of the bonding phase.

Influence of Relative Humidity on Ethylene Removal Using Dielectric Barrier Discharge

Ethylene gas was decomposed using a dielectric barrier discharge (DBD) plasma reactor for the long-term preservation of fruits and vegetables with a focus on the influence of humidity on ethylene decomposition efficiency. DBD is actively used to produce nonthermal plasma, which is effective in converting C2H4 into CO2 and H2O, through an oxidization process with a high reaction rate because the nonthermal plasma in air contains a large number of chemically active species such as atomic oxygen radicals (O) and hydroxyl radicals (OH). This production of radicals depends on the level of humidity in the air. During the experiment, C2H4 gas was diluted by 200 ppm with an N2 and O2 gas mixture and was fed into the DBD reactor at a 3 L/min gas flow rate. The relative humidity (RH) of the gas was adjusted by the bubbling gas through water. The gas temperature was fixed at 25 °C. The experimental results showed that C2H4 decomposition efficiency was almost independent of RH.

Quantitative study of methane-nitrogen mixed clathrates using gas chromatography and Raman spectroscopy for their detection in icy surfaces of the outer solar system

Multicomponent clathrates may be present at the surface of icy bodies. However, their potential identification remains difficult in the absence of reliable spectral data. In this work, we focus on clathrates synthesized in laboratory from a gas mixture of N2 and CH4, which are particularly relevant for Titan, Triton or Pluto, and investigate their spectral signatures at low temperature (~94 K) and low pressure (down to 2 × 10−6 MPa). The molar composition of the synthesized clathrates for various gas composition were monitored using gas chromatography. Raman scattering from 50 to 4000 cm−1 was carried out, in order to identify discriminating criteria for possible detection by remote and in-situ observations of icy bodies of the outer Solar System. Our experimental results indicate that the identification of CH4-N2 binary clathrate from in-situ Raman spectroscopy may provide a clear determination of clathrate composition.

Phase composition and magnetic structure in nanocrystalline ferromagnetic Fe–N–O films

The chemical and phase compositions and structure of the Fe–N–O films produced by reactive dc magnetron sputtering (in Ar or Ar + N2 gas mixture atmospheres) under different conditions (energy parameters of magnetron, residual pressure in the magnetron chamber after preliminary pumping, operating pressure in gas mixture) have been investigated by energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, and vibrating sample magnetometry. Impurity of nitrogen and oxygen, which are present in the sputtered films, participate in the formation of their phase composition and determine its features. Some phenomena inherent in the nanocrystalline films in the metastable state were found. These are the formation of supersaturated bcc interstitial αFe-based solid solution and precipitation of α’ nitrous martensite with bct crystal lattice. The magnetic structure of the Fe–N–O films, which is characterized by the existence of stochastic domains discovered by correlation magnetometry method, is discussed in terms of the random anisotropy model. It was found that two modes of the magnetic anisotropy field of stochastic domains are formed, which determine the existence of two modes of the coercive field found in the magnetic hysteresis loops.

Effects of nitrogen incorporation on N-doped DLC thin film electrodes fabricated by dielectric barrier discharge plasma: Structural evolution and electrochemical performances

Hydrogenated amorphous carbon-nitride (a-C:H:N) thin films (or N-DLC) were deposited on glass and FTO substrates by a dielectric barrier discharge plasma technique using CH4/N2 gas mixture. The XPS results reveal that as the nitrogen ratio in the CH4:N2 gas mixture increases from 50% to 80%, the nitrogen doping level increased from 5.5 at.% to a maximum value of 11.5 at.% with especially high amounts of pyridinic (6.4 at %), and graphitic (4.7 at %) nitrogen. FEG-SEM results indicate a worm-like porous morphology for the 20%:80% CH4:N2 sample, relying on high amounts of pyridinic and graphitic N, which is a favorable structure to boost the ions diffusion process. This optimized N-DLC electrode with high nitrogen incorporation not only exhibits a nearly electrochemical reversibility with ΔEp (125 mV) and Jpa/Jpc (1.03) in K3Fe(CN)6 electrolyte, but also a fast charge transfer constant (6.59 × 10−4 cms−1). The excellent performance of this electrode is ascribed to the high nitrogen doping level, large surface area, the abundant holes, and the high nano-pore volume possessing excellent electron transfer ability for redox reaction. N-DLC thin film exhibits a promising prospect for biosensors and electrochemical electrode applications.

High Harmonic Generation in Ar and N2 Gas Mixture Using Ultrashort High Power Laser System

High harmonic generation (HHG) has been accepted as a tool for tabletop based generation of light source in the XUV and soft x ray region. HHG can produce coherent optical pulses having pulse duration in the femtosecond or even attosecond time region. In this paper, generation of high harmonics are produced by using high power laser system having optical pulses at 6mj pulse energy with pulse duration of 50fs at 10Hz repetition rate. High harmonics in pure Ar, N2 and mixture of the Ar-N2 are used as a generation medium to produce high harmonics. The harmonic signal is increased or decreased depending on the experimental condition. Harmonic yield produced in Ar is stronger than harmonic yield produced in N2 gas. Generation of high order harmonics are observed up to 35H (~54eV corresponding photon energy), and harmonic order from N2 gas is 33H. The mixture of two gas species cause to enhancement of 35H order, which is weakly observed in pure N2 gas. The mechanism of high harmonic generation is explained that strong harmonic signal generated in pure Ar gas helps increase the ionization rate of N2 gas. Thus, the harmonic signal in Ar-N2 is boosted compared the harmonic signal produced in pure N2. The enhancement factor of harmonic yield is from ~2 to 5 for per harmonic order.

Effect of dopamine on the sensitivity of carotid body to hypoxia induced by acute intermittent hypoxia in rats

Objective: To investigate the sensitivity of carotid body to hypoxia and the effect of dopamine on the sensitivity of carotid body to hypoxia after acute intermittent hypoxia stimulation in rats. Methods: The isolated carotid body-sinus nerve in rat was transferred to incubator, and then the isolated sinus nerve was inhaled into the recorded glass electrode for recording electrical signals. The baseline buffer was bubbled with 95% O 2 + 5% CO 2 mixture gas, and the hypoxic stress was treated with 5% O 2 + 5% CO 2 + 90% N2 mixture gas, hypoxic stimulation was given for 30 seconds, 95% O 2 + 5% CO 2 for 90 seconds, a total of 10 cycles. No less than 5 rats in each group. Results: In this experiment, the electrical activity of sinus nerve isolated from rats was enhanced by hypoxia stimulation after acute intermittent hypoxia, but the response of sinus nerve to hypoxia was inhibited by dopamine. Before acute intermittent hypoxic stress, dopamine also inhibited the firing activity of sinus nerve, but after acute intermittent hypoxic cycle, the inhibition of dopamine on the firing activity of sinus nerve was strengthened. Conclusion: Acute intermittent hypoxia enhances the response of sinus nerve isolated from rats to hypoxia, dopamine inhibits the enhancement of carotid body sensitivity to hypoxia induced by acute intermittent hypoxic.

Separation of noble gases through nano porous material membranes

In this work, the possibility of using nano-porous materials for the separation and storage of noble gases from the off-gas steam generated during the operation of nuclear reprocessing units was theoretically explored. To this end, simulations using the Grand Canonical Monte Carlo (GCMC) method were performed on a wide range of pressure to predict isothermal adsorption at the unit working temperature (323 K) and room temperature (298 K) for a gas mixture of Xe, Kr, N2 and Ar in eight different materials, which all vary in metal ions, pore size and available surface area. This allows us to have a detailed insight at the molecular level of adsorption mechanisms. Results can be used to help designing multi-stage membrane, where only one noble gas will be captured and stored in each stage.

High Pressure Supercritical Carbon Dioxide Separation from its Mixture with Nitrogen at Different Temperatures

Carbon dioxide (CO2) capturing from point sources is currently being proposed as a way to minimize CO2 emissions to the atmosphere. Carbon dioxide is considered one of the greenhouse gases that affects our environment. Legislations are being enforced in many countries to limit CO2 emissions to the atmosphere. Two methods are mostly used for CO2 capturing from flue gases and natural gases; the first method is absorption using amine-based solvents, while the second is membrane separation. The first method is effective for CO2 separation from gas mixtures with low CO2 concentration in the range of 10 to 20%, while the other can handle gas mixture with intermediate CO2 concentration but there is a limit on the CO2 purity. Hence, such methods cannot be used in pre-combustion and oxy fuel technologies where a more concentrated CO2 gas stream is produced. Throughout this work, a new method is introduced to separate carbon dioxide from its mixture with nitrogen (N2) at high concentrations, 90 mol.% CO2 and 10 mol.% N2 gas mixture. A customized high-pressure experimental set-up was built. Three temperature were tested: 15 °C, 25 °C and 38 °C at 150 bar. At such condition CO2 will be in the liquid and the supercritical phase respectively. The composition of the top and bottom streams where analyzed. The amount of CO2 in the top stream was the smallest at the supercritical condition. In addition, the purity of CO2 in the bottom stream was the highest at 38 °C and 150 bars, when CO2 is at the supercritical phase.

Porous carbon nanotube networks and pillared graphene materials exhibiting high SF6 adsorption uptake and separation selectivity of SF6/N2 fluid mixtures: A comparative molecular simulation study

Abstract SF6 and SF6–N2 gas mixtures are well known insulators used in industry applications, but SF6 has to be recovered due to its high global warming potential. In this study, the adsorption of the pure SF6 and N2 fluids and the separation of their mixture with SF6:N2 = 1:9 composition, using three-dimensional porous carbon nanotube networks and pillared graphene materials has been studied by employing Monte Carlo and Molecular Dynamics simulations at ambient temperature and pressure up to 20 bar. The results obtained reveal a significant SF6 uptake and high adsorption selectivity for SF6 over N2, compared to the best performing materials in the literature. The selectivity for SF6 decreases in the case of pillared graphene and strongly depends on the nanotube pillar and graphene layer distances. The saturation capacity of the investigated materials is also achieved at very different pressure ranges, as it has been reflected on the calculated adsorption isotherms. Due to this fact, the translational diffusion coefficients of the adsorbed SF6 and N2 molecules in each material are significantly different at ambient conditions. The results obtained might be used as a springboard towards the rational design of carbon-based materials for the capture of the very potent greenhouse gas SF6.

High-Selectivity Growth of GaN Nanorod Arrays by Liquid-Target Magnetron Sputter Epitaxy

Selective-area grown, catalyst-free GaN nanorod (NR) arrays grown on Si substrates have been realized using liquid-target reactive magnetron sputter epitaxy (MSE). Focused ion beam lithography (FIBL) was applied to pattern Si substrates with TiNx masks. A liquid Ga target was sputtered in a mixture gas of Ar and N2, ranging the N2 partial pressure (PN₂) ratio from 100% to 50%. The growth of NRs shows a strong correlation with PN₂ on the selectivity, coalescence, and growth rate of NRs in both radial and axial directions. The growth rate of NRs formed inside the nanoholes increases monotonically with PN₂. The PN₂ ratio between 80% and 90% was found to render both a high growth rate and high selectivity. When the PN₂ ratio was below 80%, multiple NRs were formed in the nanoholes. For a PN₂ ratio higher than 90%, parasitic NRs were grown on the mask. An observed dependence of growth behavior upon the PN₂ ratio is attributed to a change in the effective Ga/N ratio on the substrate surface, as an effect of impinging reactive species, surface diffusivity, and residence time of adatoms. The mechanism of NR growth control was further investigated by studying the effect of nanoholes array pitch and growth temperature. The surface diffusion and the direct impingement of adatoms were found to be the dominant factors affecting the lateral and axial growth rates of NR, respectively, which were well elucidated by the collection area model.

Calibration data for simultaneous determination of P-V-X properties of binary and ternary CO2 - CH4 - N2 gas mixtures by Raman spectroscopy over 5–600 bar: Application to natural fluid inclusions

The P-V-X properties of two-component fluid inclusions (FIs) are generally determined from microthermometry data using appropriate thermodynamic models (i.e., VX diagrams) and/or equations of state (EoS). However, some limitations can hamper the applicability of this technique such as the small size, low density or complex composition of the analyzed FI. Raman spectroscopy is known as the best-suited alternative method to microthermometry for the investigation of natural FIs because it can provide simultaneously non-destructive qualitative and possible quantitative analyses after specific calibrations. The present work aims to provide calibration data to directly determine the P-V-X properties of binary or ternary mixtures of CH4, CO2, and N2. The variation of spectral features as a function of composition and pressure (or density) was investigated by using Raman spectroscopy coupled with an improved High-Pressure Optical Cell (HPOC) system and a customized heating-cooling stage. From our experimental data, the relative Raman scattering cross-section (RRSCS) of CH4 (νCH4∗) was demonstrated to be constant at 7.73 ± 0.16 over the investigated range of pressure (5–600 bars) and for any composition. This parameter can thus be used for the determination of composition with an uncertainty of ~0.5 mol%. Several calibration equations were calculated for different PX domains, linking the Fermi diad splitting of CO2 (Δ) or the relative variation of the CH4 peak position (νCH4∗) to the pressure (or density) and composition of CO2-CH4, CH4-N2, and CO2-N2-CH4 mixtures at 22 and 32 °C. The pressure and density of the fluids can henceforth be directly measured from Raman spectra with an uncertainty of ~20 bars and ~0.01 g·cm−3, respectively. Our calibration equations were then validated on natural FIs by comparing the results obtained from Raman and microthermometry. We also interpreted the variation of the peak position of CH4 based on the change of intermolecular interaction. Finally, we discussed the applicability of the obtained calibration data into another laboratory by comparing it with the data of pure CO2 and CH4 published in literature. A small shift between calibration curves implies a systematic error which is perhaps due to the difference in the configuration or the day-to-day deviation of the instruments. Therefore, standards of well-known P-V-X properties should be regularly measured to prevent and to correct any variation or shifting of the instrumental responses.

High Temperature Oxidation Behavior of Cr-Al-Si-N Nanocomposite Films Deposited by Filtered Arc Ion Plating Technique.

High temperature oxidation behavior of nanocomposite films is very important characteristics for application of machining and cutting tools. Quaternary Cr-Al-Si-N nanocomposite films with various compositions were deposited onto WC-Co and Si wafer substrates using a filtered arc ion plating technique. The composition of the films were controlled by different combinations of CrAl₂ and Cr₄Si composite target power in a reactive gas mixture of high purity Ar and N₂ during depositions. The instrumental analyses revealed that the synthesized Cr-Al-Si-N films with Si content of 2.78 at.% were nanocomposites consisting of nano-sized crystallites (3-7 nm in dia.) and a thin layer of amorphous Si₃N₄ phases. The nanohardness of the Cr-Al-Si-N films exhibited the maximum values of ~42 GPa at a Si content of ~2.78 at.% due to the microstructural change to nanocomposite as well as solid-solution hardening. The Cr-Al-Si-N film shows superior result of oxidation resistance at 1050 °C for 30 min in air. Based on the XRD and GDOES analyses on the oxidized films, it could be revealed that the enrichment of Al (17.94 at.%) and Cr (26.24 at.%) elements in the film leads to form an Al₂O₃ and Cr₂O₃ layer on the Cr-Al-Si-N film surface. Therefore, in this study, the microstructural changes on the mechanical properties and oxidation behavior with various compositions in the Cr-Al-Si-N nanocomposite films were discussed and correlated with the deposition parameters.

Competitive adsorption characteristics of N2 and CH4 gas mixtures on coal and its geological significance

Coalbed methane (CBM) is an important unconventional natural gas resource and has achieved great advances in recent years. In this study, single and binary component adsorption experiments of N2 and CH4 on dry coal from eastern Yunnan and western Guizhou area were conducted on a high-pressure isothermal adsorption equipment to investigate the competitive adsorption characteristics of N2 and CH4. The results show that absolute adsorption capacity of methane is higher than that of nitrogen for coal samples in this area. Moreover, maximum mixture gas adsorption isotherms lie between the pure N2 isotherms and pure CH4 isotherms. There is an obvious increasing trend for PL as the content of nitrogen increases, it can be ruled out that critical desorption pressure increases along with the increasing nitrogen content in coal seam. This investigation is significative to understand CBM recovery processes considering N2 injection.