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According to new research, methane emissions contribute 25 percent more to global warming than previously assumed. Methane is a crucial precursor gas of tropospheric ozone, a dangerous air pollutant. Methane emissions are responsible for almost half of the reported growth in tropospheric ozone levels on a global scale. But it plays a vital role as an energy source, therefore, the study of methane cut reservoirs is essential. The injection of air can extract additional energy in high methane-cut reservoirs. The analysis is made to compute the theoretical potential of low air flooding in high methane-cut reservoirs. Computational Fluid Dynamics (CFD) is used to study the impact of injecting air on methane. The presence of carbon dioxide and oxygen when injected into the methane cut reservoir produces high-pressure air injection that may cause significant safety damage such as the potential for corrosion or explosion. Past field studies and reported solutions indicate that there are no insurmountable problems in the execution of high-pressure air injection. The results are harmful and need to take useful safety precautions for the engineers who are interested in experiments. The users of CFD use mathematical laws and models that exactly represent the phenomenon they are dealing with. The pressure induced by the air injection is simulated with the help of the Finite Volume Method (FVM). The velocity field near the outlet arises as higher pressure of air from the inlet is observed, whereas, the pressure near the outlet declines. The findings of this study can help for better understanding of outflow of methane from methane reservoirs.

Transformation of methane, the most abundant and the least reactive compound of natural gas to valuable products is one of the most difficult chemical problems of great practical importance. In Nature, methane monooxygenase enzymes transform methane to methanol in water under physiological conditions. However, chemical analogs for such a transformation are unknown. Here, we show the mild and efficient aqueous oxidation of methane by hydrogen peroxide, an ecologically and biologically relevant oxidant catalyzed by supported μ-nitrido diiron phthalocyanine dimer, (FePc^tBu₄)₂N. This bio-inspired complex containing a stable Fe–N–Fe motif catalyzes the oxidation of methane to methanol which is further transformed to formaldehyde and formic acid as is demonstrated using ¹³CH₄ and ¹⁸O labelling. (FePc^tBu₄)₂N-H₂O₂ system shows a high activity in the oxidation of benzene to phenol which occurs via formation of benzene oxide and exhibits NIH shift typically accociated with biological oxidation. Mechanistic features of oxidation of methane and benzene as well as detected intermediate hydroperoxo- and high valent oxo diiron complexes support an O-atom transfer reaction mechanism relevant to bio-oxidation.

Conversion of methane into high value added chemicals and clean fuels such as methanol under mild conditions is of great importance to the chemical industry. However, traditional thermal catalytic of methane always suffer from harsh reaction conditions and poor product selectivity. Here, we reported photoelectrocatalytic oxidation of methane over BiVO₄/Au/FeCo–LDH under simulated sunlight illumination with ambient‘ conditions. The results demonstrate that BiVO₄/Au/FeCo–LDH exhibits excellent photoelectrochemical properties and catalytic activity. The double-layer capacitance ($C_{dl}$) value of BiVO₄/Au/FeCo–LDH is estimated to be 3.00mF$\cdot$cm${}^{-2}$, indicating its considerable electrochemical active areas. The photocurrent density of BiVO₄/Au/FeCo–LDH reaches up to 1.46mA$\cdot$cm${}^{-2}$ in methane atmosphere. The methanol yield for photoelectrocatalytic oxidation of methane is 8.46 times that of pure BiVO₄, and the corresponding Faraday efficiency is 56.09%. Finally, the reaction mechanism of photoelectrocatalytic conversion of methane to methanol based on hydroxyl radical and methyl radical as intermediate products is proposed. Our finding is expected to provide new insight for the design of active and selective catalysts toward photoelectrocatalytic conversion of methane.

Atmospheric methane, emitted from agriculture sector such as production of rice paddies and farming of livestock populations, is one of the important factors responsible for increasing the average atmospheric temperature leading to global warming. It is, therefore, crucial to comprehend the dynamics of methane emission and its effect on global warming. In this paper, a nonlinear mathematical model is proposed and analyzed to study the increase of average atmospheric temperature (or average global warming temperature) caused by emission of methane due to various processes involved in the production of rice paddies and farming of livestock populations simultaneously. In the modeling process, six variables are considered, namely, the cumulative biomass density of rice paddies, the cumulative density of livestock populations, the cumulative density of methane formed by various processes involved in the production of rice paddies, the cumulative density of methane formed by various processes involved in the farming of livestock populations, the atmospheric concentration of methane and the average atmospheric temperature. It is assumed that both the cumulative biomass densities of rice paddies and livestock populations follow logistic models with their respective growth rates and carrying capacities. The growth rate of concentration of methane in the atmosphere is assumed to be directly proportional to the cumulative densities of various processes involved in the production of rice paddies as well as in the farming of livestock populations. This growth rate also increases with a constant rate from various natural sources such as wetlands, etc. The growth rate of average global warming temperature is assumed to be proportional to the increased level of methane concentration in the atmosphere from its equilibrium value. It is also assumed that this temperature decreases with a rate proportional to its enhanced level from its equilibrium level caused by various natural factors such as rain fall, snowfall, etc.

The proposed model is analyzed using the stability theory of differential equations and numerical simulation. The analysis shows that as the emission of methane from various processes involved in the production of rice paddies and farming of livestock populations increase, the average global warming temperature increases considerably from its equilibrium level. The numerical simulation of the model confirms the analytical results.

Metallization of methane (CH₄) has always been an interesting issue. Here, we report a study on the structure, metallization and superconductivity in K-doped CH₄ under pressure, based on the particle swarm optimization, density functional theory, and density functional perturbation theory. Summarizing the thermodynamical and dynamical stabilities, the electronic band structures, and the electron–phonon interaction calculations, we predicted that K-doped CH₄ in $P{2}_1∕m$ space-group is a metal and a possible superconductor in the pressure range of $70-90$ GPa. The superconducting critical temperature is about 12.7 K at 80 GPa. It was found that the charge transfer from K to CH₄ drives the metallization and mainly contributes to the electron–phonon interaction. The result confirms that CH₄ can become a metal and superconductor under the electron doping and the relative low pressure.

To explore the high-temperature superconductor at low pressures, we have investigated the crystal structures, electronic properties, and possible superconductivity in the case of methane (CH₄) doped by lithium in the pressure range of $0-100$GPa, based on the first-principles calculations. The results show that Li-intercalated CH₄ (Li_x(CH₄)${}_{1-x}$) can realize metallization and superconductivity at low pressures, even 5GPa. We find that there is a charge transfer between Li and CH₄, but the metallization is driven by the change of crystal field induce by doping instead of charge transfer. The critical temperture is predicted from 3.8K at 5GPa for LiCH₄ to 12.1K at 100GPa for Li(CH₄)₄. The low-pressure superconductivity of Li_x(CH₄)${}_{1-x}$ can be further optimized by adjusting component and pressure.

Carbon nanotubes (CNTs) were synthesized by a low-cost floating catalyst (FC) chemical vapor deposition (CVD) method in a horizontal reactor. It was found that iron (III) chloride (FeCl₃) is a high efficient FC precursor for methane CVD to grow CNTs. In this study, the effects of reaction temperature and flow ratio of methane to nitrogen (CH₄:N₂) on the morphology of the CNTs were investigated. The morphological analysis by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that increasing the reaction temperature and flow ratio of CH₄:N₂ grew CNTs of larger diameters. Energy dispersive X-ray (EDX) and thermogravimetric analysis (TGA) were employed to study the purity of the produced CNTs. As shown by the TGA, the highest yield of 74.19% was recorded for the CNTs grown at 1000°C and flow ratio CH₄:N₂ of 300:200.

Owing to the growing concern for alternative sources of energy, the use of brewery spent grains as potential sources of energy (biogas) has been investigated. Brewery derived biowastes (spent grains) were collected from different breweries in southeast Nigeria. These wastes were digested anaerobically in IL laboratory scale digesters over a hydraulic retention time of 14 days (HRT 14) using cow rumen liquor as source of inoculums. An optimization study was carried out by varying some parameters as water dilution and nutrient supplements (wood ash, urea and poultry dropping). The spent grains gave biogas yield of 58-65% methane. Out of the four sets of spent grains used, feed to water ratio of 1:4w/v gave the best biogas yield for three while feed to water ratio of 1:6w/v gave the best yield for one. During nutrient supplementation, highest biogas yield was recorded for wood ash while urea supplements gave the least biogas yield. Increased carbon to nitrogen ratio was found to encourage biogas production. Wood ash increased carbon to nitrogen ratio while urea decreased it. These tests indicated that brewers spent grains can be utilized for biogas production when digested anaerobically and the sludge generated thereafter can provide high quality manure since nitrogen content of the stabilized bio-wastes increased at the end of the digestion as revealed by the proximate analysis.

The carbon structures of phases A and B of methane are investigated through classical molecular dynamics simulations using optimized potentials for liquid simulations all-atom force fields as well as ReaxFF reactive force fields. Both final thermodynamic states were obtained by the proper ramping of temperature and pressure through well-known regions of methane’s phase diagram using the isothermal–isobaric (NPT) ensemble. Our calculated structures are in good agreement with very recent experimental data. The knowledge of these phases is the basis for the study of methane at high pressures.

Although agricultural production contributed about 10% of all greenhouse gas emissions in the United States in 2019, existing agricultural practices are capable of making the sector carbon neutral. Whether American agriculture will ultimately achieve carbon neutrality is ultimately a question of political will, not a scientific one. Given the right policy environment, farms and ranches will be able to cut their emissions and use their land to sequester carbon, while becoming more climate resilient, productive, and profitable…

The catalysts, M (10)/MOR (M=Mn, Fe, Ni), were prepared by impregnation methods and characterized by XRD, NH₃-TPD and NO-TPD. Also, its catalytic activity on CH₄-SCR denitrification reaction was evaluated with fixed-micro reactor. Results showed that Mn (10)/MOR catalysts have good activity and NO conversion rate reached to 30.93% when the temperature is 357°C. The activity of catalyst was influenced by the acidity and the ability of adsorption/desorption of NO.