Methane is the main constituent of natural gas and can be converted in higher value‐added products for electricity cogeneration. It could be used as a solid membrane reactor (SMR) for application in Alkaline Anion‐Exchange Membrane Fuel Cell (AAEMFC). The investigation for the conversion of methane was based on sodium borohydride (NaBH4) method using Pt/C Basf, Pd/C, Ni/C as catalysts. The electrocatalysts were prepared with 20 wt% of metals loading on carbon. The X‐ray diffraction (XRD) analysis revealed a face‐centered cubic structure (FCC) for Pt/C and Pd/C catalysts, was observed Ni/NiO phases for Ni/C electrocatalyst. The Transmission Electron Microscopy (TEM) exhibited a good dispersion of nanoparticles and some agglomerations on the support, with a mean size of 6.4 nm for Pd/C, 5.7 nm for Ni/C and near to 2 nm size for Pt/C. The experiments with AAEMFC showed that all materials can carry out the reaction spontaneously. Pt/C catalyst presents energy density higher than the other materials. FTIR data suggest that methane was converted into small products organic molecules such as methanol and formate in different potentials for Pt/C, Pd/C, and Ni/C. The products were quantified by Raman spectroscopy. The high conversion efficiency obtained was about 20% at 0.3 V using Pt/C catalyst, the maximum conversion over Pd/C was 17.5% at 0.15 V, associated with the formation of a thin layer of PdO on the catalytic surface. The highest conversion rate (13%) was observed in closed circuit potentials to the short circuit in the cell with Ni/C catalyst. The results suggest that for the selective conversion of methane to methanol are most promising using materials containing Pt or Pd.

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The application of solid electrolyte reactors for methane oxidation to co-generation of power and chemicals could be interesting, mainly with the use of materials that could come from renewable sources and abundant metals, such as the [6,6′- (2, 2′-bipyridine-6, 6′-diyl)­bis (1,3,5-triazine-2, 4-diamine)]­(nitrate-O)­copper (II) complex. In this study, we investigated the optimal ratio between this complex and carbon to obtain a stable, conductive, and functional reagent diffusion electrode. The most active Cu-complex compositions were 2.5 and 5% carbon, which were measured with higher values of open circuit and electric current, in addition to the higher methanol production with reaction rates of 1.85 mol L–1 h–1 close to the short circuit potential and 1.65 mol L–1 h–1 close to the open circuit potential, respectively. This activity was attributed to the ability of these compositions to activate water due to better distribution of the Cu complex in the carbon matrix as observed in the rotating ring disk electrode experiments.

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Methane was converted into C2 and C3 products under mild conditions using a single stage solid electrolyte reactor, using a proton exchange membrane fuel cell as a SER-FC and Pd/C as an electrocatalyst prepared by the reduction method of sodium borohydride. This electrocatalyst has a cubic pattern of palladium centered on the face and an average size of nanoparticles close to 6.4 nm, according to the literature. Differential mass spectrometry reveals the chemical profile of species obtained from the oxidation of methane with ionic currents (Ii) at m/z = 16, 28, 30, 32, 44, 46 and 60. In many cases, Ii can be assigned to more than one species; therefore, complementary ATR-FTIR experiments were performed. The ATR-FTIR spectra confirmed the presence of C2 and C3 compounds such as ethane, ethanol, acetaldehyde, acetic acid and propane. Considering the low amount of water in the reaction medium, these results may be associated with the use of Pd/C electrocatalysts responsible for the activation of the water molecule. The availability of natural gas currently rivals with oil; however, this hydrocarbon is not as versatile as crude oil. [1] The main component of natural gas is methane, the most stable hydrocarbon, with the very high dissociation energy of CÀ H bond (435 kJ mol À 1). [2] Its tetrahedral structure is difficult to polarize; therefore, it makes this molecule almost inert to mild conditions. [3] Turning this gas into higher value-added products is a great goal. Current approaches to utilization of methane involve mainly high-temperature processes to produce syngas (H 2 + CO), which further can be transformed into methanol or fuels. [2] The ethane is a vital building block in the chemical industry with an expectedly of increasing demand in obtaining C2 or longer compounds. [4] The oxidative coupling of methane (OCM) is a direct and exothermic process and not limited by any thermodynamic constraints. [1a]

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