In this study, a novel solid dendrimer amine (hyperbranched polymers) was prepared using mesoporous carbon nitride functionalized by melamine based dendrimer amines. This adsorbent was denoted MDA-MCN-1. The process was stepwise synthesis and hard-templating method using mesoporous silica SBA-15 as a template. Cyanuric chloride and N,N-diisopropylethylamine (DIPEA, Merck) were used for function...

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CH4, C2H6 and C2H4 are the most important outlet gaseous of oxidative couple methane (OCM) reaction and this process is a new technology for conversion of natural gas to ethane and ethylene products. In this study, adsorption of OCM outlet hydrocarbons over 10X zeolite has been examined at equilibrium conditions. Temperature and pressure are the most effective operational parameters in the batc...

Fermentation in the rumen of cattle produces methane (CH4). Methane may play a role in global warming scenarios. The linking of grazing management strategies to more efficient beef production while reducing the CH4 emitted by beef cattle is important. The sulfur hexafluoride (SF6) tracer technique was used to determine the effects of best management practices (BMP) grazing compared with continu...

Hydrothermal, dilute acid, and steam explosion pretreatment methods, were evaluated for their efficiency to improve the methane production yield of three Mediterranean agricultural lignocellulosic residues such as olive tree pruning, grapevine pruning, and almond shells. Hydrothermal and dilute acid pretreatments provided low to moderate increase in the digestibility of the biomass samples, whe...

Methane emissions from mires in all climate–vegetation zones of West Siberia (forest steppe, subtaiga, south taiga, middle taiga, north taiga, forest tundra and tundra) were measured using a static chamber method. The observed fluxes varied considerably from small negative values in forested bogs and palsa to hundreds of mgC m−2 h−1 in ponds and wet hollows. Observed data were consolidated in t...

Mechanistic details of CH4 oxidation were examined on PdO/ ZrO2 catalysts using isotopic tracer methods and measurements of kinetic isotope effects. Normal kinetic isotope effects were observed using CH4/O2 and CD4/O2 reactant mixtures. The (kH/kD) ratio was between 2.6 and 2.5, and it decreased slightly as the reaction temperature increased from 527 to 586 K. These kinetic isotope effects refl...

We describe a three-step bromine-mediated process for oxidative coupling of methane using O2 as oxidant. In the first step, a supported metal bromide solid is treated with O2 to generate Br2 and supported metal oxide. The Br2 thus formed reacts with excess CH4, giving a mixture of CH4, bromomethanes, and HBr. This mixture is passed over a CaO/zeolite composite which condenses bromocarbons with ...

The ability to partially oxidize methane at low temperatures and pressures would have important environmental and economic applications. Although methane oxidation on gold nanoparticles has been observed experimentally, our density functional theory (DFT) calculations indicate neither CH4, CH3, nor H adsorb on a neutral gold nanoparticle. However, by positively charging gold nanoparticles, e.g....

A Zn-exchanged heteropolyacid supported onto silica (Zn-HPW/SiO2) activates methane at 25 °C into Zn-methyl. At higher temperatures and with CH4/O2 or CH4/CO2, it gives methanol and acetic acid respectively.