Following the Structural Changes of Iron Oxides during Reduction under Transient Conditions.

Iron is considered as attractive energy carrier in a carbon-free, circular energy economy. The reduction of iron oxide is crucial for its application as a metal fuel as it determines the efficiency of the cycle. Temperature programmed reduction of α-FeO was monitored by complementary X-ray absorption spectroscopy (XAS) and diffraction (XRD) to obtain the phase composition with high time resolution.

Iron as Recyclable Metal Fuel: Unraveling Oxidation Behavior and Cyclization Effects Through Thermogravimetric Analysis, Wide-Angle X-ray Scattering and Mössbauer Spectroscopy.

The carbon-free chemical storage and release of renewable energy is an important task to drastically reduce CO emissions. The high specific energy density of iron and its recyclability makes it a promising storage material. Energy release by oxidation with air can be realized by the combustion of micron-sized iron powders in retro-fitted coal fired power plants and in fixed-bed reactors under milder conditions.

Hydrogen Production and Carbon Capture by Gas-Phase Methane Pyrolysis: A Feasibility Study.

Invited for this month's cover is the research group of Olaf Deutschmann and the team of Patrick Lott at the Karlsruhe Institute of Technology. The Cover image shows how an electrically heated reactor converts methane from natural gas or biogas into gaseous hydrogen and elemental carbon by means of high-temperature pyrolysis. The transfer of this technology into industrial applications can be a valuable contribution towards a decarbonization of the chemical industry and the establishment of a hydrogen economy.

Soot Formation in Methane Pyrolysis Reactor: Modeling Soot Growth and Particle Characterization.

Methane pyrolysis is a very attractive and climate-friendly process for hydrogen production and the sequestration of carbon as solid material. The formation of soot particles in methane pyrolysis reactors needs to be understood for technology scale-up calling for appropriate soot growth models. A monodisperse model is coupled with a plug flow reactor model and elementary-step reaction mechanisms to numerically simulate processes in methane pyrolysis reactors, namely, the chemical conversion of methane to hydrogen, formation of C-C coupling products and polycyclic aromatic hydrocarbons, and growth of soot particles.

Hydrogen Production and Carbon Capture by Gas-Phase Methane Pyrolysis: A Feasibility Study.

Using natural gas and sustainable biogas as feed, high-temperature pyrolysis represents a potential technology for large-scale hydrogen production and simultaneous carbon capture. Further utilization of solid carbon accruing during the process (i. e.

Thermodynamics and reaction mechanism of urea decomposition.

The selective catalytic reduction technique for automotive applications depends on ammonia production from a urea-water solution via thermolysis and hydrolysis. In this process, undesired liquid and solid by-products are formed in the exhaust pipe. The formation and decomposition of these by-products have been studied by thermogravimetric analysis and differential scanning calorimetry.

Identification of the Reaction Sequence of the MTO Initiation Mechanism Using Ab Initio-Based Kinetics.

The initiation of the methanol-to-olefins (MTO) process is investigated using a multiscale modeling approach where more than 100 ab initio computed (MP2:DFT) rate constants for H-SSZ-13 are used in a batch reactor model. The investigated reaction network includes the mechanism for initiation (42 steps) and a representative part of the autocatalytic olefin cycle (63 steps). The simulations unravel the dominant initiation pathway for H-SSZ-13: dehydrogenation of methanol to CO is followed by CO-methylation leading to the formation of the first C-C bond in methyl acetate despite high barriers of >200 kJ/mol.