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The effects of cobalt in the CeZrO2-supported NiCo (3 wt%, Co/ :Ni=3/2) on the DRM at 750oC were investigated by the transient method and use of 18O2 and 13CO2. Transient kinetic rates of carbon deposition and gasification by the support’s oxygen, TOF (s-1) and concentration of active carbon were determined. Higher TOF and reduced carbon accumulation rates were measured on NiCo than Ni at the initial stage of reaction. However, oxidation of Co with time-on-stream led to lower and higher concentration of active metal sites and deposited carbon, respectively. These results appear important for catalyst design improvements (e.g. metal alloy composition).

This study investigates how morphology, active metal content and oxygen storage capacity of various bimetallic NiCo/CeZrO 2 materials influence their catalytic activity and stability in the methane dry reforming reaction. Catalyst preparation procedure and chemical composition were steered to finally obtain materials, which do not accumulate carbon during the CH 4 /CO 2 reforming reaction. Oxygen storage capacity of the CeZrO 2 catalyst support was identified to play a vital role in retarding carbon accumulation over the tested NiCo/CeZrO 2 materials. This property can be fully developed when a nanocrystalline solid solution of CeO 2 and ZrO 2 is formed. Secondly, a high dispersion of nickel and cobalt is crucial for two reasons: (i) catalysts which contain larger NiCo bimetallic particles (for example with 12–18 wt.% active metal loading) exhibit a low metal-support interphase that results in enhanced coke formation rates; (ii) additionally, only a marginal gain in methane reforming rates are achieved at higher loadings, compared to catalysts with a 3–6 wt.% active metal content. We demonstrated that a NiCo/CeZrO 2 catalyst under relevant operating conditions after 400 h TOS maintains 79 and 84% conversion of CH 4 and CO 2 , with negligible coke accumulation.

The increasing demand for energy and limited reserves of fossil resources as well as climate change will in the near future require the transition from fossil to renewable feedstocks for sustainable production of fuels. In the following text several well-established and also emerging technologies for hydrogen production and its integration into energy-rich carrier molecules, such as methane, methanol, oxygenates, and synthetic petroleum fuel are presented and discussed. Several important factors like the possibility of large-scale production, compatibility with existing distribution and storage infrastructure, efficient energy extraction on demand, and last but not least, tolerable impact on the environment will play key roles. Each of the fuels has its own characteristics, and thus there may not be one single solution, but the coexistence of different fuels, depending on regional boundary conditions.

This study focuses on the hard template synthesis method, which was used to prepare CuO-CeO2 mixed oxide catalysts with 10, 15 and 20 mol % CuO content. KIT-6 silica template was synthesized using a TEOS/Pluronic P123 ratio of 60 and aging temperature of 100 °C. After template removal by NaOH etching, CuO-CeO2 solids exhibited ordered mesoporous structure, which was identified by N2 adsorption/desorption and XRD analyses as a cast of the KIT-6 silica mesostructure. BET surface area of tested materials was in the range of 147–166 m2/g and average CuO particle size between 1.3 and 1.9 nm. High activity and selectivity (over 99%) of these solids was achieved during WGS reaction in the temperature range from 250 to 450 °C.