Catalytic dry reforming over a platinum-based catalyst is described experimentally and numerically in a laboratory pilot-plant flow reactor. The results reveal that coking in the upper part of the catalyst bed and at the entrance of the reactor occurs, depending on the composition of the reaction mixture and the respective temperature. To a significant extent, gas-phase reactions play a role as being the cause for the observed coking behavior in the reforming of methane in the presence of carbon dioxide at high temperatures of 1123−1273 K and at 20 bar. Hydrogen addition can inhibit coke formation better than water addition. The reactor is modeled by a one-dimensional description of the reacting field using elementary-step reaction mechanisms of up to 4238 gas-phase reactions among 1034 species and 58 heterogeneous reactions among 8 gas-phase species and 14 surface-adsorbed species. The study leads an optimized positioning of the catalyst in a technical reformer tube.

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Water‐in‐oil‐in‐water (W/O/W) and water‐in‐oil (W/O) emulsions of paraffin oil were prepared with sorbitan monooleate (Span 80)/polyoxyethylene sorbitan monooleate (Tween 80) or polyethylene glycol monostearate (SG‐6), respectively. The physical characteristics and the absorption of toluene gas in these emulsions were investigated to evaluate the influence of the emulsifier dosage and the oil/water ratio. Both investigated W/O/W emulsions provided high stabilities and low viscosities. The absorption of toluene gas was excellent, with little foam occurring during the absorption. Although the W/O emulsions with 2–5 % SG‐6 were of high stability, their high viscosities strongly limited their application as volatile organic compound absorbents. Stable emulsions consisted of small and uniform droplets and some emulsions underwent mild demulsification after the absorption.

Ni–hexaaluminates exhibiting a high magnetoplumbite or β“‐alumina phase content (>80 wt %) and high specific surface areas (10–30 m2 g−1) were investigated under dry reforming conditions. Ni content and choice of mirror plane cation are the key factors controlling the structure–property relationship in the dry reforming reaction of CH4. The Ni content is favorably kept below a threshold of y=0.25 in ANiyAl12‐yO19−δ, (A=Ba, La, Sr) to ensure controlled nanoparticle formation and to avoid uncontrolled Ni0 nanoparticle growth apart from the support. Sr,Ni and Ba,Ni–hexaaluminates promote high activity of the catalyst in the dry reforming reaction of CH4, but show fast deactivation if the Ni content is maladjusted in the hexaaluminate framework (y≥0.5). La,Ni–magnetoplumbites display much lower activity accompanied by fast deactivation. The use of very high calcination temperatures (1600 °C) resulting in low specific surface area is detrimental to the activity in the dry reforming of CH4, simultaneously higher hexaaluminate phase content obtained undoes catalytic stability, reasoned by Ni0 nanoparticles produced after reduction cannot be stabilized over surface defects typically found on hexaaluminate platelets calcined at moderated temperatures (<1300 °C). As a result, larger metallic Ni ensembles are built up, selectivity to coke is increased and catalytic stability is compromised.

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