High-pressure kinetic interactions between CO and H2 during syngas catalytic combustion on PdO

Heterogeneous and Combined Heterogeneous/Homogeneous Combustion Modeling of SOFC Off-Gases

“…This is attributed to the higher H 2 content in case 3 and the well-known self-inhibition of H 2 catalytic ignition. , Finally, the faster drop of X CO,w / X CO,m compared to X H 2 ,w / X H 2 ,m with increasing pressure in Figure indicates a stronger pressure dependence of the CO reactivity compared to that of H 2 . This is in qualitative agreement with recent studies of syngas oxidation on another noble metal (PdO), where the H 2 and CO catalytic reactivities scaled as p 0.10 and p 0.74 , respectively …”

“…This is in qualitative agreement with recent studies of syngas oxidation on another noble metal (PdO), where the H 2 and CO catalytic reactivities scaled as p 0.10 and p 0.74 , respectively. 52 To unravel the chemical impact of H 2 O dilution, additional simulations are carried out by replacing the inlet H 2 O with an artificial species H 2 O*, which has the same transport and thermodynamic properties as H 2 O but does not participate in any catalytic reaction; however, the catalytic pathway is still allowed to produce normal H 2 O via the oxidation of H 2 . To isolate chemical from thermal effects, the wall temperature profiles in Figure 2 are imposed as boundary conditions for the H 2 O* simulations.…”

“…This is in qualitative agreement with recent studies of syngas oxidation on another noble metal (PdO), where the H 2 and CO catalytic reactivities scaled as p 0.10 and p 0.74 , respectively. 52 …”

Combustion, Chemistry, and Carbon Neutrality

“…Reactions that involve catalytic treatment of gaseous species of importance in a combustion context, such as in catalytic combustion, ,− exhaust gas aftertreatment, − syngas conversion, , partial oxidation, ,, dry reforming, ,, chemical looping partial oxidation for H 2 and syngas production, synthesis of ammonia as a noncarbon gaseous fuel, methanation, methanol-to-olefin conversion, and further reactions, present experimental and mechanistic challenges. The complexity of such reaction processes is evident e.g., from the investigation of Li et al on C 2 –C 4 light olefin production from syngas using a specific ZnGaO x spinel catalyst .…”

“…To characterize the catalyst, understand the nature and formation of intermediates, the roles of chemisorbed species, lattice vacancies, and coordination sites, and to describe the mechanism toward a specific product spectrum, a multitude of techniques were combined including HRTEM, SEM, helium ion microscopy (HIM), XRD, EDXS, inductively coupled plasma optical emission spectroscopy (ICP-OES), in situ ambient pressure (AP) X-ray photoelectron spectroscopy (XPS), quasi in situ electron paramagnetic resonance (EPR) and photoluminescence (PL) spectroscopy, temperature-programmed desorption and reduction (TPD, TPR), in situ FTIR, and online GC . Advanced experimental techniques, − ,− , numerical simulations, ,,,− ,,, and/or theoretical methods ,,, have been refined and applied to such heterogeneous reaction systems, and concurrently, methodologies and computational tools have been described to systematically develop and analyze microkinetic mechanisms, ,− also using machine learning and automated mechanism generation approaches. , …”