The experimentally determined temperature programmed desorption profile of CO from Fe(100) is characterized by four maxima, i.e., α1-CO, α2-CO, α3-CO, and β-CO (see e.g., Moon et al., Surf. Sci. 1985, 163, 215). The CO-TPD profile is modeled using mean-field techniques and kinetic Monte Carlo to show the importance of lateral interactions in the appearance of the CO-TPD-profile. The inclusion of lateral interactions results in the appearance of a new maximum in the simulated CO-TPD profile if modeled using the mean-field, quasi-chemical approach or kinetic Monte Carlo. It is argued that α2-CO may thus originate from lateral interactions rather than a differently bound CO on Fe(100). A detailed sensitivity analysis of the effect of the strength of the lateral interactions between the species involved (CO, C, and O), and the choice of the transition state, which affects the activation energy for CO dissociation, and the energy barrier for diffusion on the CO-TPD profile is presented.

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The valorization of CO 2 appeals to the chemical industry due to the reduction in greenhouse gas emissions and the ability to offer more renewable products. Propylene production is the second largest process in the chemical industry, and it strongly depends on fossil fuel feedstocks. Coupling CO 2 reduction with propane dehydrogenation boosts conversion and produces CO, a valuable platform chemical currently synthesized by fossil-methane reforming. In this work, (i) we demonstrate the environmental benefits of coupling CO 2 with a life-cycle assessment under industrial conditions, potentially reducing emissions by 3 t CO2-eq per ton of propylene produced. (ii) We screen supported catalytic materials�both known and novel�with a focus on propane and CO 2 reaction mechanisms under industrial reaction conditions of 400−700 °C and pressures of 1−6 barg (redox: V,

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Nico Fischer opened a general discussion of the paper by Nora de Leeuw: You have chosen Cu as a potential catalytic material and your calculations show that Cu is not the ideal surface to decompose hydrazine to H2. Which materials would you be looking into in the future? Have you found any design parameters that should be followed? Nora de Leeuw replied: We have made in-depth studies of three diff erent mechanisms for N2H4 decomposition and these could be followed up using other potential catalysts, for example including Ir and Cu alloys.Katherine Holt asked: In your model you neglect lateral adsorbate-adsorbate interactions. How can these be incorporated into the model and how would this in uence the results? Nora de Leeuw answered: We could incorporate lateral interactions by ana-lysing the coverage eff ect. However, we have already reported previously that the interaction between species is insigni cant at less than 0.01 eV, except for N2H4 + CH2, which is explicitly included in the microkinetic simulations.Michael Bowker remarked: In Table 1 (DOI: 10.1039/C6FD00186F) there appear to be no net barriers in the adsorption-desorption processes from the gas phase. For example, dissociative adsorption of hydrogen (step R7) and desorption (step R6) have exactly the same energetics. It is known that this reaction is highly net activated from the gas phase, with very low sticking probabilities, 1 and hence the forward and reverse barriers are very diff erent. This will have a signi cant eff ect on H populations on the surface and on H2 production rates.