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The goal of this study was to investigate the reaction mechanisms linked with the oxy-fuel combustion of ethanol (C 2 H 6 O). The oxidation of ethanol in O 2 /N 2 and O 2 /CO 2 environments was examined using reactive molecular dynamics in the temperature range from 2200 to 3000 K at constant density media and O 2 /fuel ratio equals to 0.5. The main reactions were examined to supply a description of the ethanol oxidation behavior, the main product distribution, and the corresponding time evolution behavior in the atomic scale. It has been noted that the oxidation of C 2 H 6 O was initiated mainly from the same routes in both environments generating the same main species. However, the key reaction pathways were different depending on the media. We noticed an increase of CO formation when N 2 was replaced by CO 2 molecules, increasing the net flux of the following reactions: by CO 2 + H → CO + OH and CO 2 + CHO → OCOH + CO. This work also studied the effect of increasing O 2 concentration (O 2 /fuel ratio equals to 0.5, 1.0, and 2.0) in O 2 /CO 2 combustion. During the simulations, high oxygenated and unstable species were detected such as carbonates and carboxyl radicals. The change of the O 2 /fuel ratio from 0.5 to 2.0 lead to an increase of CO 2 formation mainly from O 2 + OCOH → CO 2 + HO 2 and O 2 + CO → CO 2 + O reactions. In addition, the increase of O 2 concentration attenuated the effect of CO 2 and could increase the occurrence of reactions that lead to flame cessation.

The use of molecular simulation has been growing in engineering field moved not just by the advances on computational power but also on the availability of reliable software. One potential use of molecular simulation is related to the screening of materials for a specific application. The reliability of molecular simulation results depends on the trustworthiness of the force field used, what by engineering purposes should be as simple as possible. This work provides an evaluation of the potential accuracy cost of using simple generic force fields to predict the adsorption of CO2, CH4, N2 and their mixtures on MFI. We employed the GCMC technique for this investigation. Different models and force fields to describe adsorbates and adsorbent were tested. The force fields performances were estimated through comparison with available adsorption experimental data. Transferability was evaluated on the prediction of pure and mixtures adsorption on CHA, LTA and FER. The results showed that a simple force field presented similar performance when compared to a more sophisticated one.