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Stable catalyst design for the activation of methane to syngas, hydrogen, and chemicals


    Problem Statement

    Methane and light alkanes are species with relatively poor economic interest. Our goal is to activate C–H σ-bond to produce hydrogen, olefins, carbon monoxide, and carbon nanofibers, following different process strategies such as oxidative coupling (for olefins), CO2 dry reforming (for syngas), cracking or catalytic decomposition (for hydrogen-free of COx and sequestrated carbon nanotubes/nanofibers), cracking/co-cracking with CO or methanol. We work on developing, synthesizing, characterizing, and testing innovative catalysts with a twist of reaction engineering concepts, with a focus on multi-scale implications.

    We delve into the mechanistic insights into a series of in-house-synthesized metal-supported heterogeneous catalysts by combining them with dynamic reactors and ab initio calculations. We explore catalysts with extended lifetimes, enhanced activity, selectivity, and heat transfer. These catalysts are based on alloys-intermetallics, high entropy alloys, exsolved perovskites, and SiC, among others.

    We investigate novel reactor designs based on forced-dynamic, operando, and fluidized-bed reactors to amplify kinetic information and improve selectivity.

    CHA2023

    Goals

    • Develop a microkinetic-based modeling framework to analyze the catalyst performance
    • Scale the technical catalyst for its application in demanding exothermic (oxidative coupling of methane using SiC and spray drying) or fluidized-bed (catalytic decomposition of methane) conditions
    • Develop new catalytic concepts based on Ni-alloys (Ni-Fe, -Co, -Zn…)
    • Improve the catalyst structure-function correlations using in-situ, operando, and dynamic techniques and reactors

    Related People

    Related Publications

    Activation of n-pentane while prolonging HZSM-5 catalyst lifetime during its combined reaction with methanol or dimethyl ether

    by Cordero-Lanzac, Martinez, Aguayo, Castaño, Bilbao, Corma
    Catal. Today Year: 2022 DOI: https://doi.org/10.1016/j.cattod.2020.09.015

    Abstract

    This work explores the synergies during combined reactions of n-pentane (nC5) with oxygenates (methanol or dimethyl ether, OX). The experimental runs have been carried out in a packed bed reactor at 500 °C, using a high silica HZSM-5 zeolite-based catalyst with different oxygenate-to-n-pentane (OX/nC5) ratios in the feed. A significant enhancement of the n-pentane conversion occurs for low OX/nC5ratios in the feed (0.1−0.25), especially when using dimethyl ether (DME). In addition, the presence of n-pentane reduces the rate of catalyst deactivation by coking during the conversion of oxygenates. These results have been explained on the grounds of a mechanistic interaction between the reactants: (1) the fast formation of methoxy and olefin intermediates from oxygenates, particularly from DME, could explain the promotion of n-pentane cracking, by facilitating the activation of the alkane by hydrogen transfer reactions; (2) the attenuation of deactivation during the conversion of oxygenates could be related to a lower extent of the arene cycle in the dual-cycle mechanism (limiting the polymethylbenzene formation). The analyses of used catalysts by means of temperature-programmed oxidation and confocal fluorescence microscopy have pointed out the higher reactivity of DME than that of methanol also for yielding coke structures.

    Keywords

    O2H CHA