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

Problem statement

Methane and light alkanes are surplus species and by-products 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, looking at multi-scale implications.

We delve into the mechanistic insights of a series of in-house synthesized metal-supported heterogeneous catalysts by combining them with dynamic reactors and ab initio calculations. We explore catalysts with promoted lifetime, activity, selectivity, and heat exchange.

We investigate novel reactor designs grounded on forced dynamic (operando) fluidized-bed reactors at high pressures to amplify the kinetic information and hydrogen.

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
CHA2023

Related People

Xueqin Bai (Bruce)

Related Publications

Engineering Thermally Resistant Catalytic Particles for Oxidative Coupling of Methane Using Spray-Drying and Incorporating SiC

by Lezcano, Velisoju, Kulkarni, Ramirez, Castaño
Ind. Eng. Chem. Res. Year: 2021

Abstract

Oxidative coupling of methane (OCM) is a promising single-step route to convert natural gas to high-valued chemicals. It is generally agreed that Mn–Na–W catalysts offer a balanced conversion–selectivity trade-off. The present work outlines a novel SiC–SiO2 support synthesized by spray drying to extend the lifetime of the catalyst. Incorporating SiC into the support enables the exothermic reaction heat to be effectively dissipated, avoiding hotspots and thermal shocks, and increasing the thermal resistance. The spray drying technique yields particles with a consistent distribution of SiC inside the particles, amplifying the thermal resistance of the catalyst. Our kinetic results show that the spray dried catalyst with SiC has significantly higher stability at high C2selectivity compared to the benchmark SiO2-supported catalyst prepared by wetness impregnation. This result is due to (1) the more uniform distribution of active phases and SiC provided by the spray drying methodology and (2) the greater thermal resistance provided by SiC, which avoids thermal shocking and stabilizes the Mn–Na–W phases during the long-term (70 h) stability test for OCM.

Keywords

CHA HCE