Metal-organic framework-mediated synthesis (MOFMS): catalysts for methane oxidation to oxygenated products

Abstract

Methane is the major components of natural gas. However, it is extremely inert, which limits their application in syntheses. Today, this compound is mainly employed as fossil fuels or converted to olefins, aromatic hydrocarbons, or oxygenated compounds via energy-demanding processes. Therefore, implementing greener technologies to ensure that methanol is efficiently used will be essential in the future. In this scenario, developing new catalysts that can convert methane to products like alcohol, aldehydes, ketones, and carboxylic acids is a challenge to modern chemistry. Several materials have been developed for this purpose, but they still have limitations and are expensive. Despite the small number of studies involving Metal-Organic Frameworks (MOFs) as catalysts for the oxidation of light alkanes, MOFs based on transition metals are expected to be the future for these reactions. Nevertheless, their low thermal stability is an issue. Instead of MOFs, here we propose the use of metal carbides, which present the structural versatility of MOFs, but are more thermally stable. We will perform metal-organic framework-mediated synthesis (MOFMS) to obtain metal carbides and mixed-metal carbides with well-dispersed, chemically and thermally resistant metals, which is desirable for a catalyst that will be subjected to different conditions of temperature and pressure. More specifically, Cu, Fe, and mixed-metal carbides will be synthesized and employed to catalyze the conversion of methane to oxygenated products. To this end, MOFs will be synthesized by solvothermal methods and submitted to pyrolysis or calcination, to obtain metal nanoparticles in a porous carbon matrix. The resulting materials will be characterized and later tested in a batch and flow reactor to establish the most efficient catalyst. (AU)