Recent Advances in the Catalytic Conversion of Methane to Methanol: From the Challenges of Traditional Catalysts to the Use of Nanomaterials and Metal-Organic Frameworks

Abstract

Methane and carbon dioxide are the main contributors to global warming, with the methane effect being 25 times more powerful than carbon dioxide. Although the sources of methane are diverse, it is a very volatile and explosive gas. One way to store the energy content of methane is through its conversion to methanol. Methanol is a liquid under ambient conditions, easy to transport, and, apart from its use as an energy source, it is a chemical platform that can serve as a starting material for the production of various higher-value products. Accordingly, the transformation of methane to methanol has been extensively studied in the literature, using traditional catalysts as different types of zeolites. However, in the last few years, a new generation of catalysts has emerged to carry out this transformation with higher conversion and selectivity, and more importantly, under mild temperature and pressure conditions. These new catalysts typically involve the use of a highly porous supporting material such as zeolite, or more recently, metal-organic frameworks (MOFs) and graphene, and metallic nanoparticles or a combination of different types of nanoparticles that are the core of the catalytic process. In this review, recent advances in the porous supports for nanoparticles used for methane oxidation to methanol under mild conditions are discussed.

Recent Advances in the Use of Controlled Nanocatalysts in Methane Conversion Reactions

“…The oxidative coupling of methane (OCM) process presents an opportunity to generate ethene (C 2 H 4 ), which holds significant value across various industrial sectors [50,101]. It serves as a vital monomer for polyethylene production and as a primary component in fuels such as gasoline (C 5 -C 10 ) or diesel (C 10 -C 20 ) [47,50,59,68].…”

“…Natural gas represents a significant resource for catalytic conversions aimed at transforming methane into valuable industrial inputs and energy sources like syngas and hydrogen [27,71,84]. Figures 5-8 illustrate several important catalytic reactions for converting methane into added-value products through cleaner and more renewable processes, including the steam reforming of methane using water, the dry reforming of methane using CO 2 , electrocatalysis, and photocatalysis, which utilize electricity and sunlight as activation sources [11,26,27,71,72,76,[84][85][86]94,101].…”

“…transforming methane into valuable industrial inputs and energy sources like syngas and hydrogen [27,71,84]. Figures 5-8 illustrate several important catalytic reactions for converting methane into added-value products through cleaner and more renewable processes, including the steam reforming of methane using water, the dry reforming of methane using CO2, electrocatalysis, and photocatalysis, which utilize electricity and sunlight as activation sources [11,26,27,71,72,76,[84][85][86]94,101]. The steam reforming of methane for hydrogen production, depicted in Figure 5, is a pivotal process, which involves methane reacting with water vapor over a catalyst to produce hydrogen gas and carbon monoxide.…”