Review and Outlook of Hydrogen Production through Catalytic Processes

Abstract

Hydrogen holds immense potential as a sustainable energy source as a result of its eco-friendliness and high energy density. Thus, hydrogen can solve the energy and environmental challenges. However, it is crucial to produce hydrogen using sustainable approaches in a cost-efficient manner. Currently, hydrogen can be produced by utilizing diverse feedstocks, such as natural gas, methane, ammonia, smaller organic molecules (methanol, ethanol, glycerol, and formic acid), biomass, and water. These feedstocks undergo conversion into hydrogen through different catalytic processes, including steam reforming, pyrolysis, catalytic decomposition, gasification, electrolysis, and photoassisted methods (photoelectrochemical, photocatalysis, and biophotolysis). Researchers have extensively explored various catalysts, including metals, alloys, oxides, non-oxides, carbon-based materials, and metal−organic frameworks, for these catalytic methods. The primary objectives have been to attain higher activity, selectivity, stability, and cost effectiveness in hydrogen generation. The efficacy of these catalytic processes is significantly dependent upon the performance of the catalysts, emphasizing the need for further research and development to create more efficient catalysts. However, during catalytic hydrogen production, gases like CO 2 , O 2 , CO, N 2 , etc. are produced alongside hydrogen. Separation techniques, such as pressure swing adsorption, metal hydride separation, and membrane separation, are employed to obtain high-purity hydrogen. Furthermore, a techno-economic analysis indicates that catalytic hydrogen production through steam reforming of natural gas/methane is currently viable and commercially successful. Photovoltaic electrolysis has been commercialized, but the cost of hydrogen production is still higher. Meanwhile, other photoassisted methods are in the development phase and hold the potential for future commercialization.

Smart Designs of Zeolite-Based Catalysts for Dry Reforming of Methane: A Review

“…Syngas as a mixture of CO and H 2 has been efficiently utilized as a fuel or converted into other products. In particular, after a downstream processing (such as membrane separation or Fischer–Tropsch synthesis), pure H 2 and other value-added products could be formed. − The reactions to generate syngas mainly include reforming of natural gases and tars. − Among the various natural gas and tar molecules, CH 4 is featured with the high content of hydrogen, easy production, and large abundance, widely used as the raw feed in reforming reactions (Figure ), like steam reforming of methane (SRM), − dry reforming of methane (DRM), − and partial oxidation of methane (POM). − Therein, the SRM process is an industrially mature process and featured with a H 2 -rich syngas production; the downstream purification step can also be reduced due to the simultaneous Water–Gas Shift Reaction. − As the main products, the H 2 -abundant fuel stream suits the polymer electrolyte membrane fuel cells, which are more efficient than combustion engines. But it requires high energy to generate steam, and the catalyst suffers from sulfur poisoning .…”

Pt/CB-Catalyzed Chemoselective Hydrogenation Using in situ-Generated Hydrogen by Microwave Mediated Dehydrogenation of Methylcyclohexane under Continuous-Flow Conditions

“…Hydrogen gas (H₂) is one of the most important and sustainable clean energy alternatives to fossil fuels because after the combustion of H₂, only H₂O is produced instead of greenhouse gases [1][2][3]. Owing to its usefulness and sustainability, H₂ is widely used as an energy source in fuel cells and holds promise for various applications as a carbon-free energy source [4][5][6][7][8].…”

Pt/CB-Catalyzed Chemoselective Hydrogenation Using In Situ-Generated Hydrogen by Microwave-Mediated Dehydrogenation of Methylcyclohexane under Continuous-Flow Conditions

“…Hydrogen gas (H 2 ) is one of the most important and sustainable clean energy alternatives to fossil fuels because, after the combustion of H 2 , only H 2 O is produced instead of gases with high global warming potential such as CO 2 [1][2][3]. Owing to its usefulness and sustainability, H 2 is widely used as an energy source in fuel cells and holds promise for various applications as a carbon-free energy source [4][5][6][7][8].…”