Methane Decomposition: Production of Hydrogen and Carbon Filaments
نویسنده
چکیده
Hydrogen, presently, finds application as a chemical rather than a fuel in commercial operations. However, being a non-polluting source of energy, hydrogen is predicted to be the ‘‘fuel of the future’’. One of the most potential applications for hydrogen is to power fuel cells. Major automobile manufacturers are currently working towards developing fuel cell vehicles; such vehicles are expected to significantly curtail the pollution from the transportation sector. Fuel cells, because of their modular nature, can be utilized to provide heat and electricity not only to single homes but also to provide a large amount of electricity to a large grid network. Fuel cells can be broadly classified into two types; high temperature fuel cells such as molten carbonate fuel cells (MCFCs) and solid oxide polymer fuel cells (SOFCs), which operate at temperatures above 923 K and low temperature fuel cells such as proton exchange membrane fuel cells (PEMs), alkaline fuel cells (AFCs) and phosphoric acid fuel cells (PAFCs), which operate at temperatures lower than 523 K. Because of their higher operating temperatures, MCFCs and SOFCs have a high tolerance for commonly encountered impurities such as CO and CO2 (COx). However, the high temperatures also impose problems in their maintenance and operation and thus, increase the difficulty in their effective utilization in vehicular and small-scale applications. Hence, a major part of the research has been directed towards low temperature fuel cells. The low temperature fuel cells unfortunately, have a very low tolerance for impurities such as COx; PAFCs can tolerate up to 2% CO, PEMs only a few ppm, whereas the AFCs have a stringent (ppm level) CO2 tolerance. Methane, due to its abundance and high H/C ratio (highest among all hydrocarbons) is an obvious source for hydrogen. Steam reforming of methane represents the current trend for hydrogen production. Other popular methods
منابع مشابه
Catalytic Decomposition of Methane and Ethylene into the Carbon and Hydrogen
The role of nickel as catalyst on the conversion of methane and ethylene in a gas phase flow reactor in the absence of oxygen is studied. In this study, nickel in its different forms is used as catalyst. The role of pressure, flow rate, and temperature on the conversion of feed gases is investigated. The experiments have been carried out in the presence and absence of the catalysts to measure t...
متن کاملCO x Free Hydrogen Production by Catalytic Decomposition of Methane Over Porous Ni/Al2O3 Catalysts
متن کامل
Ordered mesoporous carbons as highly active catalysts for hydrogen production by CH(4) decomposition.
Ordered mesoporous carbons have been applied, for the first time, as catalysts for hydrogen production via methane decomposition, showing higher and more stable activity than commercial carbonaceous catalysts.
متن کاملStepwise methane steam reforming: a route to CO-free hydrogen
A method for the production of clean hydrogen is demonstrated. The process consists of two steps involving the decomposition of methane to CO-free hydrogen and surface carbon in the first step followed by steam gasification of this surface carbon in the second step. This process can be operated in cycles and could be an excellent hydrogen source for fuel cells and other devices or processes req...
متن کاملSimulation and modeling of hydrogen production from glucose biomass model compound via hydro-thermal gasification
Glucose is a 6-carbon carbohydrate compound present in plants and the ingredient for hemicellulose which makes up 30% of plants’ total mass. The current study uses glucose as reactant and evaluates hydrogen generation at different temperatures and different amounts of input flow of glucose – water mixture. Hydrothermal gasification method is used for hydrogen generation in an open system with c...
متن کاملCO-Free Production of Hydrogen via StepwiseSteam Reforming of Methane
CO-free hydrogen is produced by the reversible cyclic stepwise steam reforming of methane for use in fuel cells and other processes that are sensitive to CO poisoning. The process consists of two steps involving the decomposition of methane in a first step followed by steam gasification of the surface carbon in a second step. The ease of carbon removal in step II is strongly dependent on temper...
متن کامل