Fuel cells are widely recognized as being promising alternative energy devices. Generally, fuel cells generate clean electric power quietly and without directly combusting fuels. Fuel cells operate by converting chemical energy (such as from O2 and H2) into electricity in a relatively efficient manner. For example, proton exchange membrane (PEM) fuel cells are considered to be approximately 40% efficient, phosphoric acid fuel cells (PAFCs) are considered to be approximately 45% efficient and molten carbonate fuel cells (MCFCs) and solid oxide fuel cells (SOFCs) are considered to be between approximately 40% to 80% efficient depending on their specific configurations. The greater the efficiency of a fuel cell, the greater conservation of energy, as well as the lower the emissions of CO2.
Considerable efforts have been expended to develop and manufacture fuel cells as alternative power sources for a variety of products. For example, fuel cells have been developed for use in automotive applications. Additionally, efforts have been made to develop fuel cells to replace batteries for a variety of electronic devices, including cell phones and laptop computers.
Many fuel cells, such as PEM fuel cells, operate using a process that requires hydrogen. Hydrogen may be produced in a variety of ways including, for example, electrolysis, high temperature electrolysis, thermochemical, or through reforming processes. Considerable efforts have been made to improve the production of hydrogen. In many cases, it becomes desirable to produce hydrogen on site or “on-demand” rather than having to require bulk storage of hydrogen.
Reforming is a process used to produce hydrogen gas from hydrocarbons using an appropriate catalyst. For example, one type of reforming is known as steam-methane reforming (SMR). In the SMR process, methane reacts with steam on a nickel catalyst to produce hydrogen and carbon monoxide (also known as synthesis gas or “syngas”) according to the following chemical equation:CH4+H2O→CO+3H2 
The SMR process is conventionally carried out at temperatures of approximately 850° C. and at pressure levels of approximately 1 to 2 megaPascals (MPa). The SMR process is endothermic and conventionally uses an external source of hot gas to heat tubes in which the catalytic reaction takes place.
Another reforming process is known as autothermal reforming (ATR). In one form, the ATR process uses oxygen and carbon dioxide in a reaction with methane to form hydrogen and carbon monoxide according to the following chemical equation:2CH4+O2+CO2→3H2+3CO+H2O+Heat
In another form, the ATR process uses oxygen and steam in a reaction with methane according to the following chemical equation:2CH4+O2+H2O→5H2→3CO+2CO
Yet another reforming process is known as partial oxidation that produces syngas according to the following chemical reaction:CH4+H2O→2H2+CO
It is desirable within the industry to continually improve hydrogen production processes including the various reforming processes. It is also desirable within the industry to improve the apparatuses, systems and methods associated with the production of hydrogen such as may be used with fuel cells and other devices.
USPTO Backgrounds
USPTO Backgrounds