Direct carbon fuel cell
Encyclopedia
A Direct Carbon Fuel Cell (DCFC) is a fuel cell
that uses a carbon rich material as a fuel. The cell produces energy by combining carbon and oxygen, which releases carbon dioxide as a by-product.
The total reaction of the cell is C + O2 → CO2.
The process in half cell notation:
Despite this release of carbon dioxide, the direct carbon fuel cell is more environmentally friendly than traditional carbon burning techniques. Due to its higher efficiency, it requires less carbon to produce the same amount of energy. Utilized carbon can be in the form of coal
, coke
, char
, or a non-fossilized source of carbon.
At least four types of DCFC exist:
Fuel cell
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...
that uses a carbon rich material as a fuel. The cell produces energy by combining carbon and oxygen, which releases carbon dioxide as a by-product.
The total reaction of the cell is C + O2 → CO2.
The process in half cell notation:
- Anode: C + 2 O2- → CO2 + 4 e-
- Cathode: O2 + 4 e- → 2 O2-
Despite this release of carbon dioxide, the direct carbon fuel cell is more environmentally friendly than traditional carbon burning techniques. Due to its higher efficiency, it requires less carbon to produce the same amount of energy. Utilized carbon can be in the form of coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
, coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...
, char
Char
Char is the solid material that remains after light gases and tar coal tar have been driven out or released from a carbonaceous material during the initial stage of combustion, which is known as carbonization, charring, devolatilization or pyrolysis.Further stages of efficient combustion are...
, or a non-fossilized source of carbon.
At least four types of DCFC exist:
- The first one is based on the Solid oxide fuel cell (SOFC) concept.
- The second one is molten hydroxides fuel cell. William W. Jacques obtained an US Patent 555,511 in this type of fuel cell in 1896.
- The third one is based on the Molten Carbonate Fuel Cell (MCFC) concept. William W. Jacques obtained a Canadian patent in this type of fuel cell in 1897.
- The fourth is a molten tin anode solid oxide fuel cell design, which utilizes molten tin and tin oxide as an inter stage reaction between oxidation of the carbon dissolving in the anode and reduction of oxygen at the solid oxide cathode.