Carbon dioxide emitted when hydrocarbons are combusted with atmospheric oxygen that presents in the air. A simple fuel as methane contains one carbon atom in it is structure. It produces 275 kg of carbon dioxide when 1 kg of methane is burned completely similarly, gasoline has an average of 8 carbon atom and it produces 309 kg of carbon dioxide per 1 kg of gasoline. Diesel has 12 carbon atoms on average and it emits 311 kg of CO2 per 1 kg of diesel. Fuel oil has 25 carbon atoms this give out 312 kg of carbon dioxide per 1 kg of it. This is lots of carbon dioxide accumulating in the air. Our planet cannot survive if carbon dioxide is generated continuously at present rates. Carbon capture is one best solution for this problem.
Solid fuel, coal also has one carbon atom in its molecular structure and it gives 367 kg of carbon dioxide for 1 kg of coal burned completely in the presence of air. The above calculations are a simple material balance that gives an idea how much carbon dioxide is left in the air during the combustion process. We generate day-by-day vast amount of carbon dioxide into the Earth’s atmosphere. However, a simple carbon capture technology is that by recycling carbon dioxide into liquid fuel will help in preventing fossil fuel consumption for automobile and vehicles.
Important techniques used for carbon capture:
- Clathrate Hydrates
- Membrane separation
- Cryogenic separation
- Gas-expanded liquids
What can we do with captured carbon dioxide?
We have the technique of capturing the CO2. Now we need a solution to use it without harming the environment. One of the ideas was using it to make recycle fuel and other was using it for forestation. With less energy, CO2 converted to fuel by the help of microorganisms. Using solar energy algae consumes carbon dioxide and produce biomass.
Another technique is by electrocatalysis and with photoelectrochemical methods, the CO2 converted to methanol and its derivatives.
Carbon Capture Technology to convert CO2 to CH3OH/ DME:
Carbon dioxide can be converted into methanol and as well as to the fuel which can be used in diesel engines as dimethyl ether is the objective of the technology. If automobile fuel produced with this technology then most of, the carbon dioxide issue will be resolved because a major part of carbon emission is from vehicles only. In addition, this technology directly applied to the industries furnaces that generate carbon dioxide as flue gas. The flue gas containing carbon dioxide and carbon monoxide directly sent into the electrochemical section to converts CO2 to CH3OH and then CH3OCH3.
Carbon capture by gas expanding liquid formation:
The energy needed to turn carbon dioxide gas into a liquid is more than its gas-expanded liquid form. Organic liquids pressurised with carbon dioxide gas and form a CO2 expanded solvent. This technique produces a unique form of phase that contains gas dispersed in a liquid in stable form.