A new method for extracting carbon dioxide directly from air and converting it to oxygen and nano scale fibers, made of carbon, could pave way to an inexpensive technique to make valuable building materials and may even serve as a weapon against climate change.
Carbon fibers are increasingly being used as a structural material in aerospace, automotive and other industries, owing to their strength and light weight. The useful attributes of carbon fibers also include electrical conductivity enhanced at the Nano scale level.
The carbon fiber composites eventually replace steel, aluminum, and even concrete as a building material. The problem is that it is very expensive to make carbon fibers and also only much lesser Nano fibers can be obtained.
Solar Thermal Electrochemical Photo (STEP) Carbon Capture Process
This process makes use of infrared sunlight as well as visible light to generate the large amount of heat needed to run the desired reaction.
The process requires molten lithium carbonate with another compound lithium oxide, dissolved in it. The lithium oxide combines with carbon dioxide in the air, forming more lithium carbonate.
When voltage is applied across two electrodes immersed in the molten carbonate, the resulting reaction produces oxygen, carbon (which deposits on one of the electrodes) and lithium oxide, which can be used to capture more carbon dioxide and start the process again.
The different nano fiber shapes and diameters can be achieved by adjusting specific growth conditions such as,
- The amount of current applied at specific points of time &
- The composition of the various ingredients used in the process.
They also showed they could make very uniform fibers.
As for the technology’s emissions-cutting potential, the researchers are optimistic. They calculate that given an area less than 10 percent of the size of the Sahara Desert, the method could remove enough carbon dioxide to make global atmospheric levels return to preindustrial levels within 10 years, even if we keep emitting the greenhouse gas at a high rate during that period. Of course, this would require a huge increase in demand for carbon nano fibers.
Properties of Carbon Fiber:
- High Strength to weight ratio
- Brittle in nature
- Corrosion resistive
- More Electrical Conductive in nature
- Fatigue Resistance is high
- Fire Resistance (Can be used to make protective clothing for firefighters)
- High Thermal Conductivity
- Low coefficient of thermal expansion
- Non poisonous
- Biologically inert
- Excellent EMI (Electromagnetic Interference)
- Shielding Property
Simple and cost-effective way of making a high-value product.
It’s also a means of storing and sequestering carbon dioxide in a useful manner, a stable manner, and in a compact manner.
If the process is powered by renewable energy, the result is a net removal of carbon dioxide from the atmosphere.
One of the other strengths of the method is the small amount of energy required to power it.
Products going to be developed:
Works are now going on to produce high- yield carbon nano fibers from atmospheric CO2. Such nano fibers are used to make strong carbon composites, such as those used in the Boeing Dreamliner, as well as in high end sports equipment, wind turbine blades and a host of other products.
D.Lakshmi Priya (12BTT022)