Burning fossil fuels and deforestations result in an increased concentration of CO2 in the atmosphere. This means that there is an excessive amount of unwanted carbon, which, among other health issues, is contributing to a climate change. The perfect solution would be to just stop polluting but as that is not going to happen we have to find ways to capture this atmospheric carbon.
Scientists from the University of York found an interesting way to capture this unwanted carbon. They used North Sea water and recycled scrap metal to create a technology, able to capture more than 850 million tonnes of unwanted carbon dioxide in the atmosphere. The goal was to create a method which would be easy and at the same time scalable to bigger proportions. It had to be environmentally sound and capture carbon dioxide in such a way that it would not cause problems in the future. The developed technology transforms excess carbon dioxide into dawsonite – a solid mineral, which is already naturally found in the Earth’s crust.
At first scientists found that graphite lined aluminium reactors are able to mineralize carbon dioxide. They wanted to create an energy efficient process that would not require harmful chemicals. They filled aluminium reactor with sea water and waste aluminium from trash. The reactor uses solar power to turn carbon dioxide into dawsonite. Then scientists calculated how scaled up the process can be. They found that this basic principle can mineralize 850 million tonnes of carbon dioxide every year – comparable to much more energy- hungry processes, employing harmful chemicals.
Other processes sometimes require using hydrogen to start the reaction. However, in this case hydrogen is not absorbed – it is actually emitted as a by-product of the reaction. Hydrogen is not polluting. In fact, it is a desirable resource, which is very important for the zero-emissions future. Several automotive manufacturers are trying to create reliable cars with hydrogen fuel-cells and some factories are already using hydrogen reactors to make their own energy. Now scientists will try to increase energy efficiency of this process and to find ways to capture and utilize this created hydrogen. However, even using the wasted aluminium is already a revolutionary idea.
Professor Michael North, one of the authors of the study, said: “Tens of millions of tonnes of waste aluminium are not recycled each year, so why not put this to better use to improve our environment? The aluminium in this process can also be replaced by iron, another product that goes to waste in the millions of tonnes.”
Reducing waste, producing hydrogen and combating climate change at the same time – when will we see this in full-scale? It seems like scientists still have some questions to answer, so we should be expecting to wait from several years to, possibly, a decade.
Source: University of York