To mitigate climate change, giving up the use of fossil carbon is of utmost importance. One of the approaches is the reuse of carbon dioxide. With the help of emission-free electricity, almost all organic chemicals and polymers, such as plastics, can be produced from carbon dioxide. There is considerable potential in their commercialisation.
"By reusing carbon dioxide, we could reduce our global reliance on fossil hydrocarbons without intensifying climate change. This enables a climate-neutral approach to producing fuels, chemicals, materials and food, which is also increasingly valued by the business world", says VTT's Research Professor Juha Lehtonen.
In an economy based on the reuse of carbon, fossil carbon is left in the ground while aboveground carbon, the carbon accumulated in the atmosphere and plants, circulates captured in different products: fuels, chemicals, materials and food. Forests act as both carbon sinks and an important source of renewable carbon. In addition to this, carbon can be captured and utilized from industrial emissions and, as technology advances, eventually from the air, too.
"It can be envisioned that, in the future, there will be more low carbon electricity and almost unlimited amount of atmospheric CO2 available. The biggest barrier to using CO2 are mainly the high production costs related to the supply of low-carbon energy in a world used to low-cost oil. Political decision-makers would now need to make bold decisions relating to low-carbon energy in any case", says Technology Manager Antti Arasto from VTT.
Carbon capture and utilisation will be one of the most important tools in helping to achieve the climate change mitigation targets determined by the Paris Climate Agreement.
Materials, chemicals, food and fuels from carbon dioxide
With the help of emission-free electricity, almost all organic chemicals and polymers currently manufactured from fossil hydrocarbons can be produced from carbon dioxide. Compared to fuels, the commercialisation of materials and chemicals may be easier due to their higher price level. Even though the production volumes of chemicals do not rise to the same level as those of fuels, a production method based on CO2 and electricity may reduce the need of forest biomass as feedstock for renewable chemicals.
It is already possible to make food protein from CO2 and emission-free electricity. When, in the future, part of the food needed by humankind will be made in bioreactors, field area will be freed for other uses. VTT has been developing a manufacturing method for proteins based on CO2 and emission-free electricity. It is currently being piloted by the start-up Solar Foods.
Two approaches to converting carbon dioxide
CO2 can be converted into different compounds using biotechnical and chemical conversion approaches. Biotechnical routes for CO2 conversion offer potential for higher value products, such as food ingredients, whereas chemical routes are efficient for bulk products, such as fuels and base chemicals. By utilising CO2 for chemicals and materials, it is possible to keep carbon within a cycle for longer compared to fuels.
In its new publication The carbon reuse economy – Transforming CO2 from a pollutant into a resource, VTT is presenting its view on how carbon can be turned from a pollutant into a resource with a favourable impact on climate change: https://www.vtt.fi/Documents/uutiset/2019/190620_FINAL_WEB_VTT_CRE_Discussion_Paper_PAGES_display.pdf