Carbon dioxide (CO2) is recognised as the primary contributor to climate change, representing a global emergency. The transition to renewable energy will ensure the elimination of CO2 emissions from energy-intensive activities such as power generation and transportation. Nevertheless, this won’t be sufficient to reduce its concentration in the atmosphere. This is because there are processes that emit carbon dioxide not from the use of fossil fuels but from the process itself. 

In addition, we are witnessing an increase in the frequency of natural disasters, especially forest fires, which emit massive amounts of carbon that have been stored for thousands of years. These vast emissions cannot be balanced through the planet's natural absorption of carbon dioxide. Therefore, different strategies must be developed and adopted simultaneously to tackle CO2 emissions. These strategies should work in parallel with the transition to renewable energy and the development of carbon-free or low-carbon technologies.

The International Energy Agency has considered carbon capture, utilisation and storage (CCUS) as one of the four pillars of the global energy transition, along with electricity based on renewable energy, bioenergy and hydrogen, estimating that the reduction of nearly half of global emissions could come from carbon capture and use technologies.

CCUS can address emissions in sectors with limited other options, such as manufacturing cement, steel, and chemicals and producing synthetic fuels for long-distance transportation. This technology can remove carbon dioxide from the atmosphere, and it is the only option to reduce its concentration, as it has reached approximately 0.042%, which is considered high. The value before the Industrial Revolution was lower than 0.03 %.

In the research centre on Carbon Dioxide Capture and Utilisation (CCDCU) at Sunway University, studies are carried out on CO2 capture agents derived from natural resources such as amino acids and converting waste materials into solvents or solid sorbents. This will help to develop low-cost and sustainable CO2 capture processes in the long run. The studies have shown on a laboratory scale that plastic waste can be converted into a solvent to capture carbon dioxide with efficiencies similar to current standard solvents.

The captured CO2 has many direct usages, such as in the “EOR” enhanced oil recovery projects, where the captured carbon dioxide is re-injected into depleted oil fields to extract more oil. Additionally, it can be used as a pH-adjusting agent in industries such as the sugar industry. Carbon dioxide can also be used as a carbon source in biotechnology to grow algae, and it has medicinal uses. Furthermore, supercritical CO2 is a powerful solvent in a process called supercritical fluid extraction (SFE), where it can be used to extract bioactive chemicals.

More importantly, carbon dioxide can be converted into value-added chemicals. For example, it can be reduced to carbon monoxide “CO” (CO), which can be combined with green hydrogen to form what we call syngas, which in turn can be converted into fuel, as well as intermediate chemicals such as ethanol and methane, and carbon dioxide can also be converted into carbonates such as calcium carbonate that has multiple industrial uses.

Carbon capture, Utilisation and Storage are crucial when battling the climate crisis. Sunway University’s CCDCU research centre will continue to contribute to the existing research on this topic as part of the effort to save our planet.
 

Professor Mohamed Kheireddine Aroua
School of Engineering and Technology
Email: @email