BENGALURU: Researchers at the Indian Institute of Science (IISc) are reportedly close to figuring out a way to convert carbon dioxide (CO2) into fuel substances, akin to methanol. They have developed a data-driven computational framework that would help scientists map nearly 10,000 chemical reactions involved in such a potential conversion of the gas into fuel, using a copper catalyst.
The data-driven approach could help scientists better understand and eventually design effective catalysts for turning the gas into chemicals and fuels. First, a database of 152 reactions was generated using quantum-mechanical simulations, and then machine learning models were trained to rapidly predict activation energy barriers.
Automation was applied to predict possible reactions involving 105 surface species, allowing the researchers to expand the original network to 9,389 elementary reactions.
“When we modelled the process using the 152 reactions considered initially, the network wrongly predicted formic acid, not methanol, as the major product, and underestimated how much CO2 gets converted.
Only when we expanded the network to include thousands of additional, previously overlooked reactions did the predictions fall in line with what we and others see experimentally,” said corresponding author Ananth Govind Rajan, an associate professor in the Department of Chemical Engineering at IISc.
The network of reactions was able to predict an approximately 40-fold increase in CO2 conversion, identifying Methanol and Carbon Monoxide as major products. The model validation was performed by scientists G Valavarasu and Santhosh Kotni at Hindustan Petroleum Corporation Limited’s (HPCL) Green Research and Development Centre, and by Amol Amrute and colleagues at the Agency for Science, Technology, and Research in Singapore.
“The idea that Hydrogen can transfer as an intact molecule, without first splitting into atoms, runs against what most of us were taught. This surfaced only because the network was large enough to allow for it, and the observation held up when we went back and computed those steps explicitly,” added co-author Shivam Chaturvedi, a doctoral student in the Department of Chemical Engineering, IISc.