IIT Researchers Make Bacteria Eat Carbon Dioxide, Methane For Cleaner Fuel

Waste to wealth and combating climate change, a win-win laboratory scale solution has been developed by scientists at the Indian Institute of Technology Guwahati. They have deployed a bacteria to help them achieve this.

Professor Debasish Das and Dr Krishna Kalyani Sahoo of the Department of Biosciences and Bioengineering, IIT Guwahati, have developed an advanced biological method to convert methane and carbon dioxide into cleaner biofuels using a special type of bacteria called methanotrophic (methane-eating)  bacteria.

"A nifty biological sequestration route is the discovery but is still at five litre laboratory scale," said Mr Das. "This innovative approach represents a significant leap toward sustainable energy solutions and climate change mitigation."

The study addresses two pressing global challenges - the harmful environmental impact of greenhouse gases, and the depletion of fossil fuel reserves.

Methane, a greenhouse gas that is 27-30 times more potent than carbon dioxide, is a significant contributor to global warming. While turning methane and carbon dioxide into liquid fuels can reduce emissions and provide renewable energy, existing chemical methods are energy-intensive, expensive, and produce toxic byproducts, limiting their scalability.

"This research is a breakthrough as it demonstrates that biomethanol derived from bacteria feeding on methane and carbon dioxide can be a viable alternative to fossil fuels," professor Das said.

"Unlike conventional biofuels that rely on crops and create competition with food production, our method uses greenhouse gases, avoiding the food versus fuel issue. It is an environmentally and economically viable solution, using inexpensive resources while contributing to emissions reduction," he said.

The laboratory of professor Debasish Das, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IIT Guwahati)

The IIT Guwahati team has developed a fully biological process that uses a soil-borne friendly microbe named 'Methylosinus Trichosporium', a type of methane-eating bacteria, to convert methane and carbon dioxide into biomethanol under special conditions.

Unlike traditional chemical methods, this process eliminates the need for expensive catalysts, avoids toxic byproducts, and operates in a more energy-efficient manner.

The innovative two-stage process involves capturing methane to generate bacteria-based biomass and using the biomass to convert carbon dioxide into methanol.

Professor Das and his team subsequently took it forward and the biomethanol produced in their laboratory was blended with normal diesel and tested in a four-stroke diesel engine.

It showed up to 87 per cent reduction in carbon monoxide, hydrocarbons, hydrogen sulphide, and smoke emissions, and improved efficiency since the diesel-methanol blends outperformed pure diesel in fuel consumption, energy efficiency, and engine performance while maintaining similar mechanical efficiency.

The biological conversion of methane and carbon dioxide into biomethanol not only provides a cleaner fuel alternative, but also has industrial applications as a precursor for producing chemicals like formaldehyde and acetic acid.

Professor Das said this process offers immense potential to decarbonise critical industries, including oil and gas, refineries, and chemical manufacturing, paving the way for a more sustainable future.