As global tensions continue to disrupt fuel supply chains and India remains dependent on imports for nearly 60 per cent of its LPG needs, the search for a sustainable, homegrown alternative has never been more urgent. Rising to this challenge, scientists at BITS Pilani, Hyderabad Campus have unveiled a breakthrough technology that transforms carbon dioxide (CO2) — one of the biggest contributors to climate change — into dimethyl ether (DME), a clean-burning cooking fuel. Led by Prof Sounak Roy along with Prof Satyapaul A Singh and Prof BM Reddy, and supported by the Anusandhan National Research Foundation (ANRF), the team has developed a patent-protected, single-step process to synthesise DME directly from captured CO2. Bridging the gap between environmental responsibility and energy security, this innovation offers a compelling step forward in India’s journey towards self-reliance and cleaner fuel alternatives. CE interacts with Prof Sounak Roy to delve into his team’s groundbreaking research on converting carbon dioxide into clean cooking fuel and its potential to transform India’s energy landscape.
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What was the moment that made you believe that CO2 could be directly converted into a viable cooking fuel in a single step?
This is the work which we started some years before with funding from the Anusandhan National Research Foundation (ANRF). Our proposal stemmed from the idea that carbon dioxide is a greenhouse gas and we need to handle this. If you look at the present scenario, there is slightly more than 426 ppm of carbon dioxide, which all of us believe is the reason for global warming, glacier melting, and other related issues. Now, there are various possibilities to mitigate it. One technique is called Carbon Capture and Storage (CCS). But what we tried to do was go one step ahead and think about converting it into carbon capture and utilisation. So, it becomes a complete valorisation process where we have a twofold advantage. Greenhouse gas mitigation is significant, and while doing that, we can also generate energy. You might also have seen that NITI Aayog, according to Indian standards, has a plan of 20% dimethyl ether (DME) blending with domestic cooking gas. This intrigued us to think that if we could couple both problems, not only would we tackle greenhouse gas emissions, but also achieve Atmanirbhar India by generating an alternative energy source. Currently, more than 60 percent of LPG is imported. That was the origin of this idea.
At a time when India’s LPG supply is vulnerable to global conflicts, how quickly can this technology realistically be scaled for national use?
This is a very important question. What we have done so far is a lab-scale demonstration. The basic USP of the science here is that, in a single step, we can convert carbon dioxide into — not a substitute — but an additional component of LPG, which is dimethyl ether. We have already established the catalyst and the process. However, this remains a lab-scale demonstration. With suitable collaborations, we can take it to the pilot scale and then move toward commercialisation. But that will take some time. We have already filed a patent, and our research has been communicated to a scientific journal. The next step is scaling it up for commercialisation with appropriate agencies.
How does your one-step synthesis of dimethyl ether fundamentally differ from existing multi-step processes globally?
Globally, the process involves first converting carbon dioxide into methanol. Then, methanol undergoes dehydration to produce dimethyl ether. However, the catalyst we have developed is a composite formulation where, in a single step, although methanol forms as an intermediate, we directly convert carbon dioxide into dimethyl ether. This offers two advantages. One, it reduces engineering and technological requirements. Second, it improves economic feasibility, as the same catalyst handles both processes simultaneously.
What were the biggest scientific or engineering challenges you had to overcome to make this process efficient and scalable?
We are material scientists. Some team members come from chemistry backgrounds, others from chemical engineering. Our first focus was on formulating the catalyst, which was the most fundamental and challenging aspect. We needed to address the problem from the grassroots level. Existing catalysts are suited for multi-step processes, but a single-step process requires two simultaneous reactions — carbon dioxide hydrogenation to methanol and methanol dehydration to dimethyl ether. So, the formulation of the catalyst, along with its structure, surface properties, and morphology, were key aspects we worked on. Addressing these helped us achieve these results.
Could DME eventually replace LPG entirely, or is blending the more practical pathway for now?
It is more of a blending approach, not a complete replacement. If you consider a 14 kg LPG cylinder, a 20 percent DME blend is quite significant. This reduces dependency on imported LPG. So, blending is the practical pathway, and current policy supports up to 20 percent blending.
With the Bureau of Indian Standards allowing 20 percent DME blending, what could be the next regulatory hurdles?
From my perspective, there are no immediate regulatory concerns. It depends more on scientific understanding — whether we can increase blending beyond 20 percent. So, it is more of a scientific challenge than a bureaucratic one.
Is this technology viable for rural India, where affordability is crucial?
The technology is viable wherever LPG cylinders are used. However, carbon dioxide emissions are mostly concentrated in urban and industrial areas. So, CO2-to-DME conversion would happen at sources like thermal power plants or the steel sector. Once DME is produced, it can be bottled and distributed, including to rural areas.
If this technology succeeds at scale, what kind of future do you envision for India’s energy landscape?
I believe this would be a paradigm shift. If our current results translate to the commercial level, it will significantly reduce dependency on imports and move us toward self-reliance.