The problem

Three factors are dramatically affecting international energy markets: the rise of China and India as major global economic powers, the continued growth in United States energy demand, and instability in key oil-exporting regions. When combined with the increasing impact of climate change and the subsequent policy focus on boosting renewable energy options as well as achieving greater energy efficiency within the scope of existing infrastructure, it is clear that the energy ‘status quo’ is untenable in the long-term.

At the same time, absent necessary investment or regulatory reform (a price on carbon), the renewables sector will struggle to achieve the economies of scale required to supersede fossil fuel sources of energy. Ultimately, a solution to the present situation will demand a multi-faceted scientific and policy response.

The idea

An award-winning 17-year old chemistry student from India, Raghavendra Ramachanderan has developed a chemical reaction that de-oxygenates alcohols using sunlight as an energy source. In layman’s terms, this means that it is possible to reuse half-burnt fuel using sunlight as a catalyst. 

The project works on the concept of photoredox catalysis. A photocatalyst is a substance that absorbs light. Ramachanderan has developed specific photocatalysts that absorb light of the visible wavelength, and have been modified to have a few specific physical properties. Upon absorbing light, they become excited and can give away electrons to molecules nearby that have a reduction potential close to the oxidation potential of the photocatalyst. The catalyst can then regain the electron from a sacrificial electron donor. 

This pathway is exploited such that alcohols are converted to an intermediate by the reaction conditions, accepting the electron from the photocatalyst and degrading into the alkane. In short, a photocatalyst converts an alcohol to the alkane by the energy that it receives from sunlight. 

Oxygenated compounds form the intermediates during the burning of fuel. Most of the energy is released in this situation because of their conversion to alcoholic compounds. According to principles of engineering, they can be isolated; they have not been to date because there has been no purpose. But, if these compounds are isolated, then they can be converted to their de-oxygenated versions - that is, back into fuel. Fuel can be burnt, energy obtained, and then converted back to fuel using a sunlight-triggered reaction.

Potential impact

Though in its very early stages, the Visible Light De-oxygenation project has significant potential to alter the way in which fuel is consumed. By suggesting the possibility of recycling the fuel we as a society already consume for further use, Ramachanderan’s research could allow both individuals and industry to achieve greater efficiency from the fuel sources already at our disposal. 

Moreover, because the key advance is the utilization of sunlight as a catalyst, the Visible Light De-oxygenation project fits within the scope of organic or ‘green’ chemistry, avoiding the release of further pollutants into the environment. The reaction is absolutely ecofriendly and also near-quantitative yields have been obtained. The project addresses crucial questions, therefore, as well as potentially offering one element of a solution to the global energy crisis.

Social value

As noted, the Visible Light De-oxgenation project fits within a wider ‘green chemistry’ movement committed to identifying products and processes that reduce the prevalence of hazardous substances in everyday life. The public exposure that would come with a scale-up of Ramachanderan’s research - especially when combined with his profile as a young, talented scientific mind - would provide social value in broadening further the debate around energy efficiency, and demonstrate that the notion of ‘renewable’ energy can also be applied to existing energy sources.