Vigyan Yuva awardee Bappi Paul: Turning cabon dioxide directly into ethanol

Bappi Paul of National Forensic Sciences University won the award for developing a process to convert CO2 into alcohol and eliminate volatile organic compounds.

Bappi Paul, a nanotechnologist at the National Forensic Sciences University, Gandhinagar, is one of the winners of this year’s Vigyan Yuva Shanti Swarup Bhatnagar awards in the category of Environmental Science. He describes processes he has developed to convert carbon dioxide into alcohol and eliminate volatile organic compounds.

Bappi Paul is a nanotechnologist at the National Forensic Sciences University, Gandhinagar,

What I do

I am working on two projects: the direct hydrogenation of carbon dioxide to ethanol, and the total ultilisation of toluene, a volatile industrial compound.

Carbon dioxide is a harmful greenhouse gas linked to climate change, but the gas is also necessary for plant growth and various industrial processes. Unfortunately, this balance is being disrupted by higher emission compared to consumption, so the need is either to reduce the excess or to convert it into value-added chemicals. In our work, we convert carbon dioxide to the useful chemical ethanol.

Volatile organic compounds emitted by industry and transport vehicles too contribute majorly to global air pollution. Among these, toluene, benzene, formaldehyde, phenol, propylene, acetone, and styrene pose major concerns. In recent years, various methods have been developed for elimination these compounds. My work relies on catalytic oxidation of toulene, one of the most efficient approaches for the removal of volatile organic compounds because of its lower reaction temperature, better processing efficiency, less harmful pollutants, and the non-requirement of additional fuel.

For conversion of carbon dioxide to ethanol, industry currently relies on an indirect route that goes through a series of steps. The focus of my present work is on the thermocatalytic transformation of carbon dioxide directly to ethanol using a catalyst in presence of water and hydrogen. We have developed the catalyst by synthesising rhodium nanoparticles supported on nanostructured iron silica oxide. This is a single-step process in which we found that the water and the catalyst have an excellent synergistic effect for promoting the reaction. The process provides high selectivity and yield of ethanol.

Volatile organic compounds are carbon-based chemicals with boiling points between room temperature and 260°C. For their catalytic oxidation, the key is again the synthesis of a highly active catalyst. We have developed platinum nanoparticles supported on nanostructured tungsten oxide for low-temperature total oxidation of toluene. The process provides a single-step total oxidation of toluene to carbon dioxide and water over the catalyst at 164°C under atmospheric pressure, with excellent catalytic durability.