Researchers at Brown recently received a $1.75 million grant from the National Science Foundation's Centers for Chemical Innovation Program to study whether carbon dioxide can be used in place of fossil fuels in the production of industrial chemicals. The multidisciplinary, multi-institutional project involves researchers in both engineering and chemistry.
Millions of tons of industrial chemicals are produced each year that require petroleum for starting material, said Tayhas Palmore, professor of engineering, biology and medicine and principle investigator on the grant. Petroleum is a fossil fuel that, when burned, releases carbon dioxide - a greenhouse gas that has been linked to climate change - into the atmosphere. Given the growing demand for petroleum and diminishing quantities of it, devising a way to use carbon dioxide in its place during chemical production would reduce the carbon footprint of the production process.
Carbon dioxide is present in high concentrations in exhaust from factories and automobiles. The researchers hope that in the future, exhaust could be collected and used as the starting carbon dioxide source for industrial chemical production.
Palmore described using carbon dioxide as a "way to get around using oil, a limited resource that is only getting more expensive." In this way, researchers would be able to close the energy cycle and create a more sustainable means of chemical production.
Palmore's team is investigating how to convert carbon dioxide into "commodity chemicals" such as ethylene, acrylic acid and formic acid. These chemicals are created in bulk and then purchased by other companies to make pharmaceutical and plastic products. While the current production method requires petroleum-derived precursors, the new process would use emitted carbon dioxide as a starting material.
Currently, "there is no effective means of sequestering carbon dioxide and using it for a useful purpose," said Steven Ahn PhD'17, who is studying engineering.
But this is what the researchers hope to change.
Chemical catalysts can be used to convert carbon dioxide into these commodity chemicals, said Nilay Hazari, assistant professor of chemistry at Yale, a collaborator on the research. Catalysts reduce the minimum amount of required energy for a reaction, allowing the reaction to occur at a faster rate. When carbon dioxide and catalysts are combined, the reaction yields the desired chemical products. Through study of carbon dioxide catalysis, the researchers also hope to develop a catalyst that would be practical for use in the industry, Hazari said.
"The strategy should be competitive, if not better than what is currently commercially available," Hazari said.
Though the scale of chemical industry emissions is small relative to that of the automobile industry, pulling carbon dioxide out of the atmosphere and finding an alternative to petroleum starting material would be environmentally beneficial, Ahn said.
The process could also be applied to other areas, such as heating. "If we can make ethylene, we're on the way to figuring out how to make methane," Palmore said. "This applies to fuels, and fuels are used everywhere."
"It is possible that fundamental knowledge that we gain in this will be useful in a process for developing fuels from carbon dioxide," Hazari said. "And that would have an impact."
