Breaking Bread
Story: Rob Biertempfel | Photography: Liz Palmer
Inspiration for scientific innovation can be found in unlikely places. At a cookout with some buddies about five years ago, Dr. Adam Wood, an assistant professor of engineering, came up with what he believes is a better way to desalinate saltwater when he tossed a hamburger bun into the bonfire.
“I threw it right into the middle of the fire, where there is little oxygen for combustion but there’s still intense heat,” Dr. Wood recalled. “Right before my eyes, boom, that piece of bread turned into a carbon electrode.”
A carbon electrode conducts electricity under certain conditions. When two electrodes are connected to a battery, one becomes positively charged and the other negatively charged. Add some low-salinity water, and the electrodes will attract the positive and negative ions—removing the salt and other minerals and leaving fresh water. The process is called capacitive desalination (CDI).
When doing CDI on a broad scale, the electrodes can be the most expensive part. Dr. Wood, who back then was a graduate student at Carnegie Mellon University, was searching for a way to make it cheaper and more accessible. He needed to create electrodes out of something that is high in carbon content, plentiful, and inexpensive.
Dr. Wood had been conducting trials with mangrove root but was looking for a more sustainable raw material. As he looked at the chunk of bread-turned-charcoal in the heart of that bonfire, Dr. Wood realized he’d finally found a great ingredient for his carbon electrodes: bread.
“Bread is one of the most wasted foods in the world,” Dr. Wood said. “It’s very high in carbon content, and very easy to get.” However, Dr. Wood’s research with bread came to a halt when the COVID-19 pandemic shut down everything. “I never stepped foot in the research lab again at CMU and ended up coming to Saint Vincent [to teach],” he said. Aided by his SVC students, Dr. Wood recently resumed working on the project.
Dr. Wood’s research might someday revolutionize how people around the world get their drinking water. The most common method of desalination is reverse osmosis, in which water is forced at high pressures through semi-permeable membranes that act as microscopic strainers to remove salt and other impurities. CDI has the potential to get the job done at a lower cost.
“We thought, this is great—but maybe we can we make it even better,” Dr. Wood explained. “We wondered if we could fine-tune the shape and produce an electrode with kind of the surface features we want.”
David Bujdos, C’24, of Munhall, who last spring graduated with a Bachelor of Science in engineering with concentrations in mechanical and materials engineering, made huge strides with the research over the past two years. “He took my method and basically said, ‘I have a better method,’ and he ran with it,” Dr. Wood said. “He’s an all-star student.”
David Bujdos and Dr. Adam Wood review data from their desalination research.
To create the electrodes, store-bought bread is heated in furnace tubes in the lab. Any type of bread would work, but, for consistency’s sake, Dr. Wood and Bujdos exclusively use Pepperidge Farm whole wheat. “My job was to come up with different ways to create the electrodes and control their shape,” Bujdos explained. Bujdos first tried stamping custom surface topologies onto the bread, sort of like making thumbprint cookies on a microscopic scale. Then he devised a better process—mashing the bread into a paste which then goes onto molds to form ridges and valleys.
In May, Saint Vincent College was awarded a $200,000 grant from the National Science Foundation for Dr. Wood’s desalination/water disinfection project. A significant portion of the grant funded undergraduate students who worked on the project over the summer of 2024 and into following academic year.
Bujdos wrote a paper on his work and submitted it to a journal for peer-reviewed publication—quite an advanced step for an undergraduate. “People usually don’t do that until the second year of their PhD [program],” Dr. Wood remarked.
This fall, Bujdos began working toward his PhD in the materials science and engineering program at the University of Pennsylvania. He remains keenly interested in CDI’s potential. “What motivated me throughout this whole process is that everything is a recycled material,” Bujdos said. “Bread, water, and a solar cell from the dollar store is pretty much all it takes.”