Researchers find new way of removing metal from water

Throughout the summer, you could often find Ben Hewson ’19 sharing his notes with Professor Charley Liberko in the chemistry lab during the Cornell Summer Research Institute (CSRI).

They’re hoping that something that started out as a simple idea could turn into something much more.

“There’s this idea that wood is composed of these two polymers, cellulose and lignin,” Liberko said. “Most of the time we are taking the wood and getting rid of the lignin and keeping the cellulose. The cellulose is what we use for the paper. … Many times this huge amount of lignin, which is the second most abundant polymer on earth, just goes to waste. I had it in my mind, what can we do with lignin? What kind of things can we turn lignin into that might be useful for someone? As we thought about water and thought about getting rid of metal ions in water that might be contaminating things, I thought, well, lignin should be a perfect thing for that.”

That idea fell in line with Hewson’s plans for the future. He wants to be a doctor to help people, so now he’s exploring one aspect of that through the test tubes of the chemistry lab.

“I’m really excited about it especially since it’s a new project, and I get to pioneer it my own way,” Hewson said. “It feels really cool to be able to just explore and figure things out on my own, with help from Dr. Liberko. I feel good about it, knowing that this could potentially be something that’s really big and great.”

Here’s how it works. They heat up ordinary sawdust in an oven at 190 degrees Celsius to remove the cellulose. Then, the remaining lignin and the metal solution get mixed together.

“I’m working with iron, copper, nickel, and lead so far,” Hewson said.

The lignin acts as a sponge with the metal. Hewson pours the solution into a filter, which leaves behind water with the reduced amount of metal.

“In order to be able to test whether or not we are removing the metal ions, we have the instrumentation that will do that for us, but most people don’t have the instrumentation that we have here. So, we are developing tests for concentrations of different metal ions that rely on color,” Liberko said.

“All it takes is one drop of this potassium ferricyanide to create a color reaction,” Hewson added.

So far the duo has been able to remove up to 90 percent of metal ions in the water. They say this CSRI research is only the beginning of something that could make a big difference for people across the world and a big difference for this aspiring doctor.

“[During CSRI] I get to work in a lab on a campus that I’m comfortable with and with a professor that I know,” Hewson said. “I feel comfortable asking questions, learning, and even making mistakes and learning from those. I’m getting better in an environment that I’m completely comfortable with.”

This is just one example of the many research projects going on for CSRI, for others visit our website at cornellcollege.edu/research.