COLLEGE PARK, Md. – Engineers at the University of Maryland have developed a new use for wood: filtering water. Liangbing Hu, leader of the project and professor of materials science at the University, and his colleagues added nanoparticles to wood, and then used it to filter toxic dyes from water.

Hu and his team of engineers began with a block of linden wood soaked in palladium – a metal used in catalytic converters in cars to remove pollutants from the exhaust. The palladium bonds to particles of dye.

Hu says the wood’s natural channels, that once moved water and nutrients between the leaves and roots, allowed the water to flow past the nanoparticles for efficient removal of the toxic dye particles. The water, tinted with methylene blue, slowly dripped through the wood and came out clear.

"This could be used in areas where wastewater contains toxic dye particles," said Amy Gong, a materials science graduate student, and co-first author of the research paper.

The purpose of the study was to confirm whether wood could be used to remove impurities from water. The researchers did not compare the filter to other types of filters.

"We are currently working on using a wood filter to remove heavy metals, such as lead and copper, from water,' said Hu. "We are also interested in scaling up the technology for real industry applications."

"We found that the wood’s channels are actually slightly bent, and they are connected by pores, which slightly increase the time that the water is in contact with the wood," said Siddhartha Das, professor of mechanical engineering.

The research, which was published March 31, 2017, in the journal ACS Nano, is the latest innovative use of wood by the UMD team. Their previous work includes making a battery and a supercapacitor out of wood,  along with transparent wood used in windows.

Source: University of Maryland