Toxic dye from water can be removed – with a filter made of wood

In the University of Maryland, engineers developed another way to use wood: By adding nanoparticles to wood, Liangbing Hu of the Energy Research Centre along with some colleagues managed to create a wood filter to separate toxic dyes from water. The research, first published in ACS Nano, is another innovative use of wood by the team, having previously improved batteries with wood.

The team first soaked a block of linden wood in palladium, a metal used in the catalytic converters found in cars to eliminate pollutants from the exhaust, and then used the wood as a filter. The palladium bonds to the dye particles, and the natural channels in the wood, which once allowed water and nutrients to move between the roots and leaves, enable the water to flow past the nanoparticles and efficiently remove the toxic dye particles. The water, first tainted with die, will slowly drip through the wood and come out clear.

“This could be used in areas where wastewater contains toxic dye particles,” Amy Gong, a materials science graduate student, said.

Analysing wood through an engineering lens was the purpose of the study. The research scientists, however, did not compare the filter to other types of filters as they wanted to prove that wood could be used to remove impurities from water.

“We are currently working on using a wood filter to remove heavy metals, such as lead and copper, from water,” Liangbing Hu, professor of materials science, and the lead researcher, said. “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,” Siddhartha Das, professor of mechanical engineering said. During the project, his team assisted Hu’s team in studying the flow of water through the wood.

 

Source: University of Maryland