The U.S. Department Of Energy Wants To Turn Coal Waste Into High Tech Components

Jul 25, 2017

Researchers at the National Energy Technology Laboratory south of Pittsburgh are discovering valuable rare earth elements in coal waste.

Rare earth elements are things like scandium, yttrium and neodymium. They’re essential to creating high tech goods such as cell phones, superconductors and lasers.

A Pennsylvania clay sample to be analyzed in the NETL lab.
Credit Liz Reid / 90.5 WESA

“'Rare earth elements' is actually a little bit of a misnomer,” said Tom Tarka, who runs NETL’s rare earth element program. “Rare earth elements aren’t necessarily rare. They exist everywhere in the world. Even if you’re digging your garden, you’re going to have rare earth elements.”

The elements are not necessarily more rare than other elements, but they are more dispersed which can make them difficult to mine.

Most of the rare earth elements in the world come from China. According to the U.S. Geological Survey, the United States imported $150 million worth of rare earth elements in 2015. But Tarka said coal and coal waste could become a domestic source.

Coal ash, the byproduct of burning coal, is one of the largest individual types of industrial waste in the U.S. In 2014, 130 million tons were created, and most of it was sent to landfills, dumped into waterways or stored in the ground.

Coal and coal waste samples are fired at extremely high temperatures to create discs which are then dissolved into a solution before analysis.
Credit Liz Reid / 90.5 WESA

“If we are able to bring down the price of rare earth elements domestically, we can also spur domestic industry and create more goods here and bring more manufacturing jobs here,” he said.

Tarka and his team are developing cutting edge technology for identifying 55 different elements all the way down to the parts-per-trillion level. Think of that as one square inch in a 250-square mile area.

It’s the same principle they used to figure out how to capture pollutants from burning coal, researcher Evan Granite said.

“We’re very excited, we’re almost ready to do a dance, because we’re taking our separation and characterization expertise that we’ve honed over the last 50-60 years in this lab targeting pollutants," Granite said. "Now we’re targeting valuable elements associated with the coal.”

Their work is still in the early research stages. Tarka said he expects an industry extracting rare earth elements from coal to spring up in the next five to 10 years.