The term “rare earth element” (REE) is somewhat misleading — those 17 squares at the bottom of the periodic table appear fairly plentifully in the earth’s crust. But that doesn’t mean they’re easy to get to. They tend to be widely dispersed and appear in low concentrations, usually in hard-to-separate combinations with other elements.

That factor — the difficulty of collecting and separating significant amounts of the elements — presents a particular challenge to technology-heavy industries. REE are used in everything from cancer treatments to smartphones to nuclear reactor shielding, and the U.S. uses about 20,000 tons of them every year. Of those 20,000 tons, about 19,000 is imported from China. This puts the U.S. at an economic and a national-security disadvantage. Relying on the export policies of a foreign power for the materials needed to build missile guidance systems leaves the country at risk. But the U.S. has the potential to produce twice as much REE as it consumes — if it can separate them from the minerals in which they’re trapped.

Engineers at Southern Research (SR) have been identifying economically viable REE resources and exploring ways to free the REE from those resources. One crucial part of that effort is being able to accurately measure the REE at every phase of the process. Assessing the potential value of a given resource requires knowing how much REE it contains. Developing new technology to recover the REE requires knowing how much elements is present at each step to assess its efficiency. All of it demands accurate measurement of a wide range of REE, in chemically complex resources, in solid, liquid and gas form — which is made even more challenging by the fact that REE have similar chemical properties and are hard to differentiate and measure individually.

Using an industry-leading Agilent 8800 Triple Quad ICP-MS (inductively coupled plasma mass spectrometer), SR is able to measure the tiniest concentrations of these elements. SR modified an existing method for solid sample preparation to efficiently extract REE from more complex samples like coal fly ash. A combination of highly sensitive instrumentation and hard-earned expertise allow engineers to minimize interferences. With the modified sample preparation procedure and our advanced analytical capabilities to remove interferences, SR is able to consistently and accurately measure REE in any number of resources.

Developing a technique to extract and analyze REE from domestic sources could have a major effect on the U.S. economy. It has the potential to change the economic profile of key industries and create a domestic market — and even an export market — for these very valuable elements. “If we can economically extract these rare earth elements, the U.S. wouldn’t have to rely on other countries,” said Nishil Mohammed, Ph.D., a research engineer at SR. “The U.S. could be a source of rare earth elements for the future.”

As well-known as radium is for its harmful effects — the Radium Girls might come to mind — the idea of widespread water contamination can be a scary one. But it’s a reality, albeit generally at levels below those likely to cause cancer and birth defects. A recent analysis by the Environmental Working Group found that 170 million people in all 50 states are getting their water from a source contaminated with detectable levels of radium. Some exceeded public health guidelines, and in 27 states, water supplies were found to exceed legal limits.

Radium 226 and 228 are naturally occurring elements, but they naturally occur harmlessly deep underground. It’s usually the extraction of energy resources, particularly uranium mining, oil drilling and hydraulic fracturing (fracking), that brings them to the surface. Fracking, which now accounts of half of U.S. oil production and two-thirds of natural gas production, generates both valuable resources like oil or gas and less-welcome output like contaminated wastewater. Producing one gallon of raw crude oil, for example, generates eight gallons of wastewater on average. Fracking produces wastewater that brings up that naturally occurring radium and can lead to contamination of our water systems with harmful substances.

While technology is being explored that could treat contaminated wastewater at the mining site, development and implementation of that technology remains in the future. Until then, detecting and monitoring radium in the water system is the only way to protect the public from the dangers of contamination. Water samples have to be tested for radium in its numerous forms and oxidation states to determine the most effective remediation technique. And once the affected water has been treated and discharged back into the greater water source, that source has to be tested again to make sure nothing is accumulating.

The traditional approach to measuring radium contamination relies on alpha spectrometry, which is time consuming, labor intensive and slow to produce results. And the detection limits of traditional methods are greater than health-based limits, meaning that water analysis can show zero radioactivity even when radioactive elements are present at unsafe levels.

Southern Research (SR) uses a proprietary method coupling HPLC (high-performance liquid chromatography) with an Agilent 8800 Triple Quad ICP-MS (inductively coupled plasma mass spectrometry) for faster, more accurate measurement. Large water samples are passed through a column to isolate the contaminant for testing, and a combination of highly sensitive, leading-edge instrumentation and expertise honed over the course of a decade allow us to quantify and speciate even trace levels of radium. With the benefit of precise, accurate data, our clients are able to determine the best treatment solution for their water source, and then return for further analysis after treatment to ensure that efforts were successful.

SR has been offering state-of-the-art environmental analytical services to commercial and government clients since 2008. But we also are at the forefront of water-efficient, energy-efficient, cost-efficient technology for energy production. “We have experts on the energy side and the water side,” said Young Chul Choi, Ph.D., associate director of SR’s Industrial Water Practice. “We’re one of the few entities that maintains expertise in both energy consumption and water quality — the smallest amount of water you can contaminate when producing energy, and the smallest amount of energy you can expend on producing clean water. It goes back and forth, and we’re interested in both aspects.”

It can be hard to worry about contamination by a substance that regularly shows up in children’s vitamins. But selenium pollution via industrial waste can impair our waterways. The margin between “essential” and “toxic” levels of selenium is very slim, and even in small concentrations, selenium pollution is shown to have serious effects on fish and wildlife. In 2016, EPA recommendations under the Clean Air Act extended criteria to include selenium contamination in the food web, not just the water column, and future regulations could be even more stringent. Industrial and manufacturing facilities will need to treat wastewater streams for selenium prior to discharge, which means operators will be required to monitor selenium concentration to comply with regulations.

This is neither a simple nor an easy enterprise. It’s made particularly challenging by the fact that selenium comes in numerous different organic and inorganic species, and selection of remediation techniques and technology will vary depending on the species present. There is no simple “selenium pollution” — a water source could be contaminated with hydrogen selenide or selenium(IV), and that distinction is an important one when it comes to treating the contamination.

Speciated selenium measurement is a complex process requiring a combination of specialty instrumentation and human expertise. One issue of concern during the speciation process is the presence of interferences within the sample — threatening accuracy in measuring total selenium, even before any attempts at speciation take place.

“Selenium has different isotopes, which we monitor using ICP-MS (inductively coupled plasma mass spectrometry),” said Chaoyang Huang, an engineer and senior chemist at Southern Research. “Each species is subject to different polyatomic interferences from the water matrix. These are hard to isolate without a collision/reaction cell.”

Southern Research (SR) was the first lab in the Southeast to break into speciated selenium measurement and has been offering it as a service to commercial clients since 2008. The past decade has given us numerous opportunities to invest in the people and technology necessary to perform it well. Our proprietary method couples HPLC (high-performance liquid chromatography) with an industry-leading Agilent 8800 Triple Quad ICP-MS to speciate and quantify even trace levels of selenium in contaminated water.

That past decade has also given us an opportunity to develop an expertise around the wastewater itself.

“Because we understand the wastewater matrix, SR can proactively minimize the impact of interferences on the final analysis results,” Huang said.

State-of-the-art quality control measures allow us to ensure accuracy in both the total selenium and the speciated selenium measurement so SR’s clients can understand the nature of the selenium contamination and select effective treatment solutions.

Treating selenium contamination is important both for the health of the environment and for the health of facilities facing government regulation and potential penalties. Selenium speciation is the first step in knowing what to treat and how to treat it. Partnered with an experienced, market-proven lab, heavy industry and wastewater treatment facilities can keep waterways fresh and regulators satisfied.