Ion sensors could reduce toxic waste emitted from mines

A Minnesota startup company has licensed sensor technology developed at the University of Minnesota that could help prevent toxic byproducts of mining from ending up in the environment.

Chemistry associate professor Philippe Buhlmann in the university’s college of science and engineering developed the ion selective electrode (ISE) sensor. Startup United Science will now complete the design and commercialise the technology, which is already being tested in the mining industry.

ISE sensors are used to detect and measure a specific ion in complex chemical solutions used in mining, food safety and health sciences. They can be used in caustic, high-pressure environments such as mining, as well as applications in food safety.

Miners often use toxic chemical reagents to draw out valuable ores during the mining process, but often use more than necessary to ensure all the ore is extracted. By detecting and measuring the concentration of such chemicals, the sensor would allows miners to use less of them, resulting in less toxic material in the waste stream.

According to United Science, if implemented industry-wide the sensors could eliminate at least 24 tons of toxic waste emissions per mine. While the company is currently focusing on copper mines, the technology may be extended to iron mines.

’In mining applications they can use exactly the necessary amount of chemical reagent. If you add too little, you’re going to lose a lot of money, because you are not separating the metal out of the ore. If you’re using too much, you’re wasting money and the agent ends up in the environment,’ said Buhlmann.

Buhlmann’s research was funded by the National Science Foundation (NSF) and the National Institutes of Health (NIH). Recently, Buhlmann and Jon Thompson, the CEO of United Science, received Small Business Technology Transfer (STTR) grants from NSF to commercialise the technology.