Researchers Explore Use of Rare Earth Inhibitors in Preventing Corrosion

A research team consisting of a chemistry professor and four PhD students from James Cook University (JCU) (North Queensland, Australia) are launching an investigation into the anticorrosive properties of rare earth inhibitors. The aim of the investigation led by JCU Professor of Chemistry James Cook is to prevent corrosion in steel infrastructure assets such as bridges, water cooling towers, and oil and gas pipelines.

Cook and the four JCU PhD students will receive a $420,000 grant from the Australian Research Council Discovery Project (Canberra, Australia).

According to Junk, global costs of corrosion to infrastructure totals about $4 trillion USD. This cost is a problem, he says, because it impacts the safety and durability of vital infrastructure assets that provide essential services around the world.

Moreover, Junk points out that corrosion failures will become more prevalent due to environmental changes brought on by climate change, including rising temperatures, higher sea levels, greater aerosol generation, and increased CO₂ levels.

With that in mind, Junk and his team are focusing on rare earth inhibitors, which many researchers regard as a promising option due to their proven anti-corrosion properties. They are also seen as a more environmentally friendly alternative to chromate ion, a corrosion inhibitor for aluminum, zinc, and certain other metals.

“It’s common to use chemical inhibitors to reduce corrosion’s impact and chromate salts have been excellent at this for over 80 years,” says Junk. “But the toxic nature of the chromate ion is well known and for almost 30 years research has focused on finding a more effective and environmentally acceptable replacement.”

The JCU team will research the use of rare earth inhibitors, which include 17 relatively common chemical elements dispersed around the Earth’s crust. Junk believes that developing a range of rare earth inhibitors would enable Australia to utilize its reserve of rare earth resources, as well as help satisfy the global demand for corrosion inhibitors.

“We’re going to make a comprehensive examination of the nature and function of the protective film formed by rare earth inhibitors on steel surfaces,” says Junk. “Then we’re going to make improved inhibitors in the expectation that we will get a better product out of it both in terms of environmental sustainability and in the practical effect of protecting material.”

“Our aims are at the cutting edge of corrosion science and our methods and equipment will be too,” he adds. “We’ll be taking the advantage of the unique capabilities of atom probe tomography in probing both structural and chemical features of metal surfaces at nano and atomic levels for the first time.”