“Extraction of Alumina from Fly Ash waste”: A research by Institute of Minerals and Materials Technology, India

A team of researchers from the Institute of Minerals and Materials Technology (IMMT), India affirms to have developed a technique for transforming fly ash waste into wealth. As per the research team’s claim, they have extracted commercially-useful minerals like alumina among others containing rare earth elements from the ash. The process also intends to solve the issues related to the disposal of fly ash.

According to the researchers, the main achievement was the extraction of alumina, which could be used for manufacturing of aluminium metal, and the rare earth elements.

Dr Sanjay Kali, Senior Principal Scientist in Hydro and Electrometallurgy Department of IMMT, said: “The team was researching the institute’s laboratories since 2016 in a phased manner. They had collaborated with National Aluminium Company (NALCO). For conducting laboratory tests, they had been procuring fly ash samples from Nalco’s thermal Plant in Angul. The researchers had also filed for patenting the process along with Nalco.”

He also added: “From 1,000 kg of fly ash, we can extract 55 kg of rare earth elements. Around 25% of the extracts are alumina, while 60 to 62% is impure quartz and calcium or sodium silicate.”

The process was tested in bench-scale at IMMT. But, the researchers are now trying to set up a pilot plant for greater extraction of rare earth elements.

“We need huge quantities of fly ash for extracting substantial amounts of the rare elements,” Senior Principal Scientist said.

The Minister of Coal, Govt. of India, Pralhad Joshi glorified the process on social media. Ashwini Vaishnaw, a Member of the Parliament also left a message on social media saying: “IMMT technology to harness rare earth elements and other minerals from fly ash. Coal India would be benefitted by it."

 The coal minister replied: “Sure is an interesting concept of waste to wealth. @CoalIndiaHQ should collaborate with IMMT, Bhubaneswar for harnessing minerals from fly ash.”