Uranium from sea water: Bhabha Atomic Research Centre develops special membrane to extract uranium
2011 By Syed Akbar Visakhapatnam, Feb 22: Bhabha Atomic Research Centre has developed a specialised membranethat could extract uranium from seawater much faster than the conventional methods,boosting uranium mining from the Deep. Seawater is estimated to contain as much as 4.6 billion tons of uranium and the nuclearfuel obtained from the oceans could help feed nuclear reactors once the conventionaluranium reserves of 5.5 million tons are exhausted. With a vast coastline, India canextract large resources of sea uranium to meet its uranium demand. Laboratory studies in Barc have shown that the new membrane called PEGMP has increasedthe overall efficacy for uranium uptake from seawater. This is far superior to theconventional membrane called PAO. Since it has been proved that the uranium obtained fromthe seawater can be used in uranium reactors for power generation, nuclear scientistshope that the Barc’s new membrane combined with nanotechnology will make seawater uraniummining highly economical. According to Dr Ashok K Pandey or radiochemistry division of Barc, “PEGMP membrane offersseveral advantages over widely used PAO membrane for uranium recovery from seawater. Anattempt was made in our lab to carry out comparative evaluation of PEGMP-membrane withPAO-membrane for uranium sorption under seawater condition. The studies indicatedpotential applications of the PEGMP-membrane in uranium preconcentration from seawaterand other natural aquifers for uranium quantification as well as its recovery,” he said. Dr Ashok is presenting a technical paper at the ongoing five-day 10th biennial symposiumon nuclear and radiochemistry (Nucor – 2011) in the port city of Visakhapatnam. “Thepresence of uranium in the dissolved state makes its recovery from seawater possible. Theuniform concentration of uranium throughout the sea indicates existence of a dynamicequilibrium between dissolved uranium and insoluble sedimentary uranium. Therefore, therecovery of uranium from seawater may lead to dissolution of uranium present in theseabed,” he pointed out. However, the economical recovery of uranium is a challenge in view of the chemical andbio-aggressive nature of seawater. Stating that the scientific challenge is thedevelopment of the sorbents that are selective towards uranium and can withstand hostilebio-chemical marine environment over a prolonged period, he said efforts are on in makingthe recovered uranium cost competitive. Enormous volume of water has to be processed for recovery of one ton of uranium. Barc’s new membrane technology is also superior to other conventional processes involvingsolvent extraction, ion exchange, reverse osmosis and ultra filtration.