Scientists from the Desalination Division, Bhabha Atomic Research Centre (BARC) recovered uranium at milligram levels from sea water using electron beam grafted amidoxime. BARC and the Commissariat a’ Energie Atomique (CEA), France, are collaborating to develop three innovative and efficient methods of uranium extraction. The first method uses resin-grafted with calixarene (a synthetic material, indecently expensive.); magnetic separation is the second method and the third uses a canal system using absorbents.
They developed a semi pilot scale facility to produce radiation grafted sheets of 1 metre X 1 metre size. They collected about 800 microgrammes of uranium in five campaigns from CIRUS Jettyhead; about 1.8 milligrammes from the seawater intake and outfall canals at the Tarapur Atomic Power Station and around 200 microgrammes from Andaman and Nicobar Islands. Though these amounts are trivial, it gives confidence in the technology
Reviewing the Work in Japan
Dr Masao Tanada of the Japanese Atomic Energy Agency hopes to get funding to construct an under-water uranium farm covering nearly 400 square miles that would meet one-sixth of Japan’s annual uranium requirements.
Tanada asserts that Japan’s nuclear power industry can harvest the 8,000 tons it needs annually from the Kuroshio Current that flows along Japan’s eastern seaboard.
Japanese researchers found out that they can harvest uranium from sea by cultivating genetically engineered gulfweed which will grow in sea at an unbelievable rate of two metres an year. The weed selectively soaks up heavy metals including uranium.
What will you do with possibly the millions of tons of grass left over after recovering uranium? Convert it to bioethanol. Gulfweed is an ideal non-food source of bio-ethanol. Gulfweed traps carbondioxide from sea.
The Mitsubishi Research Institute (MRI) has recently recommended Japan mass-culture seaweed to collect natural resources such as bio-ethanol and uranium. In the “Apollo and Poseidon Initiative 2025,” MRI suggests that Japan cultures gulfweed, which can grow more than 2 metres high a year in the sea. The plants could also absorb carbon dioxide and purify the seawater, and can be used as non-food alternative energy sources for bio-ethanol. In April, MRI plans to inaugurate a consortium comprising public research institutes and manufacturers to move the plan forward. Using advanced molecular and gene-engineering technologies, MRI estimates that Japan would be capable of producing 65 million metric tons of gulfweed a year, and recovering a resource of 195 million tons of uranium. The annual rate of recovery is 40% of Japan’s total consumption. (19 February 2008, Nikkan Kogyo Shimbun)
Using polymers, the total amount of uranium recovered from three collection boxes containing 350 kg of fabric was >1 kg of yellowcake after 240 days of submersion in the ocean. So 65 million tons of seaweed might get 195,000 tons/year of uranium based on a comparable efficiency.
Dr Masao Tamada, of the Japan Atomic Energy Agency, has developed a fabric made primarily of irradiated polyethylene that is able to soak up the minute amounts of uranium – around 3.3 parts per billion – in the seawater.
Dr Tamada hopes to secure funding to construct an underwater uranium farm covering nearly 400 square miles that would meet one-sixth of Japan’s annual uranium requirements.
“Other countries are conducting similar research but none are as advanced as we are,” he said. “We need to conduct more development research and be able to produce the adsorbent material on a large scale, but we could achieve this within five years.”