News from Nanotechjapan

合成・材料

Cellulose nanofiber backboned Prussian blue nanoparticles as water-insoluble adsorbents for the selective elimination of radioactive cesium

 On November 14, 2016, the University of Tokyo announced that a collaborative research group led by Professor Bunshi Fugetsu has succeeded in developing cellulose nanofiber (CNF) backboned Prussian blue (PB, Ferric hexacyanoferrate) nanoparticles as powerful adsorbents for the selective elimination of radioactive cesium (Cs).  Details were published in Scientific Reports *.

 On March 11, 2011, due to the Tohoku earthquake and Tsunami, a huge amount of radionuclides had dispersed from the Fukushima nuclear reactors. Decontamination of the dispersed radionuclides from seawater and soil has been the topmost challenge. PB has been known as the most powerful material for selectively trapping the radioactive Cs, however,  its high tendency to form stable colloids in water has made PB to be ineffective for the open-field radioactive Cs decontamination because of spillage of water containing Cs loaded PB.

 The research group has solved this difficulty of PB by a nano combinatorial approach; CNF were used to immobilize PB via the creation of CNF-backboned PB (CNF/PB). CNF/PB was found to be insoluble in water, and it gave a 139 mg/g capability and a million (106) order of magnitude distribution coefficient for absorbing of the radioactive Cs ion.

 Field studies on soil and seawater decontaminations in Fukushima gave satisfactory results, demonstrating high capabilities of CNF/PB for practical applications.

* Adavan Kiliyankil Vipin, Bunshi Fugetsu, Ichiro Sakata, Akira Isogai, Morinobu Endo, Mingda Li, and Mildred S. Dresselhaus, "Cellulose nanofiber backboned Prussian blue nanoparticles as powerful adsorbents for the selective elimination of radioactive cesium", Scientific Reports, Vol. 6, Article number: 37009 (2016), doi: 10.1038/srep37009; Published online: 15 November 2016