Laser chemistry for Eu recovery

Nakashima, Nobuaki*; Yokoyama, Keiichi  ; Yatsuhashi, Tomoyuki*; Sakota, Kenji*; Iwakura, Izumi*

Studies on photo-reduction of trivalent europium, Eu(III), is revisited by nanosecond lasers at various wavelengths with a Ti:Sapphire, excimer, and dye lasers. We measured the quantum yields, wavelength dependence, and power dependence. As a result, we found that the photo-reduction is induced by a two-photon absorption with a relatively high efficiency as to be observed directly with eyes. Also, the quantum yield of one-photon reduction at 308 nm was determined to be 0.6. These results indicate that highly efficient and selective separation techniques are possible for f-electron elements using multi-photon absorption process induced by laser light.