TITLE:
Preparation of Iron Ferrocyanide-Supported Nanofiber Membrane for Purification of Cesium-Contaminated Water
AUTHORS:
Yasuhito Mukai, Ayana Mizuno
KEYWORDS:
Nanofiber Membrane; Iron Ferrocyanide; Cesium; Adsorption
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.4,
March
25,
2014
ABSTRACT: The
earthquake in northeastern Japan that occurred on March 11, 2011 brought about
the nuclear accident, resulting in the detection of radioactive cesium in soil
and water over a wide region around Fukusihma. In this study, with the aim of
the establishment of an effective method for removing cesium from water
contaminated with cesium, the functionalized membrane with large cesium
adsorption capacity per unit mass was prepared by combining nanofibers having a
large specific surface area with iron ferrocyanide having a high selectivity
for cesium adsorption. The nanofiber membrane made of polyacrylonitrile (PAN)
was used as a base material of the functionalized membrane. Nanofiber membranes
were immersed in the dispersions of iron ferrocyanide with various
concentrations and pH values. After taking it out, it was dried at various
temperatures and then non-immobilized iron ferrocyanide was completely removed
through cleaning. As a result of the evaluation of completed affinity
membranes, the amount of iron ferrocyanide immobilized by the nanofiber
membrane increased significantly with the increase in the iron ferrocyanide
concentration but subsequently showed a tendency to decrease rapidly, resulting
in a distinct maximum at the iron ferrocyanide concentration of 3 wt%. And, the
supported amount of iron ferrocyanide to the nanofiber membrane increased as pH
became lower. Moreover, it was found that as high temperature as possible
without exceeding the glass transition temperature of PAN was optimal as a
drying temperature of prepared affinity membrane.