Reagent for preventing elution of radioactive cesium from incinerator fly ash

Abstract

A small amount of nickel hexacyanoferrate(II) was found to prevent the elution of radioactive cesium from incinerator fly ashes that were generated near Fukushima Daiich Reactors. The solution eluted from the wet fly ashes is highly alkaline containing large amounts of calcium,  sodium and pottasium chlorides, which makes it difficult to use well-known cesium absorbers such as zeolites and Prussian blue. Nickel hexacyanoferrate(II) acts as a very efficient cesium absorber under such conditiions. The amount of nickel hexacyanoferrate(II) necessary for preventing the elution is as low as a few tens of grams.