キレート樹脂によるＥＰ灰溶出液からのホウ素・セレンの除去

Abstract

The removals of boron, selenium (IV) and selenium (VI) in a solution of coal fly ash from a power plant (EP ash) were examined using chelating resin (Diaion CRB02, Mistubishi Chem.). Boron, Se (IV) and Se (VI) were removed quantitatively in the pH range 4-7 using the resin. At optimum pHs, the maximum adsorbed quantities were 11.7mg&middotg-1 for boron, 9.7mg&middotg-1 for Se (IV) and 6.8mg·g-1 for Se (VI). The adsorbed elements were recovered quantitatively, yielding 98% for boron, 98% for Se (IV) and 88% for Se (VI) with a 1M sulfuric acid solution whose volume is 10times the resin volume. When a solution of EP ash (boron : 2.7mg·l-1, selenium : 0.06mg·l-1, sulfate ion : 89.7mg·l-1), whose volume is 500times the resin volume, was passed through the column at the space velocity of 30h-1, breakthrough points did not appear by this volume of the sample solution. Thsese results suggest that boron, Se (IV) and Se (VI) in the solution of EP ash can be recovered successfully using the resin.