ION-EXCHANGE PROPERTIES OF HARDENED GEOPOLYMER PASTE PREPARED FROM FLY ASH

概要

論文の詳細を見る
We prepared a hardened geopolymer paste by treating a mixture of fly ash and alkali silicate solution at 80℃ for eight hours. X-ray diffraction and ^<29>Si-NMR spectra indicated that the hardened geopolymer paste was amorphous with a zeolite-like structure. Cation exchange examination indicated that its exchange capacity was 150-170, 200-230, and 250-300meq/100g against alkali/H_2O ratios of 0.10, 0.15 and 0.20, respectively. The ion selectivity of the hardened geopolymer paste follows the order of Pb>Ba>Sr>K>Na. Except in the case of Cr-adsorption (which causes structural change), the selectivity of divalent ions is greater than that of monovalent ions, and ion selectivity increases in the order of ascending atomic number for the identical valence.