Ceramics-Silikáty 59 (2) 125-134 (2015)

SORPTION OF CESIUM USING KZnFc ON PHOSPHORIC ACID-BASED GEOPOLYMER

The adsorbent was synthesized from the acid-base reaction between metal ferrocyanide and acidic phosphate at room temperature. The metal ferrocyanide granular inorganic adsorbent based on phosphate geopolymer for the removal of cesium in either batch or packed-bed operation has been developed in this study. In this work, the compressive strength of granular inorganic adsorbent was investigated under different liquid-to-solid, metal ferrocyanide-to-geopolymer and MgO-to-KH₂PO₄ ratios. The result showed that the compressive strength of the adsorbent increased with the increase of MgO-to-KH₂PO₄ ratio. It was found that the optimization of metal ferrocyanide-to-geopolymer and MgO-to-KH₂PO₄ ratios was important in improving both the compressive strength and the adsorption capacity of the adsorbent. The metal ferrocyanide granular inorganic adsorbent prepared were characterized by analysis such as XRD, TGA, FTIR and SEM spectra. In this study, the synthesized granular inorganic adsorbent has demonstrated a Cs removal efficiency of over 99 % and an adsorption capacity of 1.7-1.8 meq·g^-1 in simulation wastewater containing 2000 ppm Cs under adsorbent dose of 0.0067 g·ml^-1.

Keywords: Metal ferrocyanide, Granular, Compressive strength, Phosphate geopolymer