반응표면분석법을 이용한 Hydroxyapatite 첨가 활성탄에서의 Cd 흡착특성에 관한 연구

Abstract

Cadmium (Cd) adsorption onto the activated carbon containing hydroxyapatite (HAP) was investigated in batch experiments and response surface methodology (RSM) using the Box-Behnken methods were applied to the experimental results. Cd adsorption with different HAP mass ratio of from 10% to 30%. With more HAP, Cd was more adsorbed. These results suggest that the higher HAP mass causes an increase of the ion exchange potential of the HAP sorbent. Equilibrium experimental results from Cd adsorption was fitted to Langmuir and Freundlich isotherm models. Cd adsorption on HAP sorbent were found to follow the Freundlich isotherm model well in the initial adsorbate concentration range. Also, Cd adsorption was a function of the HAP mass ratio (x1), initial Cd concentration (x2), and initial pH (x3) from the application of the RSM. Statistical results showed the order of significance of the independent variables to be initial Cd concentration > HAP mass ratio > initial pH.