Adsorption of Fluoride on Lanthanum or Cerium Modified Mesoporous Alumina

Nowadays, a kind of highly efficient fluoride adsorbent has that employ La, Ce as the modifier to the surface of certain carriers has aroused wide concerns. However, the loading of La and Ce into mesoporous alumina(MA) is rarely reported. In this study, La and Ce modified mesoporous alumina were prepared they were used for the removal of fluorine. The structural properties of the adsorbent were characterized by N2 desorption isotherm, X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR). Furthermore, the effects of contact time, initial concentration and pH value on the adsorption of fluoride were investigated. The results showed that the adsorption equilibrium had been achieved at 150 min, with the fluorine removal rate of 92.2%(La/MA). The order of fluorine adsorption capacity was La/MA>Ce/MA>MA. The fluorine adsorption capacity increased with the increase of initial concentration. Satisfactory fluorine removal effect could be acquired under the pH value of 5-9. The adsorption isotherm equation was in accordance with the Langmuir adsorption isotherm model. The La/MA exhibited a maximum adsorption capacity of 27.9 mg/g. The degree of influence of co-existing anions on fluoride removal followed the order of CO32->SO42->NO3->Cl-. Finally, by comparing the FTIR before and after adsorption, it could be seen that La/MA exerted the best effect on fluoride removal. © 2019, Materials Review Magazine. All right reserved.