摘要
A method was proposed for removing zirconium （Zr） from hydrous titanium dioxide （HTD） by the NaF solution. The effects of main parameters, i.e. pH values, NaF dosage, temperature and retention time, on the removal of zirconium were stud- ied. The optimal conditions were found as the following： pH value, 〈5.5; molar ratio of NaF to TiQ, 0.6; retention time, 80 min and temperature, 80℃. The removal rate of Zr under the optimized conditions was above 87.7%. The adsorption energy of the preferential absorption of hydrofluoric acid for Zr（OH）2SOt（OH2） on the （001） crystal surface of HTD was determined by theo- retical calculation. The possible mechanism of the removal process was also discussed.
A method was proposed for removing zirconium （Zr） from hydrous titanium dioxide （HTD） by the NaF solution. The effects of main parameters, i.e. pH values, NaF dosage, temperature and retention time, on the removal of zirconium were stud- ied. The optimal conditions were found as the following： pH value, 〈5.5; molar ratio of NaF to TiQ, 0.6; retention time, 80 min and temperature, 80℃. The removal rate of Zr under the optimized conditions was above 87.7%. The adsorption energy of the preferential absorption of hydrofluoric acid for Zr（OH）2SOt（OH2） on the （001） crystal surface of HTD was determined by theo- retical calculation. The possible mechanism of the removal process was also discussed.
基金
supports by the Major Program of the National Natural Science Foundation of China (No. 51090380)
the National Science Foundation for Distinguished Young Scholars of China (No. 51125018)
the National Natural Science Foundation of China (Nos. 51004091, 21006115,51104139)
