THE EFFECT OF TRACE ELEMENT DOPING ON THE TITANIUM DIOXIDE PHASE TRANSFORMATION
In the present work the influence of small amounts of the (K(Ⅰ), Na(Ⅰ), Si(Ⅳ), K(Ⅰ) Si(Ⅳ), Na(Ⅰ)-Si(Ⅳ), Zn(Ⅱ), Zr(Ⅳ), B(Ⅲ)) additives on the anatase-rutile phase transformation was determined. Solutions of doping agents were introduced to the starting material which was technical grade hydrated titanium dioxide (HTD). The prepared samples were calcined in different temperatures. The X-ray diffraction analysis was used to determine the anatase and rutile content in the calcined TiO2 samples. The influence of potassium additive on the anatase-rutile phase transformation was stronger than that of sodium. Inhibitory effect of SiO2 was higher at lower calcination temperature of HTD and when potassium was added simultaneously with SiO2. Mixed K2O/SiO2 and Na2O/SiO2 additives retarded the crystallite growth of the rutile whereby the influence of mixed Na2O/SiO2 additives was weaker than that of mixed K2O/SiO2 additives. The inhibitory effect of silica oxide on the anatase-rutile transformation can be explained by the formation of the anatase solid solution with silica. The addition of ZnO or B2O3 to TiO2 did not cause any change of the transformation temperature range but the transformation rate was higher below 750 ℃ and smaller above this temperature. The addition of ZrO2 to TiO2 did not cause any change of the anatase-rutile phase transformation temperature range, but the transformation rate was lower below 750 ℃ and higher above this temperature. Observed differences in the influence of ZnO, B2O3 or ZrO2 additives on the anatase-rutile phase transformation can result from different mechanisms of the reaction with titanium dioxide.
titanium dioxide anatase-rutile phase transformation additives
B. GRZMIL M. GLEN B. KIC K. LUBKOWSKI
West Pomeranian University of Technology, Szczecin, Institute of Chemical and Environment Engineering, Pu(l)askiego 10, 70-322 Szczecin, Poland
国际会议
北京
英文
761-766
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）