含钛高炉渣制备二氧化钛晶须的研究

Study of TiO_2 whiskers prepared with tataniferous blast-furnance slag

以承德钢铁公司含钛高炉渣以及石英、硼酸、硼砂为主要原料,将配料组成选择在Na2O-CaO-Al2O3-B2O3-SiO2-TiO2系的分相区域,其中炉渣质量分数为50%～72%。将混合均匀的配料在1 250℃高温厢式电阻炉中熔融制得玻璃样品,对玻璃样品在700～900℃进行热处理制备二氧化钛晶须。用X射线衍射(XRD)、扫描电镜(SEM)对样品进行物相和形貌分析,结果表明:热处理温度为850℃时析出直径为0.5～1μm、长径比大于50的钛酸钙(CaTiO3)晶须。样品组成中氧化钠的含量对钛酸钙晶须的生成影响较大,氧化钠的引入导致[BO3]向[BO4]转变,促进系统分相,使分相界面增多,提供了有利的成核位,促进了晶须的生长。样品的光催化效率最高可达58%。

Using titanium-bearing blast furnace slag （mass fraction, 50%-72%） of Chengde Iron and Steel Company, quartz, boric acid, and borax as the main raw materials, composition selecting in the phase-separation region of the Na20-CaO- A1203-B203-SiO2-Ti02 system,the glass sample was prepared through mixed batch and melted at 1 250℃ in a van-type electric furnaee.TiO2 whiskers were achieved by heat-treatment to the glass sample at 700-900℃.The phase and morphology of the sample were analyzed by XRD and SEM.Resuhs indicated that the diameter of CaTi03 whiskers was 0.5-1 μm, and the aspect ratio was more than 50 ,when the heat-treatment was at 850℃. The Na20 content in the composition of the sample had great influence on the generation of CaTiO3 whiskers.Through adding Na20 to the glass composition, the [ B03 ] of glass system transformed to [ BO4] and the glass phase separation interfaces increased, then favorable nucleation sites promoted the growth of the whiskers.The photoeatalytie efficiency of the sample could reach 58%.