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采用溶胶-凝胶法制备稀土元素La掺杂TiO_2(La/TiO_2)纳米光催化剂,通过X射线衍射(XRD)、紫外-可见漫反射(UV-Vis DRS)和低温N2物理吸附测试手段对其进行表征,并以浮选捕收剂酯-105为处理对象考察了溶液初始p H值、La掺杂比、煅烧温度、光照强度、催化剂用量以及催化剂重复利用对催化剂活性的影响。表征结果表明,La的掺杂能够抑制TiO_2的晶粒生长,增大其比表面积,扩大其对可见光的响应,从而提高其光催化活性;煅烧温度过高会因TiO_2发生烧结团聚而使其粒径增大、比表面积减小,从而影响其光催化活性。酯-105降解试验结果表明,初始p H为6.30(原溶液)、La掺杂比为0.50%、煅烧温度为450℃、光照为汞灯300 W、催化剂用量为0.3 g·L-1时,光催化活性最强,70 min后,酯-105降解率达99.59%;经验证,该催化剂重复使用4次后,酯-105降解率仍在99%以上,为La/TiO_2的工程实践应用提供了可能。
La-doped TiO 2 (La / TiO 2) nanostructured photocatalysts were prepared by sol-gel method. Their properties were characterized by X-ray diffraction, UV-Vis DRS and N2 adsorption- The effects of initial pH, La doping ratio, calcination temperature, light intensity, catalyst dosage and catalyst recycle on the catalyst activity were investigated by using flotation collector Ester-105 as the target. Characterization results show that La doping can inhibit the grain growth of TiO 2, increase its specific surface area and enlarge its response to visible light, so as to enhance its photocatalytic activity. When the calcination temperature is too high, Diameter increases, the specific surface area decreases, thus affecting its photocatalytic activity. Ester-105 degradation test results showed that the initial p H was 6.30 (the original solution), the La doping ratio was 0.50%, the calcination temperature was 450 ℃, the light was 300 W and the catalyst dosage was 0.3 g · L -1. The photocatalytic activity was the strongest. After 70 min, the degradation rate of ester-105 reached 99.59%. It was verified that the degradation rate of ester-105 remained above 99% after repeated use of the catalyst for four times and was provided for engineering application of La / TiO_2 It is possible.