漂浮型B、N共掺杂TiO_2光催化剂的制备及柴油降解性能

以膨胀珍珠岩为载体,采用溶胶-凝胶法制备硼、氮共掺杂漂浮型Ti O_2,采用XRD、BET、SEM、UV-vis DRS、XPS等分析手段进行材料表征并考察其对柴油的光降解性能.结果表明,B-N-Ti O_2/EP复合光催化剂表面有明显的Ti O_2覆层,晶型为锐钛矿型Ti O_2,Ti O_2负载有利于比表面积的提升.制得的B-N-Ti O_2/EP的可见光区响应高于N-Ti O_2/EP和Ti O_2/EP,该结果与3种材料的柴油光降解效果相一致.B-N-Ti O_2/EP对柴油的9h降解率将近50%,GC-MS分析表明,光降解过程中柴油各特征组分(C_9~C_(23))均得到不同程度降解,其中C_(11)以下的短链有机分子降解效果明显.

Preparation of B-N co-doped TiO2 floating photocatalyst for degradation of diesel oil

Floating boron-nitrogen codoped TiO₂ grafted on expanded perlite (B-N-TiO₂/EP) photocatalysts were prepared by a facile sol-gel method. The catalysts were characterized by XRD, BET, SEM, UV-vis-DRS and XPS. Furthermore, photodegradation of diesel oil was investigated to evaluate photocatalytic activities of B-N-TiO₂/EP. The TiO₂ layer whose patterns were identified as anatase were clearly observed on the surface of EP. The immobilization of TiO₂ could greatly improve the BET surface area of EP. Compared with that of N-TiO₂/EP and TiO₂/EP, the absorption band edge of B-N-TiO₂/EP exhibits an evident red-shift and the absorption intensity of visible region increases obviously. This result is in accord with their photodegradation efficiency of diesel oil. The 9h photodegradation rate of diesel oil for B-N-TiO₂/EP was nearly 50%. The GC-MS results showed all the diesel oil components (C₉~C₂₃) could be degraded and short-chain organic molecules ( < C₁₁) were more easily photodegraded.