Luster Enbal, Avisar Dror, Horovitz Inna, Lozzi Luca, Baker Mark A, Grilli Rossana, Mamane Hadas
The Water Research Center, School of Earth Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
Nanomaterials (Basel). 2017 Jul 31;7(8):206. doi: 10.3390/nano7080206.
The photocatalytic degradation of the model pollutant carbamazepine (CBZ) was investigated under simulated solar irradiation with an N-doped TiO₂-coated Al₂O₃ photocatalytic membrane, using different water types. The photocatalytic membrane combines photocatalysis and membrane filtration in a single step. The impact of each individual constituent such as acidity, alkalinity, dissolved organic matter (DOM), divalent cations (Mg and Ca), and Cl on the degradation of CBZ was examined. CBZ in water was efficiently degraded by an N-doped TiO₂-coated Al₂O₃ membrane. However, elements added to the water, which simulate the constituents of natural water, had an impact on the CBZ degradation. Water alkalinity inhibited CBZ degradation mostly due to increase in pH while radical scavenging by carbonate was more dominant at higher values (>200 mg/L as CaCO₃). A negative effect of Ca addition on photocatalytic degradation was found only in combination with phosphate buffer, probably caused by deposition of CaHPO₄ or CaHPO₄·2H₂O on the catalyst surface. The presence of Cl and Mg ions had no effect on CBZ degradation. DOM significantly inhibited CBZ degradation for all tested background organic compounds. The photocatalytic activity of N-doped TiO₂-coated Al₂O₃ membranes gradually decreased after continuous use; however, it was successfully regenerated by 0.1% HCl chemical cleaning. Nevertheless, dissolution of metals like Al and Ti should be monitored following acid cleaning.
采用不同类型的水，在模拟太阳光照射下，使用氮掺杂二氧化钛包覆的氧化铝光催化膜，研究了模型污染物卡马西平（CBZ）的光催化降解情况。该光催化膜将光催化和膜过滤整合在一个步骤中。考察了酸度、碱度、溶解有机物（DOM）、二价阳离子（Mg和Ca）以及Cl等各成分对CBZ降解的影响。水中的CBZ能被氮掺杂二氧化钛包覆的氧化铝膜有效降解。然而，模拟天然水成分添加到水中的元素对CBZ降解有影响。水的碱度主要通过提高pH抑制CBZ降解，而在较高值（>200mg/L以碳酸钙计）时，碳酸根的自由基清除作用更为显著。仅在与磷酸盐缓冲液共存时发现添加Ca对光催化降解有负面影响，这可能是由于磷酸氢钙或磷酸氢钙二水合物沉积在催化剂表面所致。Cl和Mg离子的存在对CBZ降解没有影响。对于所有测试的背景有机化合物，DOM均显著抑制CBZ降解。连续使用后，氮掺杂二氧化钛包覆的氧化铝膜的光催化活性逐渐降低；不过，通过0.1%HCl化学清洗成功实现了再生。尽管如此，酸洗后应监测Al和Ti等金属的溶解情况。
