基于对硝基苯酚光催化还原的聚间苯二胺类光催化材料的制备

发布时间：2018-05-03 02:37

  本文选题：对硝基苯酚 + 光催化　； 参考：《西华师范大学》2017年硕士论文

【摘要】：随着社会经济的快速发展和人民生活水平的提高,环境污染问题成为全社会所面临的核心问题。有机污染物的大量排放成为水环境日益恶化的重要原因之一,其中含对硝基苯酚的废水成为比较突出的一种。近年来,随着人们对半导体光催化技术的深入研究,发现其在催化还原有机污染物方面有着广阔的应用前景。半导体光催化技术因具有较高的催化氧化能力和回收再利用等优点被广泛应用于废水处理,但是目前的半导体光催化材料大多含有金属组分,表现出光响应范围窄、带隙较宽、价格昂贵、易对环境造成二次污染等缺点,在实际应用中受到一定的限制。随着一种不含金属组分、价格低廉、合适的能带结构的石墨相氮化碳的开发与研究,开启了聚合物类半导体光催化材料的研究方向。因此,开发一种高活性、高稳定性、不含金属组分的可见光催化剂成为光催化技术领域研究的热点。根据上述问题,本论文合成了一类具有光致发光性质的聚合物半导体光催化材料,并应用于对硝基苯酚的催化还原的应用中,具体内容如下:1.以间苯二胺(mPD)和罗丹明B(RhB)为单体,过硫酸铵(APS)为引发剂,经过高温水热法合成了具有光致发光性质的聚间苯二胺-罗丹明B共聚物量子点(PmRDs)。实验表明该聚合物具有良好的光致发光的性质,在一定波长范围内对可见光有良好的吸收能力,因此在对对硝基苯酚催化还原中表现出高效的催化性能。在氙灯的照射下,6 mg/m L的催化剂就能将1×10-3 M的对硝基苯酚(4-NP)在5 min完全催化,通过计算其速率常数可高达0.766 min-1(25℃)。我们还研究了不同pH、温度、不同范围的波长、催化剂量对4-NP的催化性能的影响。将合成的催化剂与其他含有金属组分的催化剂相比较,发现PmRDs在可见光的照射下具有较高的催化活性。2.以间苯二胺和甲基橙(MO)为单体,在过硫酸铵引发剂的作用下,采用一步水热法合成了间苯二胺-甲基橙共聚物催化剂(Pm-MO)。通过实验发现,在24W的节能灯的照射下,6 mg/m L的催化剂可将相同浓度的4-NP在6 min的时间内完全催化,根据一级动力学方程,我们计算出该催化剂在25℃时其催化速率常数为0.30 min-1。其表现出优异的催化性能可能是由于间苯二胺和甲基橙聚合后的能带结构比较匹配,带隙较窄,光催化活性良好。3.罗丹明B和甲基橙属于染料分子,在使用过程中可能对环境造成二次污染,因此我们发现叶绿素对红光和蓝紫光有较强吸收,而菠菜中含有丰富的叶绿素,因此该实验利用间苯二胺和菠菜汁为原料,合成了具有光催化活性的聚合物材料。对该材料进行表征及光催化性能测试,发现该催化剂在紫外灯的照射下在60 min内能将4-NP催化完全。
[Abstract]:With the rapid development of social economy and the improvement of people's living standard, environmental pollution has become the core problem of the whole society. The discharge of organic pollutants has become one of the important reasons for the deterioration of water environment, and the wastewater containing p-nitrophenol has become a prominent one. In recent years, with the in-depth study of semiconductor photocatalytic technology, it is found that it has a broad application prospect in catalytic reduction of organic pollutants. Semiconductor photocatalytic technology has been widely used in wastewater treatment because of its high catalytic oxidation ability and recovery and reuse. However, most semiconductor photocatalytic materials contain metal components, showing a narrow range of light response and wide band gap. High price, easy to cause secondary pollution to the environment and so on, which is limited in practical application. With the development and research of a kind of graphite-phase carbon nitride with no metal component, low price and suitable energy band structure, the research direction of polymer semiconductor photocatalytic materials has been opened. Therefore, the development of a highly active, stable and metal-free visible light catalyst has become a hot spot in the field of photocatalysis technology. According to the above problems, a class of polymer semiconductor photocatalytic materials with photoluminescence properties were synthesized and applied to the catalytic reduction of p-nitrophenol. The main contents are as follows: 1. Poly (m-phenylenediamine-rhodamine B) copolymers with photoluminescence properties were synthesized by hydrothermal method using resorcinenediamine and rhodamine as monomers and ammonium persulfate (APS) as initiators. The experimental results show that the polymer has good photoluminescence properties and good absorption ability to visible light in a certain wavelength range, so it has high catalytic performance in the catalytic reduction of p-nitrophenol. Under the irradiation of xenon lamp, the catalyst of 6 mg/m / L can completely catalyze 1 脳 10-3 M p-nitrophenol 4-NPs for 5 min, and the rate constant can reach up to 0.766 min-1(25 鈩，

本文编号：1836622