石墨烯-二氧化钛复合材料对泰乐菌素的吸附和光解研究

发布时间：2018-04-22 20:44

本文选题：泰乐菌素 + 石墨烯　；参考：《华南理工大学》2015年硕士论文

【摘要】：抗生素在医药和养殖业中的大量使用,使得众多抗生素以原药或代谢物的形式进入环境,由于这些抗生素仍具有一定的生物活性,将可能对生态环境产生潜在的危害。近年来,抗生素作为一种新兴的“假持久性”污染物,其在环境中的环境行为及污染控制受到了环境工作者的广泛关注。抗生素的去除技术存在着处理效率低,产生二次污染等缺点。Ti O2光催化氧化具有性质稳定,无二次污染以及对污染物的矿化程度高等优点,但由于其光催化特性只能在紫外光条件下激发,限制了其在污染控制领域的应用。为了提高对可见光的利用效率,本研究利用石墨烯对二氧化钛进行改性处理,制备出一种新型石墨烯-二氧化钛复合光催化材料(G-Ti O2),以泰乐菌素(tylosin,TYL)作为典型抗生素的代表,研究了G-Ti O2对TYL的吸附行为及在可见光条件下的光解特性,为抗生素污染控制提供技术支持。研究发现:1.以石墨烯为模版可以制备出一种石墨烯-二氧化钛复合材料,二氧化钛主要呈线状形式,其直径为20~50nm,排列在石墨烯表面,石墨烯和二氧化钛以Ti-O-C化学键结合,且石墨烯-二氧化钛复合材料中Ti O2为锐钛矿晶型。2.TYL在G-Ti O2上的吸附作用呈明显的非线性,吸附过程满足准二级动力学模型,吸附数据可以用Langmuir模型较好的拟合,吸附容量随着溶液p H值的增加而增加,总体吸附过程可能是静电作用、范德华作用力、氢键作用、表面络合作用共同作用的结果。3.在模拟自然光照条件下,G-Ti O2对TYL具有较好的光解效果,石墨烯掺杂量为1%时,复合材料对TYL的光解率可达55.4%,且具有较好的重复利用率。光解率与TYL的初始浓度呈反比;且随溶液p H值的增大呈现先增加后减小的趋势。G-Ti O2对TYL的光解机制可能与催化剂的电子-空穴分离效率提高有关。
[Abstract]:The extensive use of antibiotics in medicine and aquaculture makes many antibiotics enter the environment in the form of raw drugs or metabolites. Because these antibiotics still have certain biological activities, they may cause potential harm to the ecological environment. In recent years, antibiotics as a new "pseudo-persistent" pollutant, its environmental behavior in the environment and pollution control has been widely concerned by environmental workers. The removal technology of antibiotics has some disadvantages, such as low treatment efficiency, secondary pollution and so on. TIO 2 photocatalytic oxidation has the advantages of stable properties, no secondary pollution and high mineralization degree of pollutants. However, its photocatalytic properties can only be excited under ultraviolet light, which limits its application in pollution control field. In order to improve the efficiency of visible light utilization, a novel graphene composite photocatalytic material, G-TiO _ 2, was prepared by modifying titanium dioxide with graphene, and tylosin TYL was used as the representative of antibiotics. The adsorption behavior of G-Ti O 2 to TYL and the photolysis characteristics of G-Ti O 2 under visible light were studied in order to provide technical support for the control of antibiotic contamination. The study found that 1: 1. A kind of graphene-titanium dioxide composite can be prepared by using graphene as template. Titanium dioxide is mainly in linear form, and its diameter is 20 ~ (50) nm, which is arranged on the surface of graphene. Graphene and titanium dioxide are bonded with Ti-O-C chemical bond. Moreover, the adsorption of TIO _ 2 on G-Ti O _ 2 in graphene TIO _ 2 composite is obviously nonlinear, and the adsorption process satisfies the quasi-second-order kinetic model. The adsorption data can be well fitted by Langmuir model. The adsorption capacity increases with the increase of pH value of the solution. The total adsorption process may be the result of electrostatic interaction, van der Waals interaction, hydrogen bonding and surface complexation. Under the simulated natural light condition, G-TiO _ 2 has a good photodegradation effect on TYL. When the content of graphene is 1, the photolysis rate of the composite to TYL can reach 55.4%, and it has good reuse efficiency. The photolysis rate is inversely proportional to the initial concentration of TYL, and increases first and then decreases with the increase of pH value of the solution. The photolysis mechanism of G-TiO _ 2 on TYL may be related to the improvement of the efficiency of electron-hole separation of the catalyst.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X505;TB33

【参考文献】