The Application Of Typical Modified Nanomaterials In The Filed Of Environmental Pollution Control

In recent years, living and production standard have been improved with the development of science and technology, but the the serious pollution has been found in environment. The air pollution was caused by NOx (typical environmental pollution). Thus, the paper was foused on the study of the removal of NO.1. In the paper, highly ordered mesoporous MnO2 has been prepared using KIT-6 as hard template for the selective catalytic reduction (SCR) activity of NO with NH3 at low temperature, which was characterized by TEM, XRD, BET, XPS, H2-TPR, NH3-TPD and in-situ DRIFT. As comparison, mesoporous Mn2O3 and bulk MnO2 have been synthesized and used to test their NO conversion at the same parameters. It is found that the NO conversion of three samples can be reached maxium in 200℃. The NO conversion of ordered mesoporous MnO2 can reach 100% in 200℃, and the NO conversion of ordered mesoporous MnO2 was all more than from 150 to 250℃. The NO conversion of mesoporous Mn2O3 with 94.35% is little lower than ordered mesoporous MnO2, however, the NO conversion of bulk MnO2 with 58.35% is apporoximately half of mesoporous MnO2.Furthermore, its mechanism of improved SCR performance has been investigated, and it is indicated that specific surface area, surface chemisorbed oxygen, reducibility and acid sites have great effect on the SCR reaction based on results of XPS, H2-TPR, NH3-TPD and in situ DRIFT. In addition, the effect of H2O, GHSV, NH3 and O2 on NO conversion has been investigated.The serious water pollution caused by bacteria has been drawn more and more concentration. Thus, the paper was foused on the study of the removal of bacteria.2. Magnetic Fe3O4/graphene composite (abbreviated as G-Fe3O4) was synthesized successfully by solvothermal method to effectively remove both bacteriophage and bacteria in water, which was tested by HRTEM, XRD, BET, XPS, FTIR, CV, magnetic property and zeta-potential measurements. Based on the result of HRTEM, the single sheet structure of graphene oxide and the monodisperse Fe3O4 nanoparticles on the surface of graphene can be observed obviously. The G-Fe3O4 composite were attractive for removing a wide range of pathogens including not only bacteriophage ms2, but also various bacteria such as S. aureus, E. coli, Salmonella, E. Faecium, E. faecalis and Shigella. The removal efficiency of E. coli for G-Fe3O4 composite can achieve 93.09%, while it is only 54.97% with pure Fe3O4 nanoparticles. The effect of concentration of sample, concentration of bacteria and contact time on the removal efficiency of bacteria was investigated. Moreover, a detailed verification test of real water samples was conducted and the removal efficiency of bacteria in real water samples with G-Fe3O4 composite can also reach 94.8%. In addition, the removal mechanism was investigated by Fluorescent-based cell live/dead test.