Aligning Of CNTs And Its Application Inwater Treatment

CNTs (Carbon nanotubes) have been one of the hotspots in the nanomaterial field because of their unique physical and chemical properties, in recent year, its application in water treatment became an emphasis for the investigation in environment area.In this experiment, we employ ultrasonic for the acidic treatment of single (SWNTs) and multi wall (MWNTs) carbon nanotube. And use co-precipitation for the magnetization of multi-wall carbon nanotubes. The characterization of Fe-MWNTs was practiced by XRD and TEM and magnetization loop test, found that, there was nano Fe3O4 particle loaded on the surface of MWNTs with a diameter distributed in 10 to 50nm ,and the magnetization have magnified the magnetism of MWNTs obviously. Employing FT-IR,Roman and UV/Via for the analysis of SWNTs and ASWNTs, there was acidic functional groups produced during the acid treating, but there was no change in the wall diameter.Take 2,4-dichlorophenol and Cu²⁺ as reprerentiation of heavy metal and orgnic contamination respectively to study removal of CNTs to water contamination. Found that, it taken a very short time for each CNTs to became saturation, and the adsorption isotherm fitted Langmuir model well, in a short adsorption time, single-wall CNTs had a better adsorption capacity than multi-wall, acid treated outgone unaligned, and Fe-MWNTs had a worst adsorption effect. But, when we prolonged the adsorption time, the adsorption capacity of Fe-MWNTs became larger than MWNTs obviously. The adsorption capacity decreased with the increasing of temperature, and when increasing dosage of MWNTs, Q increased, but qe (adsorption of per gram CNTs) decreased. When adsorbing 2,4-dichlorophenol, pH value below 4.0, there is about no change for qe, and it increased slowly when pH between 4.0～5.6, decreased rapid with the increasing of pH when it exceeded 5.6; When it was for the removal of Cu²⁺, qe increased expeditiously when pH was below 6.0, then it became gently.By density founctional theory calculation,found that, the adsorption of Cu²⁺ on the surface of SWNTs belonging to a strong physical adsorption, and the peak adsorption beyond the center adsorption; Both of the parallel and vertical adsorption of 2,4-dichlorophenol onto were some chemical adsorption, and parallel adsorption was better than vertical adsorption.