The Study On Preparation And Recognition By Surface Grafted Multiwalled Carbon Nanotubes Pb(Ⅱ) Imprinted Sorbent

Surface imprinting technique (SIT), which make the recognition site on the surface of supported material, so that, it can enhance the adsorption and desorption between recognition site and template molecular, and improve the extraction efficiency of imprinted sorbent. SIT, which is flexible, economical, environmental-friendly, highly selective, speedy, simple, rich in accessible sites, safe, easily automatic, has become a research hotspot in separation field. Lead, which is an important metal element, is widely applied to the field of commerce and industry. But as everyone knowns, lead causes a significant threat to the environment and social development. So, efficiently extraction and determination process of trace lead using for deal with leady castoff is particularly significant.However, the common analytical method of lead by the instrumental techniques including atomic absorption spectrometry (AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) is still difficult to direct use because of the very trace content and the many interference factor presence. Pre-concentration and selective separation of lead prior to its determination is required. SIT is just about a kind of sampling pre-treatment technique which aim at the separation and pre-concentration of trace material in complex samples. Therefore, the work is focused on the selective surface grafted Pb(Ⅱ) imprinted sorbent and separation of trace Lead with SIT, this dissertation consists of three parts, as follows:1. Comprehensive analysis and presentation are given for the principle of imprinting technique, progress in surface imprinted technique and the separation and determination of Pb(II) in recent years.2. A novel surface-grafted Pb(Ⅱ)-imprinted carbon nanotubes sorbent has been synthesized, using lead(Ⅱ)-6,6’-((1E,1’E)-(pyridine-2,6-diylbis(azanylylidene))bis(methanyly lidene))bis(2-allylphenol)(PDABMBAPOL) as functional monomer and template molecule. EGDMA as cross-linker and MCNTs as base material. Fourier transform infrared spectroscopy (IR) and scanning electron microscopy (SEM) were used to characterize and analysis the composite structure. Parameters affecting the separation and pre-concentration and extraction of Pb(Ⅱ) from the river, tap and waste water were also discussed using batch process. And a new method for determining traces Pb(Ⅱ) in environmental water samples is developedn with satisfactory results.3. A new type of surface imprinted material for selective separation of lead was prepared using lead(Ⅱ)-4-vinylpyridine-PDABMBAPOL complex as functional monomer and template molecule, EGDMA as a cross-linker and AIBN as initiator. and it was applied to determination of lead in actual samples with satisfactory results.