| Two modification zeolites with special structure and performance were synthesized by modifying natural zeolite (NZ) using beta-cyclodextrin (β-CD) as modifying agent through the two different mechanisms and methodes. The modified zeolites were characterized with the modern analytical techniques such as fourier transform infrared spectroscopy (FTIR), elemental analysis, scanning electronic microscope (SEM), and Energy dispersive X-ray spectrometry (EDS) etc.. Through studying the adsorption capacity of modified zeolites on organic pollutant, heavy metal, and compound pollutants, the related mechanisms in adsorption of pollutants in water were investigated. This dissertation aimed to sumbit a theoretical basis in function and application of zeolites in order to provide a techno-basic in application of zeolites in water treatment, and to expend information for development of high-efficiency absorbents of safety, avirulence and environmental protection.The main contents and results were as follows:The novel modification methods of zeolites was presented using β-cyclodextrin (β-CD) as modifying agent. CCDMZ was obtained by modification zeolite using cationic β-CD (CCD) which was synthesized by2,3-expoxypropyl trimethylammonium chloride (ETMAC), and ECDMZ was obtained using epoxy chloropropane (EPI) as cross-linking agent through etherification to locate β-CD on NZ surface. The optimal preparation conditions of two modification zeolites were determined by studying the effects of preparaction condition on adsorption capacity (qe) of CCDMZ and ECDMZ, respectively. The results indicated that qe of CCDMZ was affected by the preparaction conditions of CCD (the concentration of β-CD, pH of solution, and METMAC:Mβ-CD), pretreament of NZ, concentration of CCD, and modification time etc.. The qe of ECDMZ was affected by pretreament of NZ, MEPT:Mβ-CD, reaction time, pH of solution, and percent of NaOH in solution etc.. The modern analytical techniques of FTIR, elemental analysis, SEM, and EDS were used to characterize the surface modification. The characterization results showed that β-CD could successfully be located on the surface of zeolites.The qe of CCDMZ and ECDMZ were investigated dealing with nitrophenols (NPs), heavy metals, para-nitrophenol (p-NP) and heavy metal ion of composite pollution system. The results indicated that the qe of CCDMZ and ECDMZ were affected by partical size, contact time, concentration and pH of solution etc.. The high qe of CCDMZ and ECDMZ on NPs and heavy metals was found at size fraction of0.45-0.9mm. Adsorption equilibrium times of CCDMZ and ECDMZ on NPs were60min and100min, respectively. The equilibrium times of Cu2+were120min, and that of Ni2+were120min and140min, respectively. The increas of concentration of NPs and heavy metals were favorable to the increas of qe. At an initial solute concentration of NPs of300mg/L, the qe of CCDMZ on p-NP,mid-nitrophenol (m-NP) and ortho-nitrophenol (o-NP) were335,220and324μg/g, and the qe of ECDMZ onp-NP, m-NP and o-NP were902,766and855μg/g, respectively. At an initial solute concentration of Cu2+and Ni2+of100mg/L, the qe of CCDMZ and ECDMZ on Cu2+and Ni2+were1267,1148μg/g and3751,3811μg/g, respectively. The effects of pH on qe of CCDMZ and ECDMZ were greatly visible because of the effect of changed pH on both morphological structure of NPs, Cu2+and Ni2+in solution and electrical charge structure of CCDMZ and ECDMZ. The adsorption effect of NPs and heavy metal ions on NZ, CCDMZ and ECDMZ was ECDMZ>CCDMZ>NZ. The adsorption process of CCDMZ and ECDMZ for NPs, Cu2+and Ni2+followed Langmuir isotherm and fitted with pseudo-second order. The results indicated that the adsorption process was physical absorption and chemical adsorption when the chemical adsorption mainly controlled the process. The n of Freundlich isotherm indicated that the adsorption of CCDMZ and ECDMZ for NPs, Cu2+and Ni2+were preferential, and the r of Langmuir showed that CCDMZ and ECDMZ were beneficial to treat low concentration water. For example, at an initial solute concentration of NPs of100mg/L, the qe of CCDMZ and ECDMZ on p-NP, o-NP and m-NP were increased8,5,13and23,14,37times than NZ. Thermodynamic study showed that the adsorption of NPs was a spontaneous and exothermic process, and the adsorption of Cu2+and Ni2+was a spontaneous and endothermic process. The adsorption results of mixed pollutants in the aqueous solutions indicated that the qe was decreased because of the mutual effects of β-NP and metal ions.
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