Surface modification of zeolite with b-cyclodextrin for removal of p-nitrophenol from aqueous solution

摘要

The surface of zeolite was modified by cationic b-cyclodextrin (CCD), which was synthesizednwith 2, 3-epoxypropyltrimethylammonium chloride (ETMAC) and b-cyclodextrin (b-CD), to preparena novel and effective sorbent for removal of p-nitrophenol (p-NP) from aqueous solution. FTIR,nSEM and EDS were used to characterize the surface modification. It was found that CCD, whichnwas synthesized at different conditions such as the mole ratio of ETMAC against b-CD and pH,nmade an impact on sorption capacity of p-NP on CCD-modified zeolite (CCDMZ). Given ETMAC:nb-CD ¼ 7:1 and pH ¼ 13, the cationic process of b-CD might be optimum for CCD to bond tonzeolite surfaces. In addition, CCD concentration and modification time affected sorption capacitynof p-NP on CCDMZ too. The sorption of p-NP on CCDMZ, activated zeolite (AZ) and natural zeoliten(NZ) was investigated by contact time, initial p-NP concentration and sorption isotherms with thenbatch sorption experiments. The results showed that the sorption of p-NP on CCDMZ satisfactorilynfitted the known Langmuir model and the sorption capacity of CCDMZ was higher than that of AZnand NZ although the contact time of CCDMZ appeared to be shorter than other two.