摘 要: | In order to study the influences of functionalized groups onto the adsorption of tetracycline,we prepared a series of amino and amino–Fe~(3+)complex mesoporous silica adsorbents with diverse content of amino and Fe~(3+)groups(named N,N-SBA15 and Fe-N,N-SBA15).The resulting mesoporous silica adsorbents were fully characterized by X-ray powder diffraction(XRD),Fourier transform infrared spectrometer(FTIR)and N_2adsorption/desorption isotherms.Furthermore,the effects of functionalized groups on the removal of TC were investigated.The results showed that the periodic ordered structure of SBA-15 was maintained after modification of amino/Fe~(3+)groups.The functionalized amino groups decreased the adsorption capacity while the coordinated Fe~(3+)increased the adsorption capacity.The adsorption kinetics of TC fitted pseudo-second-order model well and the equilibrium was achieved quickly.The adsorption isotherms fitted the Langmuir model well and with the Fe~(3+)content increased from 3.93%to 8.26%,the Q_(max)of the adsorbents increased from 102 to 188 mmol/kg.The solution p H affected the adsorption of TC onto amino complex adsorbents slightly while influenced the adsorption onto Fe-amine complex adsorbents greatly.The adsorption of TC on SBA15 and N,N-SBA15 may be related to the formation of outer-sphere surface complexes,while the adsorption of TC onto Fe-N,N-SBA15 was mainly attributed to the inner-sphere surface complexes.This study could offer potential materials that have excellent adsorption behavior for environmental remediation and suggested useful information for the preparing other adsorbents in environmental applications.
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