Study On Preparation, Organic Functional Modification And Adsorption Performance Of MCM-41Mesoporous Material

With the accelerated pace of modern industrialization process, a large number of heavy metal ions of industrial wastewater have been discharged into the natural environment, which has caused great harm to human health. Since the mesoporous material has a high specific surface area, pore size, pore volume and a narrower pore size distribution, it is becoming an ideal adsorbent material.In this paper, in order to research the adsorption performance of MCM-41adsorbent for Cu2+, Zn2+, Pb2+, Cr3+four kinds of heavy metal ions, MCM-41mesoporous material was prepared by sol-gel method under alkaline conditions, in which cetyl trimethyl ammonium bromide was used as template agent, tetraethyl orthosilicate(TEOS) was used as silicon source. Subsequently, amino and mercapto modified MCM-41sorbents were prepared by copolycondensate and grafting methods with3-Aminopropyltriethoxysilane and3-Trimethoxysilylpropanethiol used as surface functional reagent. The adsorption properties of adsorbents for the four heavy metals was studied on the basis of the characterization of their structure and nature.The characterization analysis of the MCM-41and its organic functionalized mesoporous adsorption materials was taken by scanning electron microscopy(SEM), X-ray diffraction(XRD), nitrogen adsorption-desorption and fourier transform infrared spectroscopy(FTIR). IR test show that, amino group and mercapto group were successfully loaded on the surface of MCM-41material by co-polycondensation and post-grafting methods. XRD and scanning electron microscopy analysis showed that the modified adsorbents have retained the skeleton structural features of pure MCM-41mesoporous materials, but the degree of order suffered different degree of decline due to organic functional groups on the material surface.In order to research the adsorption properties about Cu2+, Zn2+, Pb2+, Cr3+four kinds of heavy metal ions under the condition of room temperature(25℃), MCM-41and its organic functionalized mesoporous materials were used as adsorbents, the result showed that the adsorption equilibrium time for four heavy metal ions was 180min. And the adsorbent performance by grafting method is always better than copolycondensation method. The adsorption properties of amino loaded organic functional adsorbent by grafting method for Cu2+, Pb2+, Cr3+is the best, the adsorption capacity reached218.56μmol·g-1,234.12μmol·g-1,179.07μmol·g-1respectively, which were improved by184%,123%and74%; And the adsorption performance of mercapto loaded organic functional adsorbent by grafting for Zn2+is the best, the adsorption capacity reached138.46μmol·g-1, which was improved by78%compared to the unmodified MCM-41.