| In recent years, with the rapid development of various industries of China, industrial waste water emissions have shown a dramatic increase in the trend. It has been making a serious situation of water pollution, and the wastewater management task is urgent. Heavy metal wastewater is one of the most harmful industrial wastewater. It is urgent to greatly strengthen the research and practice to promote the development of heavy metal wastewater treatment technology. Adsorption is the most common way used for separation of heavy metals from wastewater among many techniques, such as ion exchange, precipitation, adsorption, membrane processes, reverse osmosis, sedimentation, electro-dialysis, etc. The effect of removing heavy metal ions depends on the performance of adsorbents. Molecular sieve is a noval adsorbent, it can be used for selective adsorption according to molecular size and configuration, especially for unsaturated molecules, polar molecules and easy polar molecule. Presently, molecular sieve adsorption process has been widely used in chemical industry, gas industry, petrochemical industry, environment protection and metallurgical industry. MCM-41 mesoporous molecular sieve discovered by researchers is a noval materials with one-dimensional, hexagonally ordered pore structure and large specific surface area. Therefore, MCM-41 possess many superiorities that other adsorbents can not compare, and it also has the industrialized promising.The surface of MCM-41 is covered with amounts of free silicic hydroxyl such as–Si(OH)3 and =Si(OH)2, which can react with silicon coupling agent and thus introduce alkyl, amido and sulfur hydroxyl groups into MCM-41. Moreover, other functional groups can be further introduced by these active groups and new organic-inorganic hybrid materials can be developed.In this paper, according to the hydrothermal crystallization method, mesoporous molecular sieve MCM-41 and BMS-3 were prepared using Cetyltrimethylammonium bromide as template. The two samples were characterized by SEM, N2 adsorption-desorption isotherms, surface area and pore size analysis, FT-IR, TGA and so on. The results showed that MCM-41 possess larger surface area and more evenly pore structure, thus MCM-41 was chose as the follow-up functional precursor. Then, the organic functional group -(CH2)3N(CH2COOH)2 was modified onto the mesoporous molecular sieve surface with active–OH groups by grafting treatment. Both of the modified and unmodified adsbents were characterized by contact angle, specific surface area and pore size analysis, FT-IR, TGA, elemental analysis and so on. The results proved that the organic functional groups have been successfully modified onto the surface of mesoporous molecular sieve, and the presence of organic groups has not altered the specific structure of MCM-41 matrix.Then, the adsorption properties of modified mesoporous molecular sieve were studied. The effects of the solution pH, metal ion initial concentrations, and contact time were investigated. The optimum conditions for the removal of metal ions at an initial concentration of 50 mg/L were 2 g/L of dose, pH 6.0 for Cu(Ⅱ), pH 5.0 for Pb(Ⅱ), 120 rpm of agitation speed and 40min of contact time. The maximum adsorption capacity for Pb(Ⅱ) was found to be 40.82 mg/g. The adsorption behavior of the modified adsorbent could be described by Langmuir model and Freundlich model at 298 K. However, it was found that Langmuir equation showed better correlation with the experimental data than the Freundlich equation.
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