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Nanomaterials are a novel class of functional materials, and has broad prospects for application in bio-separation, Drug Delivery, immunoassay and biosensors. Magnetic nanomaterials characteristic differs from a conventional magnetic material, due to its small particle size, large surface area, and having excellent magnetic properties and therefore favored by many researchers, but are more easily compared to other nanomaterials agglomeration or oxidation, thus the magnetic nanoparticles modified to become the entry point of the study. The surface modification on the particle surface with physical or chemical methods for processing, the destination change the physical and chemical properties of the particle surface, such as surface chemical structure, surface hydrophobicity, chemical adsorption and reaction characteristics. Nano Fe0 Fe304 particle surface characteristics, usually the surface of the particles coated with a layer of inorganic or organic, mainly in order to improve its oxidation resistance, biocompatibility, and the use of solvent in dispersibility, stability, etc.. In addition, it is also possible according to the use requirements, imparted by the surface-modified Fe0, of Fe3O4 different particle surface reactive functional groups (such as-COOH,-NH2,-OH, etc.), so that the surface features and having different functions. The main content of this paper: First microemulsion synthesis of a relatively narrow particle size distribution, dispersion of zero-valent nano-iron, then γ-aminopropyl triethoxysilane introduced by the sol-gel method to the zero-valent iron nano- surface by infrared spectroscopy and transmission electron microscopy analysis to determine the particle diameter of magnetic nanoparticles is 20 to 30 nm. Investigated the adsorption of Pb2 and acidic scarlet GR, reactive brilliant red K-2BP performance and mechanism. (1) Pb2 adsorption properties and mechanism of effects of different quality nanoscale iron adsorption time, temperature and the proportion of gamma-aminopropyl triethoxysilane modified zero-valent iron nano-adsorption of lead ions in water performance adsorption activation energy 17.30kJ/mol, and the pre-exponential factor k0 = 18.75min-1 (2) of the azo dye Acid Scarlet GR, reactive brilliant red K-2BP removal performance, determine the best PH value 4-5, adsorption equilibrium time for 12h, the concentration of 100mg / L of acid scarlet and The maximum adsorption capacity of reactive red aqueous solution to achieve a balance in optimum adsorption conditions are 121.06mg / g and 191.5mg / g and the adsorption kinetics of the the langmuir adsorption kinetics equation, adsorption rate equation meets once a kinetic equation. Secondly prepared triethylene tetramine modified functionalized iron oxide nanoparticles with a core-shell structure, and its adsorption properties of Cd2. The experiments first use solvothermal method of uniform particle size, good dispersibility of the magnetic nanoparticles, and the sol-gel method TEOS hydrolysis prepared of Fe3O4 _AT_ SiO2, gamma-glycidoxypropyl trimethoxy silane play a bridging role, and thus triethylene tetramine introduced into the surface of the iron oxide. The prepared structure are as follows: Fe3O4 @ SiO2 @ KH-560 @ TETA. Products were infrared spectroscopy, XRD, thermogravimetric analysis, and transmission electron microscopy analysis and magnetic properties analysis to study the conditions of sorption time, the concentration of the solution PH value, the following conclusions: the product of the particle size concentration dispersed in the 200-300nm, phase spinel structure, a core-shell structure, the thickness of the cladding layer is about 30-50nm, and the saturation magnetization is still as 39.21emu / g. Determine Cd2 best adsorption PH value of 6 to 7, the maximum adsorption capacity for 657.9mg / g. Experimental adsorption isotherms fit well with the Freundlich isotherm model to meet the secondary adsorption kinetics rate equation.
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