Hydrolysis Of Wool And Chitosan Modified Fe₃O₄ Nanoparticles To Adsorpt Copper Ions

Based on the large specific surface area of nanomaterials and magnetic materials recycled to avoid secondary pollution characteristics,we obtained nano magnetic materials of Fe₃O₄-organic compounds by using the precipitation method for the preparation of Fe₃O₄ magnetic nano particles and modifying nano magnetic Fe₃O₄ by wool hydrolysis with alkaline solution and chitosan. Through the modification to improve the appearance of Fe₃O₄ nanoparticles size and internal structure, at the same time improve the Fe₃O₄ adsorption capacity of copper ions in water.First, a certain amount of wool fibers were dissolved at a certain concentration of sodium hydroxide and temperature.In the process of preparing nano-sized Fe₃O₄ with ferric chloride and ferrous chloride as source of iron and sodium hydroxide as precipitating agent,different volumes of wool hydrolysis solution were added to modify Fe₃O₄ nanoparticles.Single factor analysis of the amount of added volume of wool hydrolysis solution was used to optimize the strongest capacity of the copper ion adsorption corresponding the volume of wool hydrolysis solution. Secondly, the Fe₃O₄ powders prepared by the precipitation method were modified by silane coupling agent, and then the magnetic nano-powder by coupling was processed into the degradation of chitosan solution to be modified.Then the phase, structure, morphology and components of Fe₃O₄ and Fe₃O₄ modified by wool hydrolysis solution and chitosan were characterized by means of scanning electron microscopy, transmission electron microscopy, X-ray spectroscopy, X-ray diffraction,specific surface area, thermal gravimetric analysis and testing and a vibrating sample magnetometer was used to measure the modified and unmodified Fe₃O₄ magnetic energy.Finally, the adsorption capacity of Fe₃O₄ to the copper ion, adsorption isotherm, adsorption kinetics, adsorption thermodynamics and so on were measured by UV-visible spectrophotometer. Test results showed that:（1） After adding wool hydrolysis solution improved Fe₃O₄ for the capacity of the copper ion adsorption. Different volumes of wool hydrolysis solution had varying degrees of increase in Fe₃O₄ adsorption capacity and the test found that when added 60 m L wool hydrolysis solution, the modified Fe₃O₄ acheieved the strongest capacity of the copper ion adsorption and was more 40% than the unmodified Fe₃O₄.（2）The copper ion removal rate was 25% higher than that of unmodified Fe₃O₄ after modification by chitosan.（3）N and S elements were found in the internal of Fe₃O₄ modified by wool hydrolysis solution.（4） After modified by wool hydrolysis solution and chitosan, particle size was similar to unmodified Fe₃O₄ and particle size were in the nanometer level. After modification, the BET Surface Area, t-Plot Micropore Area, BJH Adsorption and Desorption average pore width were decreased.（5）The nano Fe₃O₄ modified by wool hydrolysis solution and chitosan on copper ion adsorption fitted the highest degree in Langmuir isothermal adsorption model and quasi second order kinetic model.（6）For Fe₃O₄ nanoparticles modified by wool hydrolysis solution chitosan, Gibbs free energy change was less than 0, enthalpy and entropy change was greater than zero.