| Currently,water-related problems resulted from economic development have been emerging one after another.Adsorptive resins have showed advantages that other resins can hardly match.As a typical adsorptive resin,magnetic acrylic resin is gaining growing popularity in water treatment for its good mechanical property,high adsorption rete,good separation capability,and easy operation.Acrylic resins can be functionalized with different groups and can be modified under specific conditions by adding modifying materials,so as to improve its performance for various applications.The main points of this thesis can be classified as follows:(1)Magnetic acrylic resins were successfully synthesized via suspension polymerization.Adjusting the monomer ratio,porogen content,and the types of porogen,we can obtaine the resin with best performance;Marked as D-70-T-125,it has good magnetic separation ability and a surface area of 549m2/g.The particle size is distributed in 100～250μm.This study also found that the content of divinylbenzene and the specific surface area of the resin show a linear correlation;the coefficient is 0.998.(2)The magnetic acrylic resin with best performance,D-70-T-125,was selected and modified with trimethylamine and di(4-hydroxy-2-trifluoromethyl)phenyl dithiophosphinic acid respectively.It was found that the specific surface area of the aminated resin reduced by 270 m2/g and the specific saturation magnetization was reduced by 0.7 emu/g.The specific surface area of the resin modified with bis(4-hydroxy-2-trifluoromethyl)phenyl dithiophosphinic acid reduced by 380 m2/g,indicating its volume of pore was reduced accordingly.the degree of the two modified resin was determined using XPS,it was found that the content of N of D-70-T-125 was as high as 2.04%,and The content of the resin D-70-T-125-DTPA(100%)which modified by bis(4-hydroxy-2-trifluoromethyl)phenyl dithiophosphinic acid,S is as high as 3.43%.(3)Using two kinds of magnetic acrylic resins D-70-T-125 and D-70-T-125-A,the magnetic resin E-70-T-125-A which does not contain divinylbenzene,and the magnetic resin D-100-T-125 whichdoes not contain Glycidyl methacrylate,Above four resins is 2-nitrotoluene(o-MNT),2,4-dinitrotoluene(DNT)and 2,4,6-trimethyltoluene(TNT)respectively.Three nitrobenzene adsorbates were tested for their adsorption properties.Three pollutants(2-nitrotoluene,2,4-dinitrotoluene and 2,3,5-trimethyltoluene three nitrobenzene),were selected as adsorbates to test adsorption properties of the two asynthesized magnetic acrylic resins.It was found that the adsorption capacity of the aminated magnetic acrylic resin to TNT was 323 mg/g,and that to DNT was only 81 mg/g.This study also found that the resins D-100-T-125 and D-70-T-125 adsorbed TNT in accordance with physical adsorption and monolayer adsorption characteristics.The adsorptions of DNT and o-MNT on the above four resins belong to physical and monolayer adsorption.The adsorption capacity of the resin is positively correlated with the specific surface area and the pore structure.(4)The magnetic acrylic resin modified with Bis(4-hydroxy-2-trifluoromethyl)phenyl dithiophosphinic acidwas chosen to study its adsorption of trivalent lanthanide and actinides.Results suggested that the adsorption reached equilibrium in 30min,the resins showed best adsorption performance at pH=6. |
