Study On The Preparation Of Gentian Violet,Cu(Ⅱ),Cr(Ⅲ) And Ni(Ⅱ) Molecular Imprinted Polymer And Its Adsorption Performance

Cr(III)ion imprinted polymer(Cr(III)-MIP),Cu(II)ion imprinted polymer(Cu(II)-MIP),Ni(II)ion imprinted polymer(Ni(II)-MIP)and Gentian Violet molecular imprinted polymer(GV-MIP)were synthesized by solution polymerization respectively.Cu(II),Cr(III),Ni(II)and Gentian Violet(GV)as the template molecule,acrylic acid(AA)or oleic acid as monomer,N,N-methylene bisacrylamide(MBA)or divinylbenzene(DVB)as crosslinking agent,azodiisobutyronitrile(AIBN)as the initiator.The structure and morphology were characterized by scanning electron microscopy(SEM)and infrared spectroscopy(FTIR),and the maximum adsorption capacity,adsorption selectivity,swelling ratio and recycle efficiency were determined.The adsorptionkinetics,adsorption isotherm and adsorption thermodynamics were studied and the microscopic adsorption mechanism was further analyzed.The results showed that the adsorption capacity of molecularly imprinted polymers increased with the increase of the concentration of imprinted molecular,and was much larger than that of the non imprinted polymer.The maximum adsorption capacity of Cr(III)-MIP,Cu(II)-MIP,Ni(II)-MIP and GV-MIP on the templatemolecules were 69.49 mg g-1and 95.41 mg g-1,91.63 mg g-1 and 1499.70 mg g-1,respectively.The amount of adsorption capacity of GV-MIP to Cr(III),Cu(II),Ni(II)were 126.16 mg g-1,451.24 mg g-1,302.73 mg g-1,respectively.Scatchard analysis found that there is a high and low binding sites.The results show that the adsorption process accords with Weber-Morris adsorption model and Langmuir adsorption isotherm model.Adsorption thermodynamics shows that the adsorption process is entropy decreasing,because of the adsorbed template molecules onto the surface of the polymer solution reducing the degrees of freedom,thereby the disorder of molecular motion on the two phase interface is reduced.The results also showed that the adsorption process was an exothermic process.