| China is a seriously water-poor country,and there's a large amount of wastewater generated from industrial factories,which contains a great amount of rare,toxic metal ions.With the advantages of large adsorption capacity,high adsorption rate and adsorption rate,simple operation method and low cost the chelating resin has been widly used in treatment of wastewater.A kind of side chain liquid crystal polyether chelating resin was synthesized with the polyether(prepared with the method of ringopening polymerization of epoxycyclohexane and epichlorohydrin)which grafted the 4-phenylphenol and used diethyl iminodiacetatethe as the chelating group to react with the production of blanc chloromethylation reaction.The adsorption property of Cu2+ was studied by EDTA titration,The specific research contents are as follows:(1)The backbone of copolyether which have a molecular weight of 1100 and the chlorine content of 22.2% was prepared by ring-opening polymerization with materials of cyclohexene oxide(monomer),epichlorohydrin(monomer),BF3ˇOEt2(catalyst),ethylene glycol(EG,initiator)and dichloromethane(solvent).The structure of the polymer was identified by FTIR.Investigated the regularity between the molecular weight of the polyether and the amount of initiator,the ratio of the monomers,the temperarure and the time,respectively.Finally,the conclusion that with the condition of the amount of the initiator is 2%,the ratio of epoxycyclohexane to epichlorohydrin is 2:3,the reaction temperature is 0?,and the reaction time is 5.5 h was best for preparing the polymer.(2)Prepared sodium 4-biphenylate by alkali method with the solvent of water and toluene,the material of 4-phenylphenol and Na OH,respectively.Studied the laws between the yields of the production and the temperature of different solvents,it can be find that with the increase of temperatures of water and toluene,the yield of former production was increased first and decreased later,the later production was increased gradually.The highest yields of water and toluene as solvents at their respective optimum conditions were 93.4% and 88.6%.(3)Grafted the mesogenic group into the backbone by williamson etherification reaction with the home-made polyether and sodium 4-biphenylate.The graft ratio was 70.8%.The structure of the polymer was studied by FTIR.The effects of solvent amount,reaction temperature and reaction time on the grafting rate were investigated.It was found that the reaction rate decreased with the increase of solvent amount,with the increase of temperature it increased first and then decreased,and with time goes the rate of graft increased first and remain unchanged later.(4)The former polymer was subjected to chloromethylation with the self-made chloromethylation BCMB and Blanco chloromethylation,respectively,with the chlorine content of the production was 10.1% and 13.9%.The chelate resin was made by grafting diethyl iminodiacetate into the chloromethylation.The structural properties and thermodynamic stability of the chelating resin were analyzed by FTIR,TG and DSC.The structure of the resin was identified and the thermal stability was good.The residual weight loss was 46.5%.It can be seen from the DSC curve that with the resin heating up,it entered into the liquid crystal phase at 86.8?,turned to the isotropic state from the liquid crystal state at 230?,and the resin has stable liquid crystal properties in a longer interval temperature.(5)The adsorption performance of chelating resin on Cu2+ was investigated by EDTA titration.The maximum static adsorption capacity of the resin was 18.67mmol/g,at the condition of p H=6,T=60°C,t=4 h,C0=0.15 mol/L.The chelating resin had the largest adsorption amount of Cu2+,which were 19.72 mmol/g,21.68 mmol/g,20.3 mmol/g,and 22.0 mmol/L,respectively.At the same time,the isothermal adsorption and kinetic studies of the chelating resin show that the adsorption behavior of the chelating resin on Cu2+ is consistent with the Langmuir and quasi-second-order kinetic equations.The adsorption and regeneration properties of Cu2+ were investigated.After 5 group of adsorption and desorption experiments,the adsorption capacity decreased by 14.7%,which indicated that the chelated resin has good adsorption and regeneration performance. |
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