Synthesis Of Macroporous N-Methylimidazolium Function Alized Anion Exchange Resins For Adsorption Of Cr(Ⅵ)

Heavy metal chromium is very harmful to human health and it is urgently to solve the problems of chromium pollution. Ion exchange resin is a kind of network structured polymer compound which can realize the processes of adsorption, seperation and purity based on the carried functional groups with the ion exchange. Ion exchange resins are widely used various areas such as hydrometallurgy, wastewater treatment and so on.In this thesis, aiming to remove Cr(Ⅵ) from aqueous solution, N-methyimidazole functionalized macro porous anion exchange resins (PCl and P2SO4) were prepared by anchoring N-methyimidazole on macro porous choloromethylated copolymer of styrene-divinylbenzen (PS-DVB). It was shown that the prepared anion exchangers exhibited high thermal and chemical stabilities. The decompositon starting temperatures of PCl and P2SO4 are 226℃ and 215℃ respectively. PCl and P2SO4 resins also had good stability in acidic and basic degration agents. Moreover, on the basis of formulation of N-methyimidazole functionalized macro porous anion exchange resins prepared in the laboratory, the scale-up experiment was conducted in the pilot plant. The problem of engineering amplification was initially solved. The ratio of reactants and the process conditions were optimized. The contract requirment was met by the pilot test products and the yield ofPCl is 91.54-94.1%.For the remove of Cr(VI) from aqueous solution, the results of static adsorption test indicated that the N-methyimidazole functionalized macro porous anion exchange resins PCI and P2SO4 exhibited high adsorption efficiency and selectivity. The adsorption process is exothermic. The maximum Cr(VI) adsorption capacities are 188.4 mg/g and 157.8mg/g for PCI and P2SO4 respectively. The fixed bad column model results exhibited that the adsorption capcity of PCI resins was 61.01 mg/mL and the characteristic of PCI resins were higher adsorption amount, higher efficiency and bigger treatment capacity. Moreover, the PCI and P2SO4 had excellent reusabilities. In summary, all the experimental results, proved that the N-methyimidazole functionalized macro porous anion exchange resins show high practical application prospects in chromium pollution treatment.