Study On Synthesis Of Uranyl Imprinted Ion Exchange Resin And Its Recognition Characteristics

Molecular imprinting technology (MIT) with high selectivity and affinity is developed rapidly in recent three decades. Ion exchange technology is widely used in uranium extraction and separation. During the researching, we synthesized a new kind of amine monomer for synthesis imprinted ion exchange resin. Then, a kind of uranyl sulphate imprinted ion exchange resin with amine function group is synthesized using MIT for the first time. Some experiments were also taken to testify the performance of the imprinted ion exchange resins. On basis of a brief introduction about MIT in principle, recent applications and progresses, and about common uranium separation method and it's defects. The following three aspects were studed in this thesis:First, diethyl allylamine(DEAA) is synthesized at normal pressure and without catalysis, using allyl chloride(AC) as alkylation reagent. The affection of proportion of material, reaction time, method and time of feeding, and time of boiling is discussed. The investigation indicated a yield of 78% in the optimal conditions as follows: mol ratio of allyl chloride: diethyl amine= 1.1:1, reaction temperature=40, feeding time=2h, boiling time =lh. The content of DEAA in redistillate reachs 98%.Secondly, the uranyl imprinted ion exchange resin for purifying uranium effluent from uranium mining and metallurgy is presented in water by copolymerization of styrene with functional monomer DEAA and crosslinker divinylbenzene, using uranyl sulphate as template and azobisisobutyronitrile as initiator. We also discussed factors influencing polymerization such as ratio of styrene: divinylbenzene, selection of initiator, selection of functional monomer, option of initiatory prerequisite and so on.Finally, the adsorption character and selective recognition ability of the MIPs were investigated. The results showed that MIPs-1 resin, MIPs-3 resin, MIPs-4 resin and MIPs-5 resin can be used in a large pH range from 1 to 6, but the adsorption rate is highest when pH=2 for all imprinted or un-imprinted resins. At the same time, compared with 201× 7 strong base type anion ion exchange resin and medium pore resin D263, imprinted ion exchange resin MTPs-4 show better adsorption property and fast adsorption rate. In acid medium, when adsorption reaches equilibrium, the total distribution coefficients of uranium on D263, 201 X 7 and MIPs-4 resin are 0.179, 0.110 and 0.249L/g respectively. When P (U)=1.0mg/ml in effluent, the contact time is 4 minutes, breakthrough point(or breakthrough capacity) of D263, 201×7 and MIPs-4 resin are 20BV(19.6mg/ml), 18BV(17.6mg/ml) and 22BV(21.6mg/ml), and saturated capacity are 39.4, 35.2 and 36.2mg/ml respectively. The MIPs-4 resin's elution property is better than D263 resin and 201× 7 resin. Using the 0.05M H2SO4 and 1.0M NaC1 as elution solution, the elution volume is only about 4.0BV. The MTPs-4 resin also shows better operation property in dilute uranium solution among those kind of resins,...