强碱性阴离子交换树脂在浓海水提溴中的应用

The Application of Strongly Basic Anion Exchange Resin in Bromine Extraction from Dense Seawater

研究201×7、201×4、D201 3种阴离子交换树脂对人工浓海水中的溴离子吸附性能,结果表明,201×7树脂的吸附效果最好。该树脂的静态饱和吸附量达到25.94 mg.g-1,流速为2.3 mL.min-1时的动态饱和吸附量为13.42 mg.g-1,因此选择201×7树脂作为吸附剂。通过静态吸附实验,测得298 K时吸附速率常数k298=1.7×10-3s-1;热焓ΔH=67.75 kJ.mol-1;在解吸过程中,确定了柠檬酸钠溶液作为解吸剂。201×7树脂吸附溴离子的过程符合Freundlich吸附等温式。通过动态吸附实验,研究了海水流速对201×7树脂吸附溴离子的影响。探讨了201×7树脂吸附溴离子的机理,结果表明,溴离子在201×7树脂上的吸附机理主要是Br-与—N+(CH3)3之间的静电作用。

The paper primarily discusses the adsorption property of 201×7、201×4 and D201 anion exchange resins for bromid ion in dense seawater.The results show that the 201×7 resin has a good adsorptivity for bromid ion.The capacity of static saturation adsorption for bromid ion in seawater is 25.94 mg·g-1,and the capacity of dynamic saturation adsorption at a velocity is 13.42 mg·g-1.Therefore,201×7 strongly basic anion exchange resin is selected for bromid ion adsorption.The absorption rate constant is k298=1.7×10-3s-1.The ΔH of adsorption is 67.75 kJ·mol-1.Through the experiment,sodium citrate is selected as desorption agent.The absorption of bromid ion on 201×7 resin follows the Freundlich isotherm.Furthermore,the influence of flow rate on adsorption is examined.The paper primarily discusses the adsorptive mechanics of 201×7 resin for bromid ion.It shows that the adsorptive mechanics of 201×7 resin for bromid ion is electrostatic effect between Br-and-N＋（CH3）3.