氨基功能化淀粉基吸附剂的制备及其对铀酰离子的吸附行为

Starch is used as a raw material, and an amino ligand is introduced into the starch molecule using an esterification-crosslinking-ammonolysis three-step reaction to obtain an amino-functionalized starch-based adsorbent, which has the ability to chelate heavy metal ions. Using FTIR and EDS and other methods were used to characterize the surface chemical properties and element distribution of the adsorbent. The adsorption performance of amino-functionalized starch-based adsorbents for uranyl ions in aqueous solutions was studied, and the adsorption kinetics and adsorption thermodynamics were analyzed. The results showed that starch-based After the adsorbent is functionalized with amino groups, the adsorption performance of uranyl ions is significantly improved. The adsorption behavior of uranyl ions by amino-functionalized starch-based adsorbents conforms to the Langmuir isotherm adsorption model and quasi-second-order adsorption kinetic equations. The adsorption process mainly depends on Its surface-the coordination chelation between NH2 and uranyl ion, is an exothermic process. At pH=6, the initial uranyl ion mass concentration is 35 mg/g, the reaction temperature is 25 ℃, and the adsorbent is injected. Under the conditions of the addition amount of 0.25 g/L and the adsorption time of 5 h, the adsorption amount of the uranyl ion by the adsorbent was 118.92 mg/g. This shows that the amino-functionalized starch-based adsorbent has potential application prospects in the adsorption of uranyl ions.