Ag_(3)PO_(4)/P-C_(3)N_(4)材料的制备及其对铀的吸附性能北大核心CSCD

为设计一种对U(Ⅵ)具有较高吸附容量和较高选择性的吸附材料,采用石墨相氮化碳(g-C_(3)N_(4))与磷酸二氢铵作为原料,通过热共聚法制备P-C_(3)N_(4),再利用磷酸氢二钠与硝酸银通过原位共沉淀法制备Ag_(3)PO_(4)/P-C_(3)N_(4)复合吸附材料。吸附实验结果表明,Ag_(3)PO_(4)/P-C_(3)N_(4)复合吸附材料在室温下对U(Ⅵ)的吸附容量达到524.6 mg/g;在溶液中同时存在Na^(+)、K^(+)、Mg^(2+)、Ca^(2+)、Sr^(2+)、Zn^(2+)、Ni^(2+)和Co^(2+)等竞争离子时,对U(Ⅵ)的吸附分配系数达到6.13×10^(3)mL/g。XPS分析结果表明,Ag_(3)PO_(4)/P-C_(3)N_(4)复合吸附材料中的含N和含P官能团可能参与U(Ⅵ)吸附过程。因此,Ag_(3)PO_(4)/P-C_(3)N_(4)复合吸附材料是一种对U(Ⅵ)具有较高吸附容量和较高选择性的吸附材料。

Preparation of Ag3PO4/P-C3N4 Material and Uranium Adsorption Performance

In order to design an adsorption material with higher selectivity to U(Ⅵ) while ensuring a higher adsorption capacity, g C3N4 and ammonium dihydrogen phosphate were used as raw materials to prepare P C3N4 by thermal copolymerization. The Ag3PO4/P C3N4 composite adsorption material was prepared by in situ co precipitation method using disodium hydrogen phosphate and silver nitrate. The results of adsorption experiments show that the adsorption capacity of Ag3PO4/P C3N4 composite adsorbent for U(Ⅵ) reaches 5246 mg/g at room temperature; the distribution coefficient to U(Ⅵ) reaches 613×103 mL/g with competing ions such as Na+, K+, Mg2+, Ca2+, Sr2+, Zn2+, Ni2+ and Co2+ in solution. XPS analysis result shows that the N and P containing functional groups in the Ag3PO4/P C3N4 composite adsorption material may participate in the U(Ⅵ) adsorption process. Therefore, the Ag3PO4/P C3N4 composite adsorption material is one kind of adsorption material with higher adsorption capacity and higher U(Ⅵ) selectivity.