三维偕胺肟基生物高分子/氧化石墨烯凝胶的制备及对铀的吸附行为

It is the key to problem of the sustainable development, which reduces radioactive hazardous uranium from uranium resources processing. Uranium collection from radioactive effluent not only raises the comprehensive utilization of uranium, but also a significant way to protect ecological environment and human health. The preparation of 3D amidoxime- based biopolymers-magnetic graphene oxide gels and its adsorption behaviors for removal Uranium(Ⅵ) were investigated in this study. The 3D amidoxime-based biopolymers- graphene oxide gels (BGO-AO) was synthesized with higher adsorption capacity and better selectivity by optimizing preparation conditions(oxidation, cross-linking and surface modification). Adsorption behavior in static and dynamic method were studied to obtain the optimum adsorption/desorption and adsorption capacity. The reutilization of BGO-AO and desorption stability were studied. The mechanism and dynamics/thermodynamics of adsorption/desorption were investigated by using XPS, EDS,FI-IR and TEM during adsorption processing. This study has major academic significance in uranium resource processing, environment protection, and radioactive effluent treatment, and promotes sustainable development of regional economy in Jiangxi province with abundant of uranium resources.

减少铀资源开发过程中铀的放射性危害，是核工业可持续发展的关键课题。从铀采冶产生的放射性废水中回收铀，既能提高铀综合利用率，又能保护生态环境和人类健康安全。本课题拟开展三维偕胺肟基生物高分子/氧化石墨烯凝胶（3D amidoxime- based Biopolymers/Graphene Oxide gels, BGO-AO）制备及对铀高选择性吸附行为研究。通过对制备过程中（氧化、交联、表面修饰）条件研究，制备具有对铀离子吸附容量大、选择性好的吸附剂；研究BGO-AO对铀的静态及动态吸附/解吸行为，确定适宜的吸附/解吸条件，研究BGO-AO的重复利用价值和解吸稳定性；结合XRD、 EDS、 FT-IR、TEM等分析技术，揭示铀吸附/解吸机理和偕胺肟基对铀的高选择性机理；研究吸附过程动力学/热力学性质；预期研究结果能为吸附核素材料奠定理论基础，有利于推动铀矿资源丰富的江西地方经济可持续发展。

三维偕胺肟基生物高分子/氧化石墨烯凝胶对铀的高选择性吸附，能为吸附核素材料奠定理论基础，有利于推动铀矿资源丰富的江西地方经济的可持续发展有着重要的环境和资源意义。本项目开展了三维偕胺肟基生物高分子/氧化石墨烯凝胶制备及对铀吸附行为研究。.（1）生物高分子/氧化石墨烯的制备与表征。采用改良Hummer法制备不同氧化度的氧化石墨烯（GO），分别选用白蛋白（BSA）、羧甲基纤维素(CMC)、壳聚糖(CS)为生物高分子，添加相应的活化剂、引发剂，制备得到BSA-GO、CMC-GO、CS-GO。SEM、EDS、FT-IR、XRD、TGA表征结果证实交联成功。.（2）BSA-GO、CMC-GO、CS-GO对铀的吸附性能。三种吸附剂对水溶液中铀的吸附，最大吸附量分别为186.76 mg/g、322.58 mg/g、217.39 mg/g。吸附过程符合Langmuir模型和准二级模型，为化学吸附。吸附为吸热过程，反应可自发进行。.（3）偕胺肟化生物高分子/氧化石墨烯复合材料制备、表征。以BSA-GO、CMC-GO、CS-GO为原料，选用偶氮二异丁腈、硅烷偶联剂、丙烯腈、盐酸羟胺和二甲基亚砜等试剂与之接枝改性引入偕胺肟基团，制备出偕胺肟化生物高分子氧化石墨烯复合材料（BSA-GOAO、CMC-GOAO、CS-GOAO）。SEM、EDS、FT-IR、XRD、TGA表征结果证实偕胺肟化成功。.（4）BSA-GOAO、CMC-GOAO、CS-GOAO对铀的吸附行为。三种吸附剂应用于水溶液中铀的吸附，最大吸附量分别为238.10 mg/g、344.83 mg/g、263.20 mg/g。吸附过程符合Langmuir模型和准二级模型，吸附为自发进行的吸热过程。由于偕胺肟基团的引入，吸附剂对铀有较好的选择性，其中，CMC-GOAO对铀的选择性吸附率SU达到52.9%。