Fe_(3)O_(4)@SA/GO凝胶球的制备及对亚甲基蓝的吸附性能

Preparation of Fe_(3)O_(4)@SA/GO gel ball and its adsorption performance towards methylene blue

以海藻酸钠为骨架,结合Fe_(3)O_(4)及氧化石墨烯制备了Fe_(3)O_(4)@SA/GO复合凝胶球。采用SEM、FT-IR、XRD、VSM等对制备的材料进行了表征分析,并且考察了Fe_(3)O_(4)@SA/GO对水中亚甲基蓝的吸附性能。结果表明:Fe_(3)O_(4)@SA/GO凝胶球空隙较多,表面含有丰富的羧基、羟基等含氧官能团;材料磁性能良好,饱和磁化强度达到了17.88 emu·g^(−1),具有超顺的磁性;在25℃、pH=9的条件下,投加量为1 g·L^(−1)的吸附剂对100 mg·L^(−1)亚甲基蓝吸附300 min,吸附率达到了92.4%,吸附量可达94 mg·g^(−1);吸附过程相对符合伪一级动力学方程,吸附过程偏向于物理吸附;Langmuir等温模型能够更好地反应吸附平衡,吸附以表面单层覆盖为主,最大吸附量为452 mg·g^(−1);在相同条件下,Fe_(3)O_(4)@SA/GO对混合液中亚甲基蓝的吸附效果优于碱性品红;该吸附剂具有良好的循环利用性能,5次脱附循环使用后对亚甲基蓝的吸附率依旧保持在70%以上。以上研究结果可为处理印染废水提供参考。

Fe_(3)O_(4)@SA/GO gel ball was prepared with sodium alginate as skeleton,in combination with Fe_(3)O_(4) and graphene oxide.The magnetic composites were characterized by SEM,FT-IR,XRD and VSM,and its adsorption performance towards methylene blue was also studied.The results showed that many pores was in Fe_(3)O_(4)@SA/GO gel spheres,and the surface of these spheres contained rich oxygen-containing functional groups such as carboxyl and hydroxyl groups.Fe_(3)O_(4)@SA/GO gel spheres had good excellent magnetic and superparamagnetic properties,their saturation magnetization reached 17.88 emu·g^(−1).The adsorption properties and mechanism of methylene blue(MB)from aqueous solution onto the beads were studied.Under the conditions of 25℃,pH=9,100 mg·L^(−1) methylene blue,1 g·L^(−1) adsorbant,the adsorption rate reach 92.4%after 300 min adsorption,and the adsorption capacity reached 94 mg·g^(−1).The adsorption kinetics accorded with pseudo-first order kinetic equation,and the adsorption process preferred to a physical adsorption.The adsorption isotherm data were well fitted to Langmuir model and the adsorption was a mainly monolayer one,the maximum adsorption capacity was 452 mg·g^(−1).Under the same conditions,methylene blue adsorption effect by Fe_(3)O_(4)@SA/GO was superior to basic fuchsin in the dye mixture.The adsorption rate of methylene blue still maintained over 70%after 5 recycling,which indicated that this material had a good recycling ability.The above results can provide a new material and technical reference for the adsorption removal of dyeing wastewater.