磁性氧化石墨烯/聚丙烯胺盐酸盐微胶囊在染料吸附中的应用

针对染整过程中产生的废水量较大,对环境造成污染的问题,通过层层自组装(LBL)的方法,利用带有相反电荷的四氧化三铁-氧化石墨烯(Fe₃O₄-GO)和聚丙烯胺盐酸盐(PAH)制备磁性微胶囊,用于染色废水的吸附研究。分析了Fe₃O₄-GO及(PAH/Fe₃O₄-GO)_n微胶囊的形貌与化学结构。考察了(PAH/Fe₃O₄-GO)₂微胶囊对阳离子染料亚甲基蓝的吸附行为及吸附机制。结果表明:当染料的质量浓度为0.2~3.0 mg/mL时,(PAH/Fe₃O₄-GO)₂微胶囊对染料的吸附在20 min内可达到最大吸附量;在25 ℃,pH=12条件下,(PAH/Fe₃O₄-GO)₂对染料的吸附率可达96.5%;Langmuir吸附等温线模型和准二级动力学模型能更好地描述(PAH/Fe₃O₄-GO)₂微胶囊对亚甲基蓝的吸附过程,计算得到理论最大吸附量为219.996 mg/g。

Application of magnetic-graphene oxide/poly(allylamine hydrochloride) microcapsules for adsorption of dyes

Facing the problem that printing and dyeing wastewater pollutes environment, this paper reports on hybrid magnetic microcapsules with Fe₃O₄-graphene oxide (Fe₃O₄-GO) and poly(allylamine hydrochloride) (PAH) for purifying and cleaning the wastewater during dyeing processes. These microcapsules were made through layer-by-layer (LBL) self-assembly due to the opposite charges of Fe₃O₄-GO and PAH. The structure and morphology of Fe₃O₄-GO and (PAH/Fe₃O₄-GO)_n were characterized. Cationic methylene blue was then used to study the adsorption behaviour and mechanism of magnetic microcapsules. When methylene blue dye (0.2-3.0 mg/mL) was absorbed for 20 minutes by microcapsules, the adsorption reached maximum. Moreover, the absorption reaches maximum value at pH of 12 with an adsorption rate of 96.5%. The pseudo-second-order adsorption kinetic and Langmuir adsorption isothermal model are more suitable for describing the adsorption process of methylene blue on magnetic (PAH/Fe₃O₄-GO)₂ microcapsules, with the theoretical maximum adsorption of 219.996 mg/g.