Fe_3O_4/丙烯酸系磁性微球的制备及对Hg~(2+)、Cu~(2+)、Ni~(2+)的吸附

以二乙烯苯为交联剂,采用悬浮聚合法制备了Fe3O4/丙烯酸系磁性吸附剂。聚合条件为:n(丙烯酸甲酯)∶n(二乙烯苯)=17∶1、w(引发剂)=1%、反应温度75~80℃、反应时间6 h。采用X射线衍射(XRD)、红外(IR)、热重分析(TGA)等对其进行了表征,并考察了它对金属离子的吸附性能。结果表明,制备的磁性吸附剂粒径35~55μm,w(Fe3O4)≈18%。吸附容量随pH升高而增加。饱和吸附容量qm(mmol/g)为:Hg2+2.3,Cu2+2.2,N i2+1.1。采用Lagergrent方程计算的吸附速率常数kad(m in-1)分别为:Hg2+0.023,Cu2+0.034,N i2+0.036。吸附剂可用c(H2SO4)=1 mol/L或c(HNO3)=0.5 mol/L再生。

Fe3O4/Acrylate-based Magnetic Microparticles:Preparation and Adsorption Performance Toward Hg2+,Cu2+ and Ni2+

A novel Fe_3O_4/acrylate-based magnetic adsorbent were prepared by suspension polymerization using divinybenzene as a crosslinker.The parameters for polymerization were n(methyl acrylate)∶n(divinybenzene)=17∶1,w(initiator)=1%,reaction temperature 75～80 ℃ and reaction time 6 h.This adsorbent was characterized by XRD,IR,TGA etc.Moreover,the adsorption performance of the adsorbent towards metal ions was investigated.The results showed that the diameter of the magnetic adsorbent was 35～55 μm and the content of Fe_3O_4 was 18%.The adsorption capacity increased with increasing pH.The maximum adsorption capacity(q_m) was 2.3 mmol/g for Hg~(2+),2.2 mmol/g for Cu~(2+) and 1.1 mmol/g for Ni~(2+).The adsorption rate constant calculated by Lagergrent equation was 0.023 min~(-1) for Hg~(2+),0.034 min~(-1) for Cu~(2+) and 0.036 min~(-1) for Ni~(2+).Regeneration of the adsorbent was achieved using 1 mol/L H_2SO_4 or 0.5 mol/L HNO_3.