The removal of silver nanoparticle by titanium tetrachloride and modified sodium alginate composite coagulants: floc properties, membrane fouling, and floc recycle
The removal of silver nanoparticle by titanium tetrachloride and modified sodium alginate composite coagulants: floc properties, membrane fouling, and floc recycle
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DOI：
10.1007/s11356-018-2240-7
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发表时间：
2018-05
影响因子：
5.8
通讯作者：
Ziyang Wang;Yan Wang;Cong Yu;Yanxia Zhao;Meixia Fan;B. Gao
中科院分区：
文献类型：
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作者：
Ziyang Wang;Yan Wang;Cong Yu;Yanxia Zhao;Meixia Fan;B. Gao
将改性海藻酸钠(MSA)与TiCl4复合，采用混凝-超滤工艺处理合成银纳米颗粒(AgNPs)水。采用激光衍射仪和超滤污染模型研究了TiCl4和MSA复合混凝剂(TiCl4+MSA)的絮凝性能和膜污染情况。通过X射线衍射和光催化实验对含AgNP絮体的回收利用进行了评价。结果表明，在最佳条件下(pH = 为5， = 投加量为12 mg TiCl4/L)，TiCl4+MSA的混凝效果优于单独使用TiCl4，AgNP和DOC的去除率分别达到97%和59%。TiCl4+MSA比TiCl4和TiCl4+SA复合混凝剂(TiCl4+SA)产生的絮体更大、更疏松，有利于抑制后续的膜污染。在最佳混凝条件下，TiCl4+MSA的强附着外部污垢阻力(Ref-S)和可逆内污垢阻力(Rif-r)仅为TiCl4的43%和39.2%。此外，所采用的AgCl-TiO2可以从含AgNP的絮体中回收。MSA可促进二氧化钛锐钛矿的形成。这为银纳米粒子的回收利用提供了一条可能的途径。
In this study, a modified sodium alginate (MSA) composited with TiCl4was used to treat the synthetic Ag nanoparticles (AgNPs) water in coagulation-ultrafiltration process. The floc properties and membrane fouling of TiCl4and MSA composite coagulants (TiCl4+ MSA) were investigated by a laser diffraction instrument and ultrafiltration fouling model. The recycle of the AgNP-containing flocs was evaluated by XRD and photocatalytic experiments. The results showed that TiCl4+ MSA could achieve better coagulation performance than TiCl4alone with AgNP and DOC removal up to 97 and 59% at the optimum condition (pH = 5 and dosage = 12 mg TiCl4/L). TiCl4+ MSA produced larger and looser flocs than TiCl4and TiCl4+ SA composite coagulant (TiCl4+ SA), which was benefit for the inhibition of subsequence membrane fouling. The strongly attached external fouling resistance (Ref-s) and the reversible internal fouling resistance (Rif-r)of TiCl4+ MSA were only 43 and 39.2% of those achieved by TiCl4at the optimal coagulation condition. Besides, the adopted AgCl-TiO2could be recycled from AgNP-containing flocs. And MSA could promote the form of TiO2anatase. It gives us a possible way for silver nanoparticle recycle.