天然有机质在生物炭负载纳米镍铁降解十溴联苯醚过程中的影响作用机理辨识

发布时间：2018-04-10 05:27

本文选题：天然有机质　切入点：纳米零价铁　出处：《化学学报》2017年06期

【摘要】：天然有机质(NOM)对纳米铁基材料去除污染物过程中的影响作用机理仍存争议.本工作选取腐殖酸(HA)作为NOM的代表物,研究了HA对生物炭负载纳米镍铁(BC@Ni/Fe)降解十溴联苯醚(BDE209)的动力学影响,结果表明HA对BC@Ni/Fe降解BDE209产生抑制作用,且随着HA浓度的升高,抑制作用越显著.通过HA与BC@Ni/Fe相互作用实验发现,HA能够快速地被BC@Ni/Fe吸附;通过HA对BC@Ni/Fe的Zeta电位和沉降影响实验发现,随着HA浓度的升高可有效提高BC@Ni/Fe的稳定性以及表面电荷,这表明HA不是通过影响BC@Ni/Fe颗粒的性能对BC@Ni/Fe去除BDE209产生抑制作用的.BC@Ni/Fe的腐蚀能力随着HA浓度的升高而降低,这与HA对BC@Ni/Fe去除BDE209反应活性影响成正相关关系.HA中具有电子传递作用的典型醌类化合物2-羟基-1,4-萘醌(Lawsone)和蒽醌-2,6-磺酸钠(AQDS),在反应过程中并没有起到电子传递作用促进反应进行,反而对BC@Ni/Fe去除BDE209起抑制作用.结合BDE209和HA之间的竞争吸附实验发现,HA抑制BC@Ni/Fe反应活性的主导原因是HA优先于BDE209被BC@Ni/Fe吸附,HA包覆于BC@Ni/Fe颗粒表面占据了活性位点,阻碍BC@Ni/Fe与H_2O的接触,减少了Fe0的腐蚀,从而抑制了BC@Ni/Fe对BDE209的降解.
[Abstract]:The mechanism of the effect of natural organic matter (NOM) on the removal of pollutants from nanocrystalline iron based materials is still controversial.The effect of HA on the degradation of decabromodiphenyl ether (BDE209) by nano-Ni / Fe supported on biological carbon was studied. The results showed that HA inhibited the degradation of BDE209 by BC@Ni/Fe, and with the increase of HA concentration, the effect of HA on the degradation of BDE209 was studied.The more significant the inhibitory effect was.Through the experiment of the interaction between HA and BC@Ni/Fe, it was found that the HA could be adsorbed by BC@Ni/Fe quickly, and the effect of HA on Zeta potential and sedimentation of BC@Ni/Fe was found to increase the stability and surface charge of BC@Ni/Fe with the increase of HA concentration.This indicates that the corrosion resistance of BC@Ni/Fe to BDE209 removal is decreased with the increase of HA concentration, which is not due to the effect of HA on the performance of BC@Ni/Fe particles.The effect of HA on the activity of BDE209 removal from BC@Ni/Fe was positively correlated. The typical quinone compounds 2-hydroxy-1- (4-naphthoquinone) and anthraquinone (-2O6-sulfonate) in HA did not play an electron transfer role in the process of the reaction to facilitate the reaction, and the effect of HA on the activity of BDE209 removal was positively correlated with the effect of HA on the activity of BDE209 removal.On the contrary, it inhibited the removal of BDE209 by BC@Ni/Fe.In combination with the competitive adsorption experiments between BDE209 and HA, it was found that the main reason for the inhibition of BC@Ni/Fe reaction activity was that HA was preferentially coated by BC@Ni/Fe on the surface of BC@Ni/Fe particles and occupied the active sites, which hindered the contact between BC@Ni/Fe and H _ 2O and reduced the corrosion of Fe0.Thus, the degradation of BDE209 by BC@Ni/Fe was inhibited.
【作者单位】：华南师范大学化学与环境学院;广东省水环境生态治理与修复工程技术研究中心;广东高校城市水环境生态治理与修复工程技术研究中心;
【基金】：NSFC-广东联合基金(No.U1401235)资助~~
【分类号】：TB34;X592

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