水环境中六溴环十二烷的光降解研究

Abstract

<span>研究了模拟太阳光和500W紫外灯两种光源下,水中六溴环十二烷(HBCDs)的光降解动力学,同时还研究了紫外光下pH、腐植酸(HA)、Fe(Ⅲ)、过氧化氢(H2O2)和二氧化钛(TiO2)纳米颗粒对HBCDs降解效率的影响.研究表明,在模拟太阳光和紫外光照下,HBCDs的降解速率常数和半衰期分别是7.5&times;10-3h-1、0.11h-1和92h、6.5h.在紫外光下,溶液的初始pH对HBCDs的光降解几乎没有影响.而HA、Fe(Ⅲ)和H2O2对HBCDs的光降解均有一定程度的促进作用,但作用较弱,促进作用由大到小的顺序为HA&gt;Fe(Ⅲ)&gt;H2O2.而TiO2纳米颗粒对HBCDs光降解的催化作用则非常显著.结果表明,直接光解是HBCDs光解的主要途径.在TiO2纳米颗粒的催化下,自然水体中HBCDs可在紫外光照射下快速而有效地去除.&nbsp;</span><span><a id="ChDivSummaryMore" style="display: none"><font color="#002b82">更多</font></a><a id="ChDivSummaryReset" style="display: none"><font color="#002b82">还原</font></a></span><span>The degradation kinetics of HBCDs under simulated sunlight and UV lamp(500 W) were studied.And the effect of initial pH,humic acid(HA),Fe(Ⅲ),peroxide hydrogen(H2O2) and TiO2 nanoparticles on the photolysis of HBCDs in water under UV lamp was also examined.It was found that the rate constant and half-life under simulated sunlight and UV lamp were 7.5&times;10-3 h-1,0.11 h-1,92 h and 6.5 h,respectively.Under UV lamp,the effect of initial solution pH was minimal,and the effect of HA,Fe(Ⅲ) and H2O2 was no</span