腐殖酸对As(Ⅴ)在覆铁砂介质中吸附行为的影响  

INFlUENCE OF HUMIC ACID ON THE ADSORPTION OF ARSENIC BY SAND COVERED IRON

作　　者：陈锴[1] 李义连[2] 杨国栋[1] 邓天天[1] 梁艳燕[1] 

机构地区：[1]中国地质大学(武汉)研究生院,武汉430074 [2]中国地质大学(武汉)环境学院,武汉430074

出　　处：《环境化学》2010年第2期231-236,共6页Environmental Chemistry

基　　金：国家科技部"863"计划(2007AA06Z333)

摘　　要：对腐殖酸(HA)进行了成分分析及红外表征,并从HA浓度、pH值、As(Ⅴ)初始浓度等方面,研究了HA对As(Ⅴ)在覆铁砂介质中吸附行为的影响.结果表明,随着HA浓度的升高,总砷去除率逐渐降低.当HA浓度增加到25mg.l-1时,与不存在HA条件下相比,总砷去除率降低了12%左右.溶液pH值影响As(Ⅴ)的去除,pH值从6升高到8时,总砷去除率从52.1%降到了39%.其中的作用机理主要是HA与As(Ⅴ)在覆铁砂表面形成竞争吸附,HA争夺了As(Ⅴ)的吸附点位.此外,HA与Fe(Ⅲ)的络合作用也是导致覆铁砂对砷的去除率降低的一个重要原因.This work investigated the influence of HA on the adsorption of As （ Ⅴ） on sand covered iron through the elemental analysis, FTIR and measurement of HA concentration, pH and initial As （ Ⅴ ） concentration. The results indicate that the total arsenic removal rate gradually decreases with the increase of HA concentration. Compared to the situation without HA, when the concentration of HA increased to 25mg· 1-1 the rate of arsenic removal reduced by 12%. pH also affected the removal of arsenic. When pH increased from 6 to 8, the removal rate of arsenic decreased from 52. 1% to 39%. The mechanisms of reaction mainly include ： （ 1 ） HA is preferably to being adsorbed on the surface of sand covered iron compared with As （ Ⅴ ） ; （ 2 ） HA eomplexation with Fe（ Ⅲ） is also an important reason leading to the decrease of arsenic removal rate.

关 键 词：腐殖酸 As(Ⅴ) 覆铁砂 吸附 络合 

分 类 号：X131.2[环境科学与工程—环境科学]