亚甲基蓝在海洋沉积物上的吸附行为

Sorption Behavior of Methylene Blue on Marine Sediments

本文对常用的染料亚甲基蓝(MB)在海洋沉积物上的吸附行为进行了研究,发现它的吸附机理主要是在沉积物上的表面吸附和微孔作用,吸附与黏土矿物的含量有一定的相关性。在实验浓度范围内,MB在3种不同处理方式沉积物上的吸附行为都可以用Freundlich等温式来描述。通过改变吸附条件发现,随着盐度的增加,吸附能力减小,而温度的改变,对吸附能力的影响并不明显。此外,通过向体系中加入不同表面活性剂来模拟双溶质体系的方法,对MB与表面活性剂的竞争吸附行为进行了研究。结果发现在2种介质中,吐温20(Tween20)的加入对吸附的影响均不大;十六烷基三甲基溴化铵(CTAB)的加入使MB的吸附能力减弱,在蒸馏水中抑制作用更加明显;在海水中,十二烷基苯磺酸钠(SDBS)对吸附有抑制作用,而在蒸馏水中,SDBS却对吸附起到促进作用。

The sorption behavior of methylene blue（MB） on marine sediments was investigated.It was found that surface adsorption and micropore effect played an important role on the sorption mechanism of MB,and the content of clay minerals had a certain correlation with the adsorption.Sorption behavior of MB on different treatment sediments was fit with Freundlich isotherms very well over the concentration range.When the experimental condition was changed,it was found that the sorption was favorably influenced by decreasing ionic strength of seawater,and temperature made no obvious impact on adsorption capacity.Furthermore,different surfactants were added to simulate double-solute system for the study of competitive adsorption behavior of MB with other organic substances.The result showed that the adsorption of MB was not influenced by adding Tween20 in different media.The adsorption of MB decreased with increasing the concentration of hexadecyltrimethylammonium bromide（CTAB）,and the extent of effect was more evident in deionized water.In nature seawater,sodium dodecylbenzenesulfonate（SDBS） had a negative effect on adsorption,while SDBS had a positive effect in DW.