水溶性腐植酸对石英砂负载氧化铁吸附苯并三唑的影响

水溶性腐植酸(DHA)对环境中污染物的吸附有重要影响。通过批实验研究了阳离子类型、DHA浓度等因素对石英砂负载氧化铁吸附DHA和苯并三唑(BTA)的影响。结果表明:在溶液pH为6.0时, 静电作用在石英砂负载氧化铁吸附DHA的过程中起重要作用, Freundlich模型能很好地描述石英砂负载氧化铁对BTA的吸附;DHA对石英砂负载氧化铁吸附BTA的影响程度与DHA浓度和电解质类型有关, 当DHA浓度在0 ~15.68 mg·L^-1范围时, 在以0.01 mol·L^-1 CaCl₂为背景电解质的溶液中, DHA浓度越大, 其促进BTA吸附越明显;DHA通过累积吸附作用, 促进石英砂负载氧化铁对BTA的吸附;在不同的电解质溶液中, 石英砂负载氧化铁对DHA的吸附量不同, 从而对石英砂负载氧化铁吸附BTA的影响也不同。

Effect of Dissolvable Humic Acid on Benzotriazole Sorption by Iron Oxide Coated Quartz Sands

Dissolvable humic acid(DHA) plays an important role in sorption of pollutants in the environment. The effects of cation type and DHA concentration on sorption of DHA and benzotriazole(BTA) on iron oxide coated quartz sands(IOCQS) were studied using batch experiments. At the solution pH 6.0, electrostatic interaction plays an important role in the sorption of DHA by IOCQS. The isotherms of BTA sorption by IOCQS could be well described by Freundlich model. The effect of DHA on sorption of BTA was strongly determined by DHA concentration and electrolyte type. At 0~15.68 mg·L^-1 of DHA concentration, DHA enhanced sorption of BTA on IOCQS in 0.01 mol·L^-1 CaCl₂ solution. Such enhancement was mainly resulted from cumulative sorption. Under different background electrolytes, the amount of adsorbed DHA was different, and the effect of DHA on BTA sorption by IOCQS was consequently different.