固液界面NOM吸附中疏水效应的影响研究  

Hydrophilicity and Hydrophobicity of Adsorption of NOM on Solid-Liquid Interface

作　　者：李孟[1] 吴思[1] 张斌 

机构地区：[1]武汉理工大学土木工程与建筑学院,湖北武汉430070 [2]湖北中碧环保科技有限公司,湖北孝感432000

出　　处：《环境科学与技术》2012年第3期38-42,共5页Environmental Science & Technology

基　　金：国家自然科学基金项目(20876122)

摘　　要：文章以腐殖酸和纳米Fe2O3为对象,着重研究了腐殖酸分子在纳米Fe2O3表面的吸附过程中的疏水效应,借助红外光谱和热重等分析方法研究了腐殖酸吸附前后的疏水性随溶液环境变化的规律。结果表明,当离子强度为0、0.005、0.01和0.05 mol/kg,pH值从7变到12时,纳米Fe2O3吸附溶解性腐殖酸分子后形成的复合体的热失重量随着pH值的升高先减小后增大。当pH值从7升高到10时,亲水性降低,疏水性增强;当pH值从10升高到12时,亲水性增强,疏水性降低。当离子强度为0.001 mol/kg,pH值从7变到12时,复合体的热失重量随着pH值的升高而减小,亲水性降低,疏水性增强。当pH值为定值,离子强度变化时,纳米Fe2O3吸附溶解性腐殖酸分子后形成的复合体的热失重量随着离子强度的增加不断变化,曲线呈现出波动趋势,亲、疏水性在交替变化。红外光谱分析结果说明,对纳米Fe2O3吸附溶解性腐殖酸分子后形成的复合体的亲疏水性起主要影响的官能团可能是亲水性的羟基-OH、羰基C=O和疏水性的CH2烷烃。Aiming to humic acid. and Fe2O3 nanoparticles, hydrophobic effects of humic acid molecules in the adsorption process of Fe2O3nanoparticles were studied, with infrared spectroscopy and thermogravimetric analysis methods, roles of hydrophobic changes with the solution environment before and after humic acid adsorption were discussed. Results showed that when ionic strength was 0, 0.005, 0.01 and 0.05 mol/kg and pH value changed from 7 to 12, ttlermal weight loss of the complex, which formed after nano Fe2O3 adsorbed the dissolved humic acid molecules, decreased at first and then increased as pH value increased. Hydrophilic reduced and hydrophobic enhanced when pH value increased from 7 to 10, while hydrophilic enhanced and hydrophobic reduced when pH value increased from 10 to 12. When ionic strength was 0.001 mol/kg, and pH value changed from 7 to 12, thermal weight loss of the complex decreased as pH value mcreased, which means hydrophilic reduced and hydrophobic enhanced. When pH value was constant and intensity of ionic changed, thermal weight loss of the complex which formed after nano Fe2O3 adsorbed the dissolved humic acid molecules kept changing with the increase of ionic intensity, and the curve showed a fluctuating trend, hydrophilic and hydrophobic changed in the alternating. Infrared spectroscopy results indicated that the functional groups, which play a major role in hydrophilic and hydrophobic of the complex, which formed after nano Fe203 adsorbed the dissolved humic acid molecules may be hydrophilic hydroxyl-OH, carbonyl C=O and hydrophobic alkane CH2.

关 键 词：腐殖酸 纳米Fe2O3 颗粒 热重分析 傅里叶变换红外光谱分析 亲疏水性 

分 类 号：X703[环境科学与工程—环境工程]