【作者】 薛晓博；

【导师】 周岩梅； 许兆义；

【作者基本信息】 北京交通大学 ， 市政工程， 2006， 硕士

【摘要】 系统研究了天然沉积物及其无机矿物组分对中性表面活性剂的吸附性能和吸附机理。选用了四种代表性土壤和三种土壤无机组分（二氧化硅，γ—三氧化二铝和碳酸钙）作为吸附剂，并用X—ray，H—NMR，SEM，电位滴定等先进分析手段对吸附剂的理化性质进行了深入的表征。研究表明四种土壤（S1，S2，S3，S4）对Triton X—100（曲拉通—100，简称为TX）的吸附都能较好的符合Freudlich吸附等温式但其吸附容量差别很大，总有机碳含量高，粘粒和细粉含量高，膨润土含量大的沉积物，吸附容量较大。吸附体系中CaCl₂浓度的增大使S1和S2沉积物吸附容量减少，但一定浓度的CaCl₂溶液却能促进S3和S4沉积物对表面活性剂的吸附，造成这种差异的原因可能在于土壤的有机质含量和疏水性的差别及其表面电性的差异。模型矿物吸附实验表明γ—三氧化二铝和碳酸钙分别在15℃，3.8＜pH＜12.1和25℃，7.7＜pH＜11.7的条件下几乎不吸附TX，这一现象可能是由于三氧化二铝的晶型结构稳定和碳酸钙比表面积较小，从而吸附活性位少造成的。但是二氧化硅在实验条件下对TX有较大的吸附容量，其吸附行为能很好的拟和Freundlich吸附等温式，同时吸附容量随着溶液离子强度、pH值、温度的增加而降低，其中溶液pH值的影响最为显著。热力学计算焓变（～10kJ／mol）和熵值表明二氧化硅对TX的吸附是以物理吸附为主的放热过程。更多还原

【Abstract】 The distribution of Triton X-100 （TX, a typical nonionic surfactant） between sediments/inorganic components samples and water as a function of sediment composition and the adsorption kinetics of TX on to sediments samples were systemically studied. The adsorption capacity does not correlate well with the fraction organic carbon of the sediment, the amount of swelling clay and the hydrophobic index of organic matters may affect the uptake capacity. All the adsorption isotherms are nonlinear. Freudlich isotherms represent the data well. The adsorption kinetics demonstrates there are two different property sorption domains contained in sediments. Addition of CaCl₂ negatively affects adsorption capacity for S1 and S2 for the entire observed concentration rang, yet certain amount of CaCl₂ promotes the affinity for TX for S3 and S4. This discrepancy may result from competitive adsorption and conformational flexibility or rigidity of humic components. And also the adsorption of the widely used nonionic surfactant Triton X-100（TX） onto three model inorganic soil components （silica powder, γ-alumina, and calcite） was investigated in a series of batch experiments in which the aqueous phase equilibrated with solid, under different solution conditions. TX did not show discernable adsorption on γ -alumina （25℃ 3.8<pH<12.1） or calcite （15℃, 7.7<pH<11.7）. Significant and reversible adsorption from solutions was found for silica powder suspensions. The adsorption isotherms obtained for TX uptake on silica powder were best fitted with the Freundlich model. An increase of the ionic strength of the electrolytic solution induced a decrease of the surface concentration of TX on silica powder. Declination of pH value of the electrolyte solution from 9 to 3 considerably increased the adsorbed amount of TX, The adsorption of TX on silica powder decreased with the rise of temperature （15⁴5°C）, indicating that the adsorption is exothermic. The calculated enthalpy of adsorption （¹0kJ/mol） demonstrates that the uptake at solid-liquid equilibrium pH （6.1） was largely due to physisorption.更多还原