氨基磺酸型两性表面活性剂在石英砂上的吸附

Adsorption of amino sulfonate amphoteric surfactants on quartz sand

通过静态吸附实验,研究了6种氨基磺酸型两性表面活性剂在石英砂上的吸附,讨论了溶液浓度、表面活性剂疏水基链长、温度和pH对吸附量的影响。结果表明:氨基磺酸盐在石英砂上的吸附具有Langmuir吸附等温式的特点;温度升高使吸附量降低;等温下,溶液浓度低于临界胶束浓度(cmc)时,表面活性剂疏水基链长对吸附量的影响符合Traube规则,溶液浓度高于cmc,疏水基链长增加,吸附平台下降,且疏水基碳数和饱和吸附量Γ_(max)间呈线性关系;溶液pH的变化会导致氨基磺酸型两性表面活性剂和石英砂表面电荷不同,静电作用使吸附量随体系的pH不同而发生变化。

The adsorption of six kinds of amino sulfonate type amphoteric surfactants in aqueous solution on quartz sand was studied through the static adsorption test. Effects of concentration of amino sulfonate amphoteric surfactants in aqueous solution, chain length of hydrophobic group of the amino sulfonate amphoteric surfactants,temperature and pH on amount of adsorption of amino sulfonate amphoteric surfactants on quartz sand were discussed. Results showed that, adsorption of amino sulfonate amphoteric surfactant on quartz sand follows the characteristics of Langmuir adsorption isotherm. Rising of temperature will cause the decline of amount of adsorption. Under isothermal condition, when the surfactant solution concentration is lower than cmc, effect of hydrophobic chain length of the surfactant on the amount of adsorption follows Traube Rule. When the surfactant solution concentration is higher than cmc, increase of hydrophobic chain length will cause the decline of the adsorption plateau. There is linear relationship between the saturated adsorption amount Гmax and the number of carbon atoms in the hydrophobic chain. Change of pH of the surfactant solution will result in the change of electric charge of amino sulfonate surfactant and the quartz sand surface. The electrostatic action will cause the change of amount of adsorption in accordance with the change of the pH of the surfactant solution.