Department of Chemistry, Queen's University at Kingston, Kingston, ON, Canada K7L 3N6.
Department of Chemistry, Queen's University at Kingston, Kingston, ON, Canada K7L 3N6.
Ecotoxicol Environ Saf. 2021 Jan 15;208:111635. doi: 10.1016/j.ecoenv.2020.111635. Epub 2020 Nov 13.
Micellar enhanced ultra-filtration (MEUF) is a modified ultrafiltration (UF) method that can remove small molecules that are not effectively removed by UF alone. In this work we used a similar semi-equilibrium dialysis (SED) method to characterize two anionic surfactants, sodium dodecyl sulfate (SDS) and sodium laurate (SOL), as MEUF candidates to remove several polycyclic aromatic hydrocarbon (PAH) compounds. These anionic surfactants have low toxicity and are more biodegradable compared to the fairly toxic and persistent cetyltrimethylammonium bromide (CTABr) and similar cationic surfactants, which is important as MEUF surfactants may be present in the treated effluent. The log binding constants (Log K) of the PAHs naphthalene, phenanthrene, pyrene and fluorene to SDS ranged from 3.07 to 4.48, which compared well with the previous results for CTABr and indicated that SDS is an excellent candidate for MEUF. The log binding constants for the same PAHs with SOL micelles ranged from 2.11 to 3.53, which suggested that SOL might be adequate for stronger-binding PAH like pyrene and fluorene but less suitable for naphthalene and phenanthrene. The results demonstrated a strong correlation between the Log K with one micelle type and the Log K with the other, suggesting a common set of properties and interactions are responsible for the binding. Similar to the previous results for CTABr, a significant correlation between Log K and Log K values indicates that hydrophobic character is the main driving force for PAH binding with these anionic micelles. This may also be useful for predicting MEUF performance for various compound/surfactant combinations where Log K is not known.
胶束增强超滤（MEUF）是一种改良的超滤（UF）方法，可去除单独超滤无法有效去除的小分子。在这项工作中，我们使用了类似的半平衡透析（SED）方法来表征两种阴离子表面活性剂，十二烷基硫酸钠（SDS）和月桂酸钠（SOL），作为 MEUF 候选物，以去除几种多环芳烃（PAH）化合物。与毒性相当大且持久性较强的十六烷基三甲基溴化铵（CTABr）和类似的阳离子表面活性剂相比，这些阴离子表面活性剂毒性较低且更易生物降解，这一点很重要，因为 MEUF 表面活性剂可能存在于处理后的废水中。PAHs 萘、菲、芘和芴与 SDS 的结合常数（Log K）范围为 3.07 至 4.48，与 CTABr 的先前结果相当，表明 SDS 是 MEUF 的理想候选物。对于具有 SOL 胶束的相同 PAHs，Log K 的范围为 2.11 至 3.53，这表明 SOL 可能适用于与强结合的 PAH 如芘和芴，但对于萘和菲则不太适用。结果表明，与一种胶束类型的 Log K 之间存在很强的相关性，与另一种胶束类型的 Log K 之间也存在很强的相关性，这表明一组共同的性质和相互作用负责结合。与 CTABr 的先前结果类似，Log K 和 Log K 值之间存在显著相关性，表明疏水性是 PAH 与这些阴离子胶束结合的主要驱动力。这对于预测各种化合物/表面活性剂组合的 MEUF 性能也可能有用，其中 Log K 未知。
