Abstract Sorption is an important means for pollutant migration in aquatic environments and an important mechanism of pollutant transfer and transformation. Thus, understanding the sorption/desorption of organic pollutants in an aquatic environment is vital to predicting pollutant fate. In this study, Bisphenol A (BPA) was selected as the target pollutant for an investigation of sorption characteristics on three sediments in the Lanzhou section of the Yellow River, with examination of sorption thermodynamic parameters and the effects of temperature, pH, and sediment particle size. Sorption is described well by the pseudo-second-order kinetic model, occurring at two stages, fast (0–6 h) and slow (6–16 h), with equilibrium reached within 16 h. The results suggested that the intraparticle diffusion was dominant in the sorption process. Sorption thermodynamics was nonlinear, fitting well with the Freundlich isotherm model. Physical sorption is the likely mechanism, combining the contributions of π–π interaction and hydrophobic interaction. Thermodynamic parameter analysis showed that Gibbs free energy, enthalpy, and entropy were less than zero, showing that it is spontaneous, exothermic, and chaos-decreasing. Among tested influence parameters, pH values, ionic strengths, temperatures, and particle sizes were found to considerably influence the sorption of BPA. Sorption capacity decreased as sediment particle size increased and as pH increased. Sorption capacity increased with increasing Ca 2+ and decreased with increasing Na + . The results have important implications regarding the impact of sorption/desorption at different environmental factors and fate of BPA in Yellow River.

中文翻译：

---

黄河双酚A：吸附特性及影响因素

摘要 吸附是污染物在水环境中迁移的重要手段，是污染物迁移转化的重要机制。因此，了解水生环境中有机污染物的吸附/解吸对于预测污染物归宿至关重要。本研究选择双酚 A (BPA) 作为目标污染物，研究了黄河兰州段三种沉积物的吸附特性，考察了吸附热力学参数以及温度、pH 和沉积物颗粒的影响尺寸。吸附通过伪二级动力学模型很好地描述，发生在两个阶段，快（0-6 小时）和慢（6-16 小时），在 16 小时内达到平衡。结果表明，颗粒内扩散在吸附过程中占主导地位。吸附热力学是非线性的，与 Freundlich 等温线模型非常吻合。物理吸附是可能的机制，结合了 π-π 相互作用和疏水相互作用的贡献。热力学参数分析表明，吉布斯自由能、焓、熵均小于零，表明它是自发的、放热的、混沌递减的。在测试的影响参数中，发现 pH 值、离子强度、温度和粒径对 BPA 的吸附有很大影响。随着沉积物粒径的增加和 pH 值的增加，吸附能力降低。吸附能力随着Ca 2+ 的增加而增加，随着Na + 的增加而减少。结果对吸附/解吸在不同环境因素下的影响和黄河双酚A的归宿具有重要意义。