Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Ecotoxicol Environ Saf. 2018 Jun 15;154:84-91. doi: 10.1016/j.ecoenv.2018.01.032. Epub 2018 Feb 22.
Aniline aerofloat (AAF), a high-toxic organic flotation reagent, is widely used in mineral processing industry. However, little information on its environmental fate is available. AAF sorption to four types of agricultural soils at low concentrations (1-10 mg/L) was investigated using batch experiments. AAF sorption kinetics involved both boundary layer diffusion and intraparticle diffusion, following pseudo-second-order kinetics with equilibrium time within 120 min. Both Langmuir and Freundlich models fitted well the AAF sorption with the former better. Sorption of AAF to soils was a spontaneous and favorable physical sorption that was controlled by ion bridge effect and hydrophobic interaction that was related to van der Waals force and π-π coordination based on FTIR analyses. AAF sorption was remarkably affected by soil constituents, positively correlating with the contents of organic matter and clay. The relatively higher logK values (3.53-4.66) of AAF at environmental concentrations (1-5 mg/L) imply that soils are serving as a sink of AAF from beneficiation wastewater, posing great potential risks to environment and human health.
偶氮甲酰胺(AAF)是一种高毒性的有机浮选试剂,广泛应用于矿物加工行业。然而,关于其环境归宿的信息很少。本研究采用批量实验,研究了低浓度(1-10mg/L)下偶氮甲酰胺在四种农业土壤中的吸附情况。偶氮甲酰胺的吸附动力学涉及边界层扩散和颗粒内扩散,符合准二级动力学,平衡时间在 120min 内。Langmuir 和 Freundlich 模型均能很好地拟合偶氮甲酰胺的吸附,前者拟合更好。偶氮甲酰胺在土壤中的吸附是一种自发和有利的物理吸附,受离子桥效应和疏水相互作用控制,这与基于 FTIR 分析的范德华力和π-π配位有关。土壤成分对偶氮甲酰胺的吸附有显著影响,与有机质和粘土的含量呈正相关。在环境浓度(1-5mg/L)下,偶氮甲酰胺的相对较高的 logK 值(3.53-4.66)表明,土壤是选矿废水中偶氮甲酰胺的汇,对环境和人类健康构成了巨大的潜在风险。