Department of Environmental Engineering Sciences, Engineering School of Sustainable Infrastructure & Environment, University of Florida, P.O. Box 116450, Gainesville, FL 32611-6450, USA.
Water Res. 2013 Nov 1;47(17):6432-44. doi: 10.1016/j.watres.2013.08.015. Epub 2013 Aug 27.
One of the major sources of pharmaceuticals in the environment is wastewater effluent of which human urine contributes the majority of pharmaceuticals. Urine source separation has the potential to isolate pharmaceuticals at a higher concentration for efficient removal as well as produce a nutrient byproduct. This research investigated the efficacy of using strong-base anion exchange polymer resins to remove the widely detected and abundant pharmaceutical, diclofenac, from synthetic human urine under fresh and ureolyzed conditions. The majority of experiments were conducted using a strong-base, macroporous, polystyrene resin (Purolite A520E). Ion-exchange followed a two-step removal rate with rapid removal in 1 h and equilibrium removal in 24 h. Diclofenac removal was >90% at a resin dose of 8 mL/L in both fresh and ureolyzed urine. Sorption of diclofenac onto A520E resin was concurrent with desorption of an equivalent amount of chloride, which indicates the ion-exchange mechanism is occurring. The presence of competing ions such as phosphate and citrate did not significantly impact diclofenac removal. Comparisons of three polystyrene resins (A520E, Dowex 22, Dowex Marathon 11) as well as one polyacrylic resin (IRA958) were conducted to determine the major interactions between anion exchange resin and diclofenac. The results showed that polystyrene resins provide the highest level of diclofenac removal due to electrostatic interactions between quaternary ammonium functional groups of resin and carboxylic acid of diclofenac and non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Diclofenac was effectively desorbed from A520E resin using a regeneration solution that contained 4.5% (m/m) NaCl in an equal-volume mixture of methanol and water. The greater regeneration efficiency of the NaCl/methanol-water mixture over the aqueous NaCl solution supports the importance of non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Experiments with ketoprofen, in addition to diclofenac, suggest that polystyrene anion exchange resins can be used to selectively remove other acidic pharmaceuticals from urine.
环境中药物的主要来源之一是废水污水，其中人类尿液是大多数药物的主要来源。尿液源分离有潜力将药物浓缩，以更有效地去除，同时产生一种营养副产物。本研究调查了使用强碱阴离子交换聚合物树脂从新鲜尿液和尿素分解尿液中去除广泛检测到的丰富药物双氯芬酸的效果。大多数实验使用强碱、大孔、聚苯乙烯树脂（Purolite A520E）进行。离子交换遵循两步去除率，在 1 小时内快速去除，在 24 小时内达到平衡去除。在新鲜和尿素分解尿液中，树脂剂量为 8 毫升/升时，双氯芬酸的去除率>90%。双氯芬酸在 A520E 树脂上的吸附与等当量的氯化物的解吸同时发生，这表明离子交换机制正在发生。磷酸根和柠檬酸盐等竞争离子的存在并没有显著影响双氯芬酸的去除。比较了三种聚苯乙烯树脂（A520E、Dowex 22、Dowex Marathon 11）和一种聚丙烯酸树脂（IRA958），以确定阴离子交换树脂与双氯芬酸之间的主要相互作用。结果表明，由于树脂的季铵官能团与双氯芬酸的羧酸基之间的静电相互作用以及树脂基质与双氯芬酸的苯环之间的非静电相互作用，聚苯乙烯树脂提供了最高水平的双氯芬酸去除率。使用含有 4.5%（m/m）NaCl 的再生溶液，以甲醇和水的等体积混合物，从 A520E 树脂中有效地解吸双氯芬酸。NaCl/甲醇-水溶液的再生效率大于水溶液的 NaCl 溶液，这支持了树脂基质与双氯芬酸的苯环之间的非静电相互作用的重要性。除双氯芬酸外，酮洛芬的实验表明，聚苯乙烯阴离子交换树脂可用于从尿液中选择性去除其他酸性药物。
