In order to avoid eutrophication of freshwater systems, regulations all around the world have become increasingly stringent toward the maximum phosphate concentration allowed in wastewater discharges. Traditional phosphate removal methods such as chemical precipitation and enhanced biological phosphorus removal struggle to lower phosphate levels to the new requirements. Hybrid anion exchange nanotechnology (HAIX-Nano) is composed of a selective adsorption material able to remove phosphate down to levels close to zero. Moreover, HAIX-Nano is not affected by intermittent flow and does not produce sludge making it an interesting alternative. The regeneration process of HAIX-Nano typically requires a chemical solution with a high concentration of sodium hydroxide (NaOH) and sodium chloride (NaCl) (2–5% w/w of each). To lower the environmental impact and the operational cost of the technology, this study aims to enhance the HAIX-Nano regeneration efficiency. Therefore, the backbone of HAIX-Nano, which is normally a strong base anionic (SBA) resin, was changed for a weak base anionic (WBA) resin. The resulting material (WBA-2) exhibited a higher adsorption capacity than the traditional version of HAIX-Nano (SBA-1) under the tested conditions, while also showing a much higher regeneration efficiency. For a desorption solution of only 0.4% NaOH and no NaCl, WBA-2 showed an average regeneration efficiency of 78 ± 1% compared to SBA-1 with 24 ± 1%.

为了避免淡水系统的富营养化，世界各地的法规对废水排放中允许的最大磷酸盐浓度变得越来越严格。传统的除磷方法，如化学沉淀和强化生物除磷，努力将磷酸盐水平降低到新的要求。混合阴离子交换纳米技术 (HAIX-Nano) 由一种选择性吸附材料组成，能够将磷酸盐去除到接近零的水平。此外，HAIX-Nano 不受间歇流动的影响，不会产生污泥，使其成为一个有趣的替代方案。HAIX-Nano 的再生过程通常需要含有高浓度氢氧化钠 (NaOH) 和氯化钠 (NaCl)（各为 2-5% w/w）的化学溶液。为了降低该技术的环境影响和运营成本，本研究旨在提高 HAIX-Nano 再生效率。因此，通常是强碱阴离子 (SBA) 树脂的 HAIX-Nano 的主链被更改为弱碱阴离子 (WBA) 树脂。所得材料 (WBA-2) 在测试条件下表现出比传统版本的 HAIX-Nano (SBA-1) 更高的吸附能力，同时也显示出更高的再生效率。对于仅含 0.4% NaOH 且不含 NaCl 的解吸溶液，WBA-2 的平均再生效率为 78 ± 1%，而 SBA-1 的平均再生效率为 24 ± 1%。改为弱碱阴离子 (WBA) 树脂。所得材料 (WBA-2) 在测试条件下表现出比传统版本的 HAIX-Nano (SBA-1) 更高的吸附能力，同时也显示出更高的再生效率。对于仅含 0.4% NaOH 且不含 NaCl 的解吸溶液，WBA-2 的平均再生效率为 78 ± 1%，而 SBA-1 的平均再生效率为 24 ± 1%。已更改为弱碱阴离子 (WBA) 树脂。所得材料 (WBA-2) 在测试条件下表现出比传统版本的 HAIX-Nano (SBA-1) 更高的吸附能力，同时也显示出更高的再生效率。对于仅含 0.4% NaOH 且不含 NaCl 的解吸溶液，WBA-2 的平均再生效率为 78 ± 1%，而 SBA-1 的平均再生效率为 24 ± 1%。