The scarcity of freshwater resources, driven by rapid population growth and industrialization, underscores the urgent need for advanced desalination technologies. This research aims to meet this critical demand by enhancing the performance of polyamide membranes through innovative chemical tuning of the active layer. By strategically using Boc-protected ethylenediamine (EDA), we can precisely control the membrane’s surface properties. One amino group in EDA is protected with a Boc group, allowing the other to participate in the interfacial polymerization (IP) reaction with meta-phenylenediamine (MPD) and trimesoyl chloride (TMC). This inclusion of Boc-protected EDA enables in situ tuning of the active layer chemistry during polymerization. Subsequent removal of the Boc protection generates hydrophilic ammonium groups on the membrane surface, enhancing its desalination capabilities. As a result, three distinct membranes were fabricated and thoroughly characterized: MPD-TMC (control), MPD-TMC-EDA-Boc, and MPD-TMC-EDA-Deboc. At 20 bar and 2000 ppm NaCl feed, the MPD-TMC-EDA-Deboc membrane demonstrated superior desalination performance with a salt rejection of 98 ± 0.5% and a permeate flux of 25 L m⁻² h⁻¹; an increase of 25% compared to the control membrane. For the seawater nanofiltration (NF) permeate with a TDS of 33,700 ppm, a salt rejection of 97% and a permeate flux of 23 L m⁻² h⁻¹ was recorded at 20 bar. The MPD-TMC-EDA-Deboc membrane showed enhanced antifouling performance (95 ± 1% flux recovery) compared to the control MPD-TMC membrane with 93 ± 1% flux recovery. The Boc-protection/deprotection strategy demonstrated the high potential of this approach to significantly enhance the performance of polyamide membranes for desalination applications.

人口快速增长和工业化推动淡水资源稀缺，凸显了对先进海水淡化技术的迫切需求。本研究旨在通过活性层的创新化学调节来增强聚酰胺膜的性能，从而满足这一关键需求。通过策略性地使用 Boc 保护的乙二胺 (EDA)，我们可以精确控制膜的表面特性。 EDA 中的一个氨基被 Boc 基团保护，使另一个氨基参与与间苯二胺 (MPD) 和均苯三甲酰氯 (TMC) 的界面聚合 (IP) 反应。包含 Boc 保护的 EDA 可以在聚合过程中原位调节活性层化学成分。随后去除 Boc 保护会在膜表面产生亲水性铵基团，从而增强其脱盐能力。结果，制造了三种不同的膜并对其进行了彻底的表征：MPD-TMC（对照）、MPD-TMC-EDA-Boc 和 MPD-TMC-EDA-Deboc。在 20 bar 和 2000 ppm NaCl 进料条件下，MPD-TMC-EDA-Deboc 膜表现出卓越的脱盐性能，脱盐率为 98 ± 0.5%，渗透通量为 25 L m ⁻² h ⁻¹ ;与对照膜相比增加了25%。对于 TDS 为 33,700 ppm 的海水纳滤 (NF) 渗透液，在 20 bar 压力下记录的脱盐率为 97%，渗透液通量为 23 L m ⁻² h ⁻¹ 。与具有 93 ± 1% 通量恢复的对照 MPD-TMC 膜相比，MPD-TMC-EDA-Deboc 膜表现出增强的防污性能（95 ± 1% 通量恢复）。 Boc 保护/脱保护策略证明了这种方法在显着提高海水淡化应用中聚酰胺膜性能方面的巨大潜力。