Plugging nonporous polyamide membranes for enhanced rejection of small contaminants during advanced wastewater treatment
Plugging nonporous polyamide membranes for enhanced rejection of small contaminants during advanced wastewater treatment
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DOI：
10.1016/j.seppur.2020.117490
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发表时间：
2020-12-15
影响因子：
8.6
通讯作者：
Shintani, Takuji
中科院分区：
文献类型：
--
作者：
Fujioka, Takahiro;Osako, Miyu;Shintani, Takuji
用反渗透（RO）膜去除N-亚硝基二甲胺（NDMA），一种受管制的致癌化学品，是提高再利用饮用水安全性的关键挑战。本研究旨在通过用直链胺、酰胺和环氧化物堵塞RO膜中的纳米孔来实现NDMA和盐的高截留率。用胺或环氧化物堵塞通常导致水渗透率降低和电导率截留率增加。NDMA的截留率随胺的大小线性增加。十二胺堵塞膜对膜生物反应器出水的NDMA截留率可达80%，并能保持8d。相比之下，酰胺或环氧化物塞导致NDMA排斥的仅微小改善。我们推测，胺插头通过静电引力保持在纳米孔中，而酰胺和环氧化物变得容易从纳米孔分离，因为它们仅通过较弱的氢键相互作用结合。这项研究提供了一个了解的堵塞机制，提高NDMA的排斥，并证明了高NDMA排斥使用处理后的废水。
Removing N-nitrosodimethylamine (NDMA), a regulated carcinogenic chemical, with a reverse osmosis (RO) membrane is a key challenge for enhancing the safety of reused potable water. This study aimed to achieve high rejection of NDMA and salts by plugging the nanopores in an RO membrane with linear-chain amines, amides, and epoxides. Plugging with amines or epoxides generally led to a reduction in water permeance and an increase in conductivity rejection. NDMA rejection increased linearly with the size of amines. The RO membrane plugged with dodecylamine exhibited an NDMA rejection of 80% when treating the effluent from a membrane bioreactor, and this performance was maintained for 8 d. In contrast, amide or epoxide plugs resulted in only minor improvements in NDMA rejection. We speculate that the amine plugs remain in the nanopores through electrostatic attractions, whereas amides and epoxides become readily detached from the nanopores because they are only bound through weaker hydrogen-bonding interactions. This study provides an understanding of the plugging mechanism that enhances NDMA rejection and demonstrated high NDMA rejection using treated wastewater.