中文摘要：

N-nitrosodimethylamine (NDMA ) 先锋由一个断然控告的 dimethylamine 组和非极的一半组成，它鼓舞了我们开发一种指向的阳离子交换技术移开 NDMA 先锋。在这研究，我们测试了二位代表性的 NDMA 先锋， dimethylamine (直接存储器存取) 和 ranitidine (RNTD ) 的移动，由强壮的酸的阳离子交换树脂。结果证明 pH 极大地影响了交换效率，与高移动(直接存储器存取 ?>?78% 并且 RNTD ?>?94%) 在 pH 观察了 ?-1 当到先锋的交换能力的臼齿的比率是 4 时。交换顺序如下被获得：Ca ^2?+?>?Mg^2?+?>?RNTD⁺?>?K⁺?>?DMA⁺?>?NH₄⁺?>?Na⁺ 。到 Na ⁺ 的直接存储器存取 ⁺ 的分区系数是 1.41 ? 敢椠 ?楤晳癡 吗？

英文摘要：

N-nitrosodimethylamine（NDMA） precursors consist of a positively charged dimethylamine group and a non-polar moiety, which inspired us to develop a targeted cation exchange technology to remove NDMA precursors. In this study, we tested the removal of two representative NDMA precursors, dimethylamine（DMA） and ranitidine（RNTD）, by strong acidic cation exchange resin. The results showed that pH greatly affected the exchange efficiency, with high removal（DMA 〉 78% and RNTD 〉 94%） observed at pH 〈 pk_a-1 when the molar ratio of exchange capacity to precursor was 4. The exchange order was obtained as follows： Ca~（2＋）〉 Mg~（2＋）〉 RNTD~＋〉 K~＋〉 DMA~＋〉 NH_4~＋〉 Na~＋. The partition coefficient of DMA~＋to Na~＋was 1.41 ± 0.26, while that of RNTD~＋to Na~＋was 12.1 ± 1.9. The pseudo second-order equation fitted the cation exchange kinetics well. Bivalent inorganic cations such as Ca~（2＋）were found to have a notable effect on NA precursor removal in softening column test. Besides DMA and RNTD, cation exchange process also worked well for removing other 7 model NDMA precursors. Overall, NDMA precursor removal can be an added benefit of making use of cation exchange water softening processes.