Reverse osmosis membranes typically suffer compaction during the initial stabilization stage due to the applied hydraulic pressure, altering the desalination performance. The elucidation of the underlying transformations during compaction is key for further development of new membranes and its deployment in real-world scenarios. Hydraulic compaction of amorphous carbon (a-C) based membranes under cross-flow operation for water purification and desalination has been observed experimentally, and analysed employing molecular dynamics simulations. The previous outstanding separation performance for carbon membranes, especially for the nitrogen-containing (a-C:N) type, has been studied during compaction using lab-scale cross-flow desalination membrane systems. Our results indicate that the high-water pressure induces an overall reduction in the interstitial spaces within the a-C structure. Remarkably, the compacted a-C:N membrane exhibits improved performance in salt rejection and water permeability, compared to the a-C based membrane. Our analysis shows that performance improvement can be related to the higher mechanical stability of the carbon structure due to the presence of nitrogen sites, which also promote water diffusion and permeability. These results show that a-C:N based membranes are a feasible alternative to conventional polymeric membranes.

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增强压实碳基反渗透膜的脱盐性能

由于施加的液压，反渗透膜通常在初始稳定阶段受到压实，从而改变了脱盐性能。阐明压实过程中的潜在转变是进一步开发新膜及其在实际场景中部署的关键。已经通过实验观察了在用于水净化和脱盐的错流操作下基于无定形碳 (aC) 的膜的水力压实，并使用分子动力学模拟进行了分析。之前使用实验室规模的错流脱盐膜系统在压实过程中研究了碳膜，尤其是含氮 (aC:N) 类型的出色分离性能。我们的结果表明，高水压会导致 aC 结构内的间隙空间整体减少。值得注意的是，与基于 aC 的膜相比，压实的 aC:N 膜在脱盐率和透水性方面表现出改进的性能。我们的分析表明，由于氮位点的存在，性能改进可能与碳结构更高的机械稳定性有关，这也促进了水的扩散和渗透性。这些结果表明，aC:N 基膜是传统聚合物膜的可行替代品。我们的分析表明，由于氮位点的存在，性能改进可能与碳结构更高的机械稳定性有关，这也促进了水的扩散和渗透性。这些结果表明，aC:N 基膜是传统聚合物膜的可行替代品。我们的分析表明，由于氮位点的存在，性能改进可能与碳结构更高的机械稳定性有关，这也促进了水的扩散和渗透性。这些结果表明，aC:N 基膜是传统聚合物膜的可行替代品。