Abstract This paper describes a novel approach to fabricate a multilayer composite membrane for recovering and enriching helium from natural gas processing using commercially available thin-film composite polyamide reverse osmosis (RO) membranes. The RO membranes, which are defective in a dry state, were caulked with different polymeric materials to seal the defects; then, the permeation and separation properties were characterized using pure and mixed gases. A benchmark (Nafion®−117) membrane was selected for its superior selectivity towards helium over carbon dioxide, and the performances of the caulked RO membranes were compared. The experimental results show that the ideal selectivity of He/CO2 in the pure gas tests is in the range 20–55, while the permeance of helium is in the range 8–40 GPU depending on the caulking material. A quaternary mixture of CH4, N2, CO2, and He was used to evaluate the separation performance of the novel membrane, which was compared with that of the benchmark membrane. This study confirms that the proposed novel approach for membrane fabrication is technically practical to recover and enrich helium from CO2-containing natural gas streams.

中文翻译：

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用于富氦的多层薄膜复合膜

摘要 本文描述了一种使用市售薄膜复合聚酰胺反渗透 (RO) 膜制造多层复合膜的新方法，用于从天然气加工中回收和富集氦气。RO膜在干燥状态下有缺陷，用不同的聚合物材料填塞以密封缺陷；然后，使用纯气体和混合气体表征渗透和分离特性。选择基准 (Nafion®-117) 膜是因为它对氦气的选择性优于二氧化碳，并比较了嵌缝 RO 膜的性能。实验结果表明，纯气体测试中理想的 He/CO2 选择性在 20-55 范围内，而氦气渗透率在 8-40 GPU 范围内，具体取决于填缝材料。使用 CH4、N2、CO2 和 He 的四元混合物来评估新型膜的分离性能，并与基准膜进行比较。该研究证实，所提出的膜制造新方法在从含 CO2 的天然气流中回收和富集氦气在技术上是可行的。