Abstract: This paper reviewed the methods of phosphoric acid extractive distillation，reactive distillation and electro-electrodialysis pre-concentration for HI concentration and separation in iodine-sulfur thermochemical cycle. The mechanisms，energy efficiency，advantages，and prospects of these methods were discussed. Phosphoric acid extractive distillation was developed earlier than the other methods，however，its complicated operational conditions prevented the improvement of energy efficiency of this method. The high integrity level of reactive distillation could improve thermal efficiency dramatically，but experimental research concerning the practical application is very limited due to its rigorous operational conditions. Electro-electrodialysis for HI pre-concentration is a promising method because of its easy operation，mild conditions and high efficiency. Future research on this method should be focused on scale-up，modularization and the efficient cooperation with HI distillation.

Key words: iodine-sulfur cycle, HI concentration, phosphoric acid extractive distillation, reactive distillation, electro-electrodialysis

摘要： 综述了碘硫循环制氢中用于HI浓缩分离的3种主要技术路线，即磷酸萃取精馏、反应精馏以及电解电渗析预浓缩-精馏的研究进展，对各路线的过程原理、操作流程、能量利用效率等方面进行了讨论，在此基础上对比了其各自的优点和不足之处，并对其应用前景进行了展望。其中，磷酸萃取精馏开发最早，相对成熟，但操作流程复杂，运行效率需进一步提升；反应精馏流程有望以高集成度取得高效率，但所需条件非常苛刻，其设备开发、工艺实验等工作亟待展开；近年来发展较快的电解电渗析预浓缩-精馏工艺由于具有操作简单，条件温和，浓缩效率高等优点而具有较好的应用前景，其进一步工艺放大、模块化以及与精馏的高效协同等都是未来研究的重点和难点。

关键词: 碘硫循环, 碘化氢浓缩, 磷酸萃取精馏, 反应精馏, 电解-电渗析