Advances in electrochemical synthesis of ammonia

doi:10.11949/j.issn.0438-1157.20170085

Abstract

Abstract:

Ammonia (NH₃) is one of the most widely produced chemicals worldwide with a key role in the growth of global economy. Traditional ammonia synthesis by the Haber-Bosch process runs at high temperature and pressure with low hydrogen conversion, high energy consumption and severe environmental pollution. Electrochemical synthesis of ammonia has been immensely studied as it is operated at ambient temperature and pressure. The electrochemical synthesis has been improved via choosing electrolyte systems, preparing electrodes and electrocatalysts, and constructing highly efficient and stable electrochemical cells. This review summarized recent progress of electrochemical ammonia synthesis in five electrolyte systems including liquid electrolyte, proton conductor ceramic membrane, molten salts, a composite electrolyte of molten salts and ceramic membrane, and organic proton exchange membrane. Mechanism of electrochemical ammonia production, current technical status, major challenges and future directions were discussed.

Key words: electrochemistry, synthesis of ammonia, electrolyte, electrode, catalysis

摘要：

氨是世界上产量最大的化工产品之一，在全球经济中占有重要地位。传统的Haber-Bosch合成氨工艺需要在高温高压下进行，并且氢的平衡转化率低、能耗高、污染严重。电化学方法因可实现氨的常温常压合成而成为备受关注的研究领域。电化学合成氨的关键在于选择合适的电解质、制备电极及电催化剂，并将其有机组合在一起构建成高效稳定的电解池体系。综述了液体电解质、质子导体陶瓷膜电解质、熔盐电解质、陶瓷膜-熔盐复合电解质和有机质子交换膜电解质5类电解质体系的电化学合成氨的研究进展，介绍了相应的电化学合成氨原理，分析了技术发展现状和存在的问题，展望了未来研究的发展方向。

关键词: 电化学, 合成氨, 电解质, 电极, 催化

CLC Number:

O646.5

LIU Shuzhi, HAN Wei, LIU Xianjun, CUI Baochen. Advances in electrochemical synthesis of ammonia[J]. CIESC Journal, 2017, 68(7): 2621-2630.

刘淑芝, 韩伟, 刘先军, 崔宝臣. 电化学合成氨研究进展[J]. 化工学报, 2017, 68(7): 2621-2630.

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