一种基于电渗析原理的高压微泵-电渗析泵

The project is aiming to develop a novel mode high pressure micropump, electrodialytic pump (EDP). The working principle of EDP is based on electrodialysis technology to produce pure water. The pump is configured as a sandwich-like, a cation exchange membrane (CEM) and an anion exchange membrane (AEM) are isolated by a central channel. Cathode and anode are placed into each outer channel filled with aqueous solution. Under a given current, due to water splitting, hydronium will be generated at the anode, which will migrate into the central channel through the CEM, meanwhile, hydroxide will be generated at the cathode, which will migrate into the central channel through the AEM. The immediate combination of hydronium and hydroxide will produce pure water in the central channel. Because hydronium and hydroxide are highly hydrated ions and they always carry many water molecules, the water molecules they carried are also migrated together with hydronium and hydroxide, leading to much-over-Faraday calculated flow of water (suppose each hydronium or hydroxide carry n water molecules, (n+1)-fold flow can be possibly produced), while the total flow rate will be highly correlated with the applied current. The working principle of EDP completely differs from common piston mechanical pump, and no moving parts are involved (e.g., the piston used in mechanical pump). Thus much less failure rate can be estimated in principle compared with mechanical and electroosmotic pump. A direct application of such EDP is for capillary ion chromatography (CIC) can also be used for other micro-analytical system.

旨在发展一种基于新原理的高压微泵-电渗析泵。基本思路是通过电渗析产生流量与施加电流成正相关的纯水。通过阴、阳离子交换膜构建出类似三明治结构的泵体,两侧为电极通道（充满水溶液），中间为纯水产生通道。在一定电流下，两侧水溶液发生水电解反应，其中阳极区水电解产生的氢离子和阴极区水电解产生的氢氧根离子在电场驱动下分别通过阳离子膜、阴离子膜进入到中间通道快速复合为纯水。由于氢离子和氢氧根离子是高度水合化离子，二者迁移时所携带的水分子将一起迁移，因此理论上会产生远高于法拉第定律理论计算出来的流量（假设每个离子携带n个水分子，可能会产生n+1倍的流量），但总的流速与施加的电流成正相关。该泵工作原理完全不同于传统的机械泵和电渗泵。其泵体无任何移动部件（比如机械泵上的活塞杆），所以原理上故障率会很低。其直接应用对象就是用于毛细管离子色谱系统，同时还可用于其它微分析系统。

发展了一种基于电渗析原理的新模式微泵-电渗析泵。它是通过双极膜-双极膜、或双极膜-阳（或阴）离子交换膜、或阳离子交换膜-阴离子交换膜构建出类似三明治结构的泵体，中间为水溶液产生通道，而两侧为再生液通道。阴阳电极分置于两侧再生液通道中。在电场作用下，从双极膜界面层或再生液通道迁移到中间通道的氢离子和氢氧根离子复合为水。该过程遵循法拉第定律，其流量正比于所施加的电流，非常接近或略高于理论计算值。再生液类型或流速对中间通道产生的水溶液流速无关、而采用阳（或阴）离子膜制作的电渗析泵易引入再生液中的杂质离子，从而导致溶液为酸性。目前电渗析泵所得流量范围为0.1-3 µL/min（并联后可以倍增），波动<3%、电流效率约100%。该模式泵实现了对纳微升流量液流的精准控制。其它优点还包括制作该泵无需特殊原材料，全部来在于商品化产品，这方便于其普及并有望为微纳分析系统提供一种可靠的动力源技术；通过对电渗析泵运行机理的探索还催生了多种相关新技术，包括免脱气电致杂质脱除器、酸、碱或盐电致发生器的及其新应用（比如在线产生测定溶解无机碳的标准碳源、在线酸碱滴定仪）。由于无需脱气，所发展的电渗析设备避免了常规技术对脱气材料的制约，在环境、化工，医药、核电、半导体等领域中痕量无机离子分析具有很好的应用前景。在上述研究中发表第一标注基金号的论文14篇（其中SCI文章11篇（IF>3.0），授权专利3项（一项实现了专利许可转让）。