偏二甲肼非水电解液电化学气体检测仪的研制

Development of Nonaqueous Electrolyte Electrochemical Gas Detector for Unsymmetrical Dimethyl Hydrazine

目的研制一种偏二甲肼电化学气体检测仪,以解决偏二甲肼电化学气体检测仪使用寿命短,适用温度范围窄的弊病。方法采用蒸汽压和冰点较低、沸点较高的烷酮类有机物作为溶剂,可溶性导电性盐作为溶质组成非水电解液,贵金属一体化扩散电极作为工作电极、对电极和参考电极,气体扩散电极采用喷涂法自制,以控制电位电解型气体传感器为核心研制偏二甲肼非水电解液电化学气体检测仪。结果对研制的偏二甲肼非水电解液电化学气体检测仪的测试结果表明,检测仪的使用寿命达到2年以上,各项性能指标基本满足技术指标要求,响应时间尚待改进。结论偏二甲肼非水电解液电化学气体检测仪可用于偏二甲肼的泄漏检测。

Objective To develop a nonaqueous electrolyte electrochemical detector in order to solve the problems of shorter average life span and operating temperature range in aqueous electrolyte electrochemical detector for unsymmetrical dimethyl hydrazine（UDMH）. Methods Nonaqueous electrolyte was utilized in this kind of electrochemical detector comprised of n-mehyl-2-pyrrolidone with conductive compatible salts,such as tetrabutyl ammonium tetrafluoroborate,which had much lower evaporating pressure and freezing point than aqueous electrolyte ones. Three-electrode potential electrochemical system was also used, composing a sensing electrode,a counter electrode and a reference electrode. The three electrodes were all teflon-bonded diffusion electrodes which were prepared by spraying the noble metal catalyst dispersion onto the Teflon film. Results The experiment result showed that the average life span could be over two years compared with the aqueous electrolyte electrochemical detector of one year life span. Operating temperature range was expanded to - 20 ℃ ～＋ 40 ℃. However,the response time was nearly five minutes. Conclusion The detector can be used for leakage checking in the places where a large quantities of UDMH are used or stored.