Development of Nonaqueous Electrolyte Electrochemical Gas Detector for Unsymmetrical Dimethyl Hydrazine / 航天医学与医学工程

ABSTRACT

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.