Study on Measurement of Adsorption Capacity of Unsymmetrical Dimethylhydrazine Gas based on Stainless Steel

Abstract

Unsymmetrical dimethylhydrazine (UDMH), as a high-energy liquid propellant, is widely used in aerospace, rocket, aircraft, and other fields. However, it also has certain toxicity, fire, and explosion risks, which will cause harm to the human liver, kidney, central nervous system, blood system, etc., especially the nervous system. UDMH is easy to be adsorbed on the surface of the human body or other substances, but there is a lack of research reports on the measurement of its adsorption capacity. In this paper, based on the principle of measuring gas adsorption capacity by the volumetric method, a set of UDMH gas adsorption capacity testing devices was built. In the experiment, 304 and 316L stainless steel materials were used as the adsorbent. Under the same experimental temperature and pressure conditions, the test bottle containing the adsorbent was filled with UDMH gas of different concentrations and fully adsorbed until saturation to explore the influence of 304 stainless steel surface roughness and 304 and 316L stainless steel materials on the adsorption capacity of UDMH gas under the same experimental conditions. The experimental results show that the adsorption capacity of 304 and 316L stainless steel materials to UDMH gas increases with the increase of UDMH gas concentration in the concentration range (0~100 ppm) studied in this paper. After polishing the surface of 304 stainless steel material, compared with the unpolished 304 stainless steel material under the same conditions, the adsorption capacity after polishing is significantly smaller, indicating that the larger the surface roughness of the adsorbent, the more adsorption capacity. Under the same conditions, the adsorption capacity of UDMH gas on 304 and 316L stainless steel materials is approximately equal. The experiment also proves that the adsorption of UDMH gas on stainless steel materials conforms to monolayer adsorption within the concentration range studied in this paper.