Inert gas and fuel gas influence on the pressure limits of stability of acetylene

Chemically unstable gases can decompose in an explosion reaction also in the absence of oxidizing agents. In order to avoid these hazards, the knowledge of the stability limits of such gases is very important. At present, no standard methods exist for the experimental determination of the stability limits of pure gases and mixtures. With a test apparatus developed by BAM the pressure limits of stability were measured for C2H2/N2, C2H2/CO2, C2H2/H2 and C2H2/NH3 gas mixtures at initial temperatures of 20 °C and 100 °C. Lowering the amount of C2H2 in the gas mixture results in a rising pressure limit of stability. The phlegmatizing influence of foreign gases increases in the order H2 > N2 > CO2 > NH3. The pressure limits of stability were also determined for C2H2/C2H4 gas mixtures at initial temperature of 20 °C, 100 °C and 150 °C. The pressure limits increase with removing amount of C2H2 from the pressure limit of pure C2H2 up to the stability limit of pure C2H4.