How fast is the corrosion reaction of HCN-H2S-H2O?

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The reaction rate of this corrosion system is influenced by multiple factors, with no fixed value; it varies significantly under different operating conditions. Characteristics of the basic corrosion rate: Carbon steel exhibits an extremely high initial corrosion rate in this system, reaching over 10 mm/year in the first few days. This rate changes over time as an FeS film is formed, but CN⁻ dissolves this protective film, allowing corrosion to continue at a high pace. The measured corrosion rates for different materials show that the uniform corrosion rate of 08Cr2AlMo steel under the corresponding operating conditions is only 0.2 mg/(cm²·h), which is much lower than that of ordinary carbon steel, indicating superior corrosion resistance. Key influencing factor: An increase in temperature accelerates the reaction rate, with the corrosion rate reaching its peak at around 80°C ； Corrosion increases significantly when the pH value is below 6 ； The higher the concentrations of H₂S and CN⁻, and the faster the medium flow rate, the greater the corrosion rate as well.