Process materials (gases and chemicals)

Which material is widely used for piping and containers of highly corrosive chemicals such as hydrofluoric acid?

  1. AFluoropolymers such as PFA
  2. BAluminum
  3. COrdinary glass
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Answer: A. Fluoropolymers such as PFA

Fluoropolymers such as PFA and PTFE resist almost all chemicals, including hydrofluoric acid, and leach very few impurities, so they are widely used for high-purity chemical piping, fittings, containers and valves. Glass dissolves in HF, and aluminum is attacked by acids and alkalis.

  • A. Correct. Fluoropolymers resist chemicals and release few impurities.
  • B. Aluminum is attacked by acids and alkalis.
  • C. Glass dissolves in hydrofluoric acid.
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