The solubility of hydrogen gas in steel in terms of its mass fraction is given as where P...

The solubility of hydrogen gas in steel in terms of its mass fraction is given as where PH2 is the partial pressure of hydrogen in bars and T is the temperature in K. If natural gas is transported in a 1-cm- thick, 3-m-internal-diameter steel pipe at 500 kPa pressure and the mole fraction of hydrogen in the natural gas is 8 percent, determine the highest rate of hydrogen loss through a 100-m- long section of the pipe at steady conditions at a temperature of 293 K if the pipe is exposed to air. Take the diffusivity of hydrogen in steel to be 2.9 × 10–13 m2/s.

Answer: 3.98 × 10–14 kg/s