Question

The purification of hydrogen gas is possible by diffusion through a thin palladium sheet. Calculate the number of kilograms of hydrogen that pass per hour through a thick sheet of palladium having an area and thickness listed above at 500C. Assume a diffusion coefficient of 8.9x10-8 m2/s, that the concentrations at the high- and low-pressure sides of the plates are 3.3 and 0.64 kg/m3 of hydrogen per cubic meter of palladium, and that steady-state conditions have been attained.(Answer in Engineering Notation)

Answer 1

Answer:

m = 0.04955 kg/h

Explanation:

Given data:

Assume Thickness  of sheet = 4.3 mm

              and area of 0.25 m^2

Temperature = 500 degree C

Mass of hydrogen/ hr can be calculated as

$m = \frac{DA(C_1 -C_2)}{L} \times t$

Where,

D - Diffusion constant$= 8.9\times 10^{-8} m^2/s \frac{3600 m^2/h}{1 m^2/s}$

A - Area of sheet = 0.25 m^2

L  - thickness = 4.3 mm = 4.3 \times 10^{-3} m

$C_1$ = Higher preesure side concentration of hydrogen = 3.3 kg/m^3

$C_2$ = low pressure side concentration of hydrogen = 0.64  kg/m^3

t =1 hr

therefore m value is $m = \frac{3.3 - 0.64}{1.3\times ^{-3}} \times 8.9\times 10^{-8}\times 0.25\times 3600 \times 1$

m = 0.04955 kg/h