Designing a Helium Separation Method Using Pyrex Glass

How can we design a method for separating helium from natural gas using pyrex glass?

What is the relationship between the diffusivity of helium through pyrex glass, interfacial concentrations of helium in pyrex, and the dimensions of the tube?

Designing a Helium Separation Method Using Pyrex Glass

To create a method for separating helium from natural gas using pyrex glass, we need to understand the principles of diffusion through pyrex. The diffusivity of helium through pyrex is approximately 25 times higher than that of hydrogen, making helium the gas most likely to permeate through the pyrex material. This indicates that we can leverage the relative diffusion rates through pyrex to separate helium from natural gas.

Pyrex glass is known to be impermeable to most gases, except helium. This unique property makes pyrex an ideal material for separating helium from other gases. By utilizing the diffusivity of helium through pyrex, along with the interfacial concentrations of helium in pyrex and the dimensions of the tube, we can design a system that allows helium to "leak" out of the pyrex tube while trapping other gases.

The rate of helium diffusion through pyrex can be calculated using the following expression:

This formula indicates that the rate at which helium will leak out of the pyrex tube is directly proportional to the diffusivity of helium through pyrex, the concentration of helium at the pyrex interface, and the dimensions of the pyrex tube. By controlling these factors, we can effectively separate helium from natural gas based on their diffusion rates through pyrex.